Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Dongjin Lee]

Hi Ismael,

Sure. Thanks.

- Dongjin

On Wed, Sep 12, 2018 at 11:56 PM Ismael Juma  wrote:

> Dongjin, can you please start a vote?
>
> Ismael
>
> On Sun, Sep 9, 2018 at 11:15 PM Dongjin Lee  wrote:
>
> > Hi Jason,
> >
> > You are right. Explicit statements are always better. I updated the
> > document following your suggestion.
> >
> > @Magnus
> >
> > Thanks for the inspection. It seems like a new error code is not a
> problem.
> >
> > Thanks,
> > Dongjin
> >
> > On Fri, Sep 7, 2018 at 3:23 AM Jason Gustafson 
> wrote:
> >
> > > Hi Dongjin,
> > >
> > > The KIP looks good to me. I'd suggest starting a vote. A couple minor
> > > points that might be worth calling out explicitly in the compatibility
> > > section:
> > >
> > > 1. Zstd will only be allowed for the bumped produce API. For older
> > > versions, we return UNSUPPORTED_COMPRESSION_TYPE regardless of the
> > message
> > > format.
> > > 2. Down-conversion of zstd-compressed records will not be supported.
> > > Instead we will return UNSUPPORTED_COMPRESSION_TYPE.
> > >
> > > Does that sound right?
> > >
> > > Thanks,
> > > Jason
> > >
> > > On Thu, Sep 6, 2018 at 1:45 AM, Magnus Edenhill 
> > > wrote:
> > >
> > > > > Ismael wrote:
> > > > > Jason, that's an interesting point regarding the Java client. Do we
> > > know
> > > > > what clients in other languages do in these cases?
> > > >
> > > > librdkafka (and its bindings) passes unknown/future errors through to
> > the
> > > > application, the error code remains intact while
> > > > the error string will be set to something like "Err-123?", which
> isn't
> > > very
> > > > helpful to the user but it at least
> > > > preserves the original error code for further troubleshooting.
> > > > For the producer any unknown error returned in the ProduceResponse
> will
> > > be
> > > > considered a permanent delivery failure (no retries),
> > > > and for the consumer any unknown FetchResponse errors will propagate
> > > > directly to the application, trigger a fetch backoff, and then
> > > > continue fetching past that offset.
> > > >
> > > > So, from the client's perspective it is not really a problem if new
> > error
> > > > codes are added to older API versions.
> > > >
> > > > /Magnus
> > > >
> > > >
> > > > Den tors 6 sep. 2018 kl 09:45 skrev Dongjin Lee  >:
> > > >
> > > > > I updated the KIP page
> > > > > <
> > > > > https://cwiki.apache.org/confluence/display/KAFKA/KIP-
> > > > 110%3A+Add+Codec+for+ZStandard+Compression
> > > > > >
> > > > > following the discussion here. Please take a look when you are
> free.
> > > > > If you have any opinion, don't hesitate to give me a message.
> > > > >
> > > > > Best,
> > > > > Dongjin
> > > > >
> > > > > On Fri, Aug 31, 2018 at 11:35 PM Dongjin Lee 
> > > wrote:
> > > > >
> > > > > > I just updated the draft implementation[^1], rebasing against the
> > > > latest
> > > > > > trunk and implementing error routine (i.e., Error code 74 for
> > > > > > UnsupportedCompressionTypeException.) Since we decided to
> disallow
> > > all
> > > > > > fetch request below version 2.1.0 for the topics specifying
> > > ZStandard,
> > > > I
> > > > > > added an error logic only.
> > > > > >
> > > > > > Please have a look when you are free.
> > > > > >
> > > > > > Thanks,
> > > > > > Dongjin
> > > > > >
> > > > > > [^1]: Please check the last commit here:
> > > > > > https://github.com/apache/kafka/pull/2267
> > > > > >
> > > > > > On Thu, Aug 23, 2018, 8:55 AM Dongjin Lee 
> > > wrote:
> > > > > >
> > > > > >> Jason,
> > > > > >>
> > > > > >> Great. +1 for UNSUPPORTED_COMPRESSION_TYPE.
> > > > > >>
> > > > > >> Best,
> > > > > >> Dongjin
> > > > > >>
> > > > > >> On Thu, Aug 23, 2018 at 8:19 AM Jason Gustafson <
> > ja...@confluent.io
> > > >
> > > > > >> wrote:
> > > > > >>
> > > > > >>> Hey Dongjin,
> > > > > >>>
> > > > > >>> Yeah that's right. For what it's worth, librdkafka also appears
> > to
> > > > > handle
> > > > > >>> unexpected error codes. I expect that most client
> implementations
> > > > would
> > > > > >>> either pass through the raw type or convert to an enum using
> > > > something
> > > > > >>> like
> > > > > >>> what the java client does. Since we're expecting the client to
> > fail
> > > > > >>> anyway,
> > > > > >>> I'm probably in favor of using the UNSUPPORTED_COMPRESSION_TYPE
> > > error
> > > > > >>> code.
> > > > > >>>
> > > > > >>> -Jason
> > > > > >>>
> > > > > >>> On Wed, Aug 22, 2018 at 1:46 AM, Dongjin Lee <
> dong...@apache.org
> > >
> > > > > wrote:
> > > > > >>>
> > > > > >>> > Jason and Ismael,
> > > > > >>> >
> > > > > >>> > It seems like the only thing we need to regard if we define a
> > new
> > > > > error
> > > > > >>> > code (i.e., UNSUPPORTED_COMPRESSION_TYPE) would be the
> > > > implementation
> > > > > >>> of
> > > > > >>> > the other language clients, right? At least, this strategy
> > causes
> > > > any
> > > > > >>> > problem for Java client. Do I understand correctly?
> > > > > >>> >
> > > > > >>> > Thanks,
> > > > > >>> > 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Ismael Juma]

Dongjin, can you please start a vote?

Ismael

On Sun, Sep 9, 2018 at 11:15 PM Dongjin Lee  wrote:

> Hi Jason,
>
> You are right. Explicit statements are always better. I updated the
> document following your suggestion.
>
> @Magnus
>
> Thanks for the inspection. It seems like a new error code is not a problem.
>
> Thanks,
> Dongjin
>
> On Fri, Sep 7, 2018 at 3:23 AM Jason Gustafson  wrote:
>
> > Hi Dongjin,
> >
> > The KIP looks good to me. I'd suggest starting a vote. A couple minor
> > points that might be worth calling out explicitly in the compatibility
> > section:
> >
> > 1. Zstd will only be allowed for the bumped produce API. For older
> > versions, we return UNSUPPORTED_COMPRESSION_TYPE regardless of the
> message
> > format.
> > 2. Down-conversion of zstd-compressed records will not be supported.
> > Instead we will return UNSUPPORTED_COMPRESSION_TYPE.
> >
> > Does that sound right?
> >
> > Thanks,
> > Jason
> >
> > On Thu, Sep 6, 2018 at 1:45 AM, Magnus Edenhill 
> > wrote:
> >
> > > > Ismael wrote:
> > > > Jason, that's an interesting point regarding the Java client. Do we
> > know
> > > > what clients in other languages do in these cases?
> > >
> > > librdkafka (and its bindings) passes unknown/future errors through to
> the
> > > application, the error code remains intact while
> > > the error string will be set to something like "Err-123?", which isn't
> > very
> > > helpful to the user but it at least
> > > preserves the original error code for further troubleshooting.
> > > For the producer any unknown error returned in the ProduceResponse will
> > be
> > > considered a permanent delivery failure (no retries),
> > > and for the consumer any unknown FetchResponse errors will propagate
> > > directly to the application, trigger a fetch backoff, and then
> > > continue fetching past that offset.
> > >
> > > So, from the client's perspective it is not really a problem if new
> error
> > > codes are added to older API versions.
> > >
> > > /Magnus
> > >
> > >
> > > Den tors 6 sep. 2018 kl 09:45 skrev Dongjin Lee :
> > >
> > > > I updated the KIP page
> > > > <
> > > > https://cwiki.apache.org/confluence/display/KAFKA/KIP-
> > > 110%3A+Add+Codec+for+ZStandard+Compression
> > > > >
> > > > following the discussion here. Please take a look when you are free.
> > > > If you have any opinion, don't hesitate to give me a message.
> > > >
> > > > Best,
> > > > Dongjin
> > > >
> > > > On Fri, Aug 31, 2018 at 11:35 PM Dongjin Lee 
> > wrote:
> > > >
> > > > > I just updated the draft implementation[^1], rebasing against the
> > > latest
> > > > > trunk and implementing error routine (i.e., Error code 74 for
> > > > > UnsupportedCompressionTypeException.) Since we decided to disallow
> > all
> > > > > fetch request below version 2.1.0 for the topics specifying
> > ZStandard,
> > > I
> > > > > added an error logic only.
> > > > >
> > > > > Please have a look when you are free.
> > > > >
> > > > > Thanks,
> > > > > Dongjin
> > > > >
> > > > > [^1]: Please check the last commit here:
> > > > > https://github.com/apache/kafka/pull/2267
> > > > >
> > > > > On Thu, Aug 23, 2018, 8:55 AM Dongjin Lee 
> > wrote:
> > > > >
> > > > >> Jason,
> > > > >>
> > > > >> Great. +1 for UNSUPPORTED_COMPRESSION_TYPE.
> > > > >>
> > > > >> Best,
> > > > >> Dongjin
> > > > >>
> > > > >> On Thu, Aug 23, 2018 at 8:19 AM Jason Gustafson <
> ja...@confluent.io
> > >
> > > > >> wrote:
> > > > >>
> > > > >>> Hey Dongjin,
> > > > >>>
> > > > >>> Yeah that's right. For what it's worth, librdkafka also appears
> to
> > > > handle
> > > > >>> unexpected error codes. I expect that most client implementations
> > > would
> > > > >>> either pass through the raw type or convert to an enum using
> > > something
> > > > >>> like
> > > > >>> what the java client does. Since we're expecting the client to
> fail
> > > > >>> anyway,
> > > > >>> I'm probably in favor of using the UNSUPPORTED_COMPRESSION_TYPE
> > error
> > > > >>> code.
> > > > >>>
> > > > >>> -Jason
> > > > >>>
> > > > >>> On Wed, Aug 22, 2018 at 1:46 AM, Dongjin Lee  >
> > > > wrote:
> > > > >>>
> > > > >>> > Jason and Ismael,
> > > > >>> >
> > > > >>> > It seems like the only thing we need to regard if we define a
> new
> > > > error
> > > > >>> > code (i.e., UNSUPPORTED_COMPRESSION_TYPE) would be the
> > > implementation
> > > > >>> of
> > > > >>> > the other language clients, right? At least, this strategy
> causes
> > > any
> > > > >>> > problem for Java client. Do I understand correctly?
> > > > >>> >
> > > > >>> > Thanks,
> > > > >>> > Dongjin
> > > > >>> >
> > > > >>> > On Wed, Aug 22, 2018 at 5:43 PM Dongjin Lee <
> dong...@apache.org>
> > > > >>> wrote:
> > > > >>> >
> > > > >>> > > Jason,
> > > > >>> > >
> > > > >>> > > > I think we would only use this error code when we /know/
> that
> > > > zstd
> > > > >>> was
> > > > >>> > > in use and the client doesn't support it? This is true if
> > either
> > > 1)
> > > > >>> the
> > > > >>> > > message needs down-conversion 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Dongjin Lee]

Hi Jason,

You are right. Explicit statements are always better. I updated the
document following your suggestion.

@Magnus

Thanks for the inspection. It seems like a new error code is not a problem.

Thanks,
Dongjin

On Fri, Sep 7, 2018 at 3:23 AM Jason Gustafson  wrote:

> Hi Dongjin,
>
> The KIP looks good to me. I'd suggest starting a vote. A couple minor
> points that might be worth calling out explicitly in the compatibility
> section:
>
> 1. Zstd will only be allowed for the bumped produce API. For older
> versions, we return UNSUPPORTED_COMPRESSION_TYPE regardless of the message
> format.
> 2. Down-conversion of zstd-compressed records will not be supported.
> Instead we will return UNSUPPORTED_COMPRESSION_TYPE.
>
> Does that sound right?
>
> Thanks,
> Jason
>
> On Thu, Sep 6, 2018 at 1:45 AM, Magnus Edenhill 
> wrote:
>
> > > Ismael wrote:
> > > Jason, that's an interesting point regarding the Java client. Do we
> know
> > > what clients in other languages do in these cases?
> >
> > librdkafka (and its bindings) passes unknown/future errors through to the
> > application, the error code remains intact while
> > the error string will be set to something like "Err-123?", which isn't
> very
> > helpful to the user but it at least
> > preserves the original error code for further troubleshooting.
> > For the producer any unknown error returned in the ProduceResponse will
> be
> > considered a permanent delivery failure (no retries),
> > and for the consumer any unknown FetchResponse errors will propagate
> > directly to the application, trigger a fetch backoff, and then
> > continue fetching past that offset.
> >
> > So, from the client's perspective it is not really a problem if new error
> > codes are added to older API versions.
> >
> > /Magnus
> >
> >
> > Den tors 6 sep. 2018 kl 09:45 skrev Dongjin Lee :
> >
> > > I updated the KIP page
> > > <
> > > https://cwiki.apache.org/confluence/display/KAFKA/KIP-
> > 110%3A+Add+Codec+for+ZStandard+Compression
> > > >
> > > following the discussion here. Please take a look when you are free.
> > > If you have any opinion, don't hesitate to give me a message.
> > >
> > > Best,
> > > Dongjin
> > >
> > > On Fri, Aug 31, 2018 at 11:35 PM Dongjin Lee 
> wrote:
> > >
> > > > I just updated the draft implementation[^1], rebasing against the
> > latest
> > > > trunk and implementing error routine (i.e., Error code 74 for
> > > > UnsupportedCompressionTypeException.) Since we decided to disallow
> all
> > > > fetch request below version 2.1.0 for the topics specifying
> ZStandard,
> > I
> > > > added an error logic only.
> > > >
> > > > Please have a look when you are free.
> > > >
> > > > Thanks,
> > > > Dongjin
> > > >
> > > > [^1]: Please check the last commit here:
> > > > https://github.com/apache/kafka/pull/2267
> > > >
> > > > On Thu, Aug 23, 2018, 8:55 AM Dongjin Lee 
> wrote:
> > > >
> > > >> Jason,
> > > >>
> > > >> Great. +1 for UNSUPPORTED_COMPRESSION_TYPE.
> > > >>
> > > >> Best,
> > > >> Dongjin
> > > >>
> > > >> On Thu, Aug 23, 2018 at 8:19 AM Jason Gustafson  >
> > > >> wrote:
> > > >>
> > > >>> Hey Dongjin,
> > > >>>
> > > >>> Yeah that's right. For what it's worth, librdkafka also appears to
> > > handle
> > > >>> unexpected error codes. I expect that most client implementations
> > would
> > > >>> either pass through the raw type or convert to an enum using
> > something
> > > >>> like
> > > >>> what the java client does. Since we're expecting the client to fail
> > > >>> anyway,
> > > >>> I'm probably in favor of using the UNSUPPORTED_COMPRESSION_TYPE
> error
> > > >>> code.
> > > >>>
> > > >>> -Jason
> > > >>>
> > > >>> On Wed, Aug 22, 2018 at 1:46 AM, Dongjin Lee 
> > > wrote:
> > > >>>
> > > >>> > Jason and Ismael,
> > > >>> >
> > > >>> > It seems like the only thing we need to regard if we define a new
> > > error
> > > >>> > code (i.e., UNSUPPORTED_COMPRESSION_TYPE) would be the
> > implementation
> > > >>> of
> > > >>> > the other language clients, right? At least, this strategy causes
> > any
> > > >>> > problem for Java client. Do I understand correctly?
> > > >>> >
> > > >>> > Thanks,
> > > >>> > Dongjin
> > > >>> >
> > > >>> > On Wed, Aug 22, 2018 at 5:43 PM Dongjin Lee 
> > > >>> wrote:
> > > >>> >
> > > >>> > > Jason,
> > > >>> > >
> > > >>> > > > I think we would only use this error code when we /know/ that
> > > zstd
> > > >>> was
> > > >>> > > in use and the client doesn't support it? This is true if
> either
> > 1)
> > > >>> the
> > > >>> > > message needs down-conversion and we encounter a zstd
> compressed
> > > >>> message,
> > > >>> > > or 2) if the topic is explicitly configured to use zstd.
> > > >>> > >
> > > >>> > > Yes, it is right. And you know, the case 1 includes 1.a) old
> > > clients'
> > > >>> > > request v0, v1 records or 1.b) implicit zstd, the compression
> > type
> > > of
> > > >>> > > "producer" with Zstd compressed data.
> > > >>> > >
> > > >>> > > > However, if the compression type is set to "producer," 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Jason Gustafson]

Hi Dongjin,

The KIP looks good to me. I'd suggest starting a vote. A couple minor
points that might be worth calling out explicitly in the compatibility
section:

1. Zstd will only be allowed for the bumped produce API. For older
versions, we return UNSUPPORTED_COMPRESSION_TYPE regardless of the message
format.
2. Down-conversion of zstd-compressed records will not be supported.
Instead we will return UNSUPPORTED_COMPRESSION_TYPE.

Does that sound right?

Thanks,
Jason

On Thu, Sep 6, 2018 at 1:45 AM, Magnus Edenhill  wrote:

> > Ismael wrote:
> > Jason, that's an interesting point regarding the Java client. Do we know
> > what clients in other languages do in these cases?
>
> librdkafka (and its bindings) passes unknown/future errors through to the
> application, the error code remains intact while
> the error string will be set to something like "Err-123?", which isn't very
> helpful to the user but it at least
> preserves the original error code for further troubleshooting.
> For the producer any unknown error returned in the ProduceResponse will be
> considered a permanent delivery failure (no retries),
> and for the consumer any unknown FetchResponse errors will propagate
> directly to the application, trigger a fetch backoff, and then
> continue fetching past that offset.
>
> So, from the client's perspective it is not really a problem if new error
> codes are added to older API versions.
>
> /Magnus
>
>
> Den tors 6 sep. 2018 kl 09:45 skrev Dongjin Lee :
>
> > I updated the KIP page
> > <
> > https://cwiki.apache.org/confluence/display/KAFKA/KIP-
> 110%3A+Add+Codec+for+ZStandard+Compression
> > >
> > following the discussion here. Please take a look when you are free.
> > If you have any opinion, don't hesitate to give me a message.
> >
> > Best,
> > Dongjin
> >
> > On Fri, Aug 31, 2018 at 11:35 PM Dongjin Lee  wrote:
> >
> > > I just updated the draft implementation[^1], rebasing against the
> latest
> > > trunk and implementing error routine (i.e., Error code 74 for
> > > UnsupportedCompressionTypeException.) Since we decided to disallow all
> > > fetch request below version 2.1.0 for the topics specifying ZStandard,
> I
> > > added an error logic only.
> > >
> > > Please have a look when you are free.
> > >
> > > Thanks,
> > > Dongjin
> > >
> > > [^1]: Please check the last commit here:
> > > https://github.com/apache/kafka/pull/2267
> > >
> > > On Thu, Aug 23, 2018, 8:55 AM Dongjin Lee  wrote:
> > >
> > >> Jason,
> > >>
> > >> Great. +1 for UNSUPPORTED_COMPRESSION_TYPE.
> > >>
> > >> Best,
> > >> Dongjin
> > >>
> > >> On Thu, Aug 23, 2018 at 8:19 AM Jason Gustafson 
> > >> wrote:
> > >>
> > >>> Hey Dongjin,
> > >>>
> > >>> Yeah that's right. For what it's worth, librdkafka also appears to
> > handle
> > >>> unexpected error codes. I expect that most client implementations
> would
> > >>> either pass through the raw type or convert to an enum using
> something
> > >>> like
> > >>> what the java client does. Since we're expecting the client to fail
> > >>> anyway,
> > >>> I'm probably in favor of using the UNSUPPORTED_COMPRESSION_TYPE error
> > >>> code.
> > >>>
> > >>> -Jason
> > >>>
> > >>> On Wed, Aug 22, 2018 at 1:46 AM, Dongjin Lee 
> > wrote:
> > >>>
> > >>> > Jason and Ismael,
> > >>> >
> > >>> > It seems like the only thing we need to regard if we define a new
> > error
> > >>> > code (i.e., UNSUPPORTED_COMPRESSION_TYPE) would be the
> implementation
> > >>> of
> > >>> > the other language clients, right? At least, this strategy causes
> any
> > >>> > problem for Java client. Do I understand correctly?
> > >>> >
> > >>> > Thanks,
> > >>> > Dongjin
> > >>> >
> > >>> > On Wed, Aug 22, 2018 at 5:43 PM Dongjin Lee 
> > >>> wrote:
> > >>> >
> > >>> > > Jason,
> > >>> > >
> > >>> > > > I think we would only use this error code when we /know/ that
> > zstd
> > >>> was
> > >>> > > in use and the client doesn't support it? This is true if either
> 1)
> > >>> the
> > >>> > > message needs down-conversion and we encounter a zstd compressed
> > >>> message,
> > >>> > > or 2) if the topic is explicitly configured to use zstd.
> > >>> > >
> > >>> > > Yes, it is right. And you know, the case 1 includes 1.a) old
> > clients'
> > >>> > > request v0, v1 records or 1.b) implicit zstd, the compression
> type
> > of
> > >>> > > "producer" with Zstd compressed data.
> > >>> > >
> > >>> > > > However, if the compression type is set to "producer," then the
> > >>> fetched
> > >>> > > data may or may not be compressed with zstd. In this case, we
> > return
> > >>> the
> > >>> > > data to the client and expect it to fail parsing. Is that
> correct?
> > >>> > >
> > >>> > > Exactly.
> > >>> > >
> > >>> > > Following your message, I reviewed the implementation of
> > >>> > > `KafkaApis#handleFetchRequest,` which handles the fetch request.
> > And
> > >>> > found
> > >>> > > that the information we can use is like the following:
> > >>> > >
> > >>> > > 1. Client's fetch request version. (`versionId` variable)
> > >>> 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Magnus Edenhill]

> Ismael wrote:
> Jason, that's an interesting point regarding the Java client. Do we know
> what clients in other languages do in these cases?

librdkafka (and its bindings) passes unknown/future errors through to the
application, the error code remains intact while
the error string will be set to something like "Err-123?", which isn't very
helpful to the user but it at least
preserves the original error code for further troubleshooting.
For the producer any unknown error returned in the ProduceResponse will be
considered a permanent delivery failure (no retries),
and for the consumer any unknown FetchResponse errors will propagate
directly to the application, trigger a fetch backoff, and then
continue fetching past that offset.

So, from the client's perspective it is not really a problem if new error
codes are added to older API versions.

/Magnus


Den tors 6 sep. 2018 kl 09:45 skrev Dongjin Lee :

> I updated the KIP page
> <
> https://cwiki.apache.org/confluence/display/KAFKA/KIP-110%3A+Add+Codec+for+ZStandard+Compression
> >
> following the discussion here. Please take a look when you are free.
> If you have any opinion, don't hesitate to give me a message.
>
> Best,
> Dongjin
>
> On Fri, Aug 31, 2018 at 11:35 PM Dongjin Lee  wrote:
>
> > I just updated the draft implementation[^1], rebasing against the latest
> > trunk and implementing error routine (i.e., Error code 74 for
> > UnsupportedCompressionTypeException.) Since we decided to disallow all
> > fetch request below version 2.1.0 for the topics specifying ZStandard, I
> > added an error logic only.
> >
> > Please have a look when you are free.
> >
> > Thanks,
> > Dongjin
> >
> > [^1]: Please check the last commit here:
> > https://github.com/apache/kafka/pull/2267
> >
> > On Thu, Aug 23, 2018, 8:55 AM Dongjin Lee  wrote:
> >
> >> Jason,
> >>
> >> Great. +1 for UNSUPPORTED_COMPRESSION_TYPE.
> >>
> >> Best,
> >> Dongjin
> >>
> >> On Thu, Aug 23, 2018 at 8:19 AM Jason Gustafson 
> >> wrote:
> >>
> >>> Hey Dongjin,
> >>>
> >>> Yeah that's right. For what it's worth, librdkafka also appears to
> handle
> >>> unexpected error codes. I expect that most client implementations would
> >>> either pass through the raw type or convert to an enum using something
> >>> like
> >>> what the java client does. Since we're expecting the client to fail
> >>> anyway,
> >>> I'm probably in favor of using the UNSUPPORTED_COMPRESSION_TYPE error
> >>> code.
> >>>
> >>> -Jason
> >>>
> >>> On Wed, Aug 22, 2018 at 1:46 AM, Dongjin Lee 
> wrote:
> >>>
> >>> > Jason and Ismael,
> >>> >
> >>> > It seems like the only thing we need to regard if we define a new
> error
> >>> > code (i.e., UNSUPPORTED_COMPRESSION_TYPE) would be the implementation
> >>> of
> >>> > the other language clients, right? At least, this strategy causes any
> >>> > problem for Java client. Do I understand correctly?
> >>> >
> >>> > Thanks,
> >>> > Dongjin
> >>> >
> >>> > On Wed, Aug 22, 2018 at 5:43 PM Dongjin Lee 
> >>> wrote:
> >>> >
> >>> > > Jason,
> >>> > >
> >>> > > > I think we would only use this error code when we /know/ that
> zstd
> >>> was
> >>> > > in use and the client doesn't support it? This is true if either 1)
> >>> the
> >>> > > message needs down-conversion and we encounter a zstd compressed
> >>> message,
> >>> > > or 2) if the topic is explicitly configured to use zstd.
> >>> > >
> >>> > > Yes, it is right. And you know, the case 1 includes 1.a) old
> clients'
> >>> > > request v0, v1 records or 1.b) implicit zstd, the compression type
> of
> >>> > > "producer" with Zstd compressed data.
> >>> > >
> >>> > > > However, if the compression type is set to "producer," then the
> >>> fetched
> >>> > > data may or may not be compressed with zstd. In this case, we
> return
> >>> the
> >>> > > data to the client and expect it to fail parsing. Is that correct?
> >>> > >
> >>> > > Exactly.
> >>> > >
> >>> > > Following your message, I reviewed the implementation of
> >>> > > `KafkaApis#handleFetchRequest,` which handles the fetch request.
> And
> >>> > found
> >>> > > that the information we can use is like the following:
> >>> > >
> >>> > > 1. Client's fetch request version. (`versionId` variable)
> >>> > > 2. Log's compression type. (`logConfig` variable)
> >>> > >
> >>> > > We can't detect the actual compression type of the data, unless we
> >>> > inspect
> >>> > > the `RecordBatch` included in the `Records` instance (i.e.,
> >>> > > `unconvertedRecords` variable.) Since it requires some performance
> >>> issue,
> >>> > > it is not our option - in short, we can't be sure if given chunks
> of
> >>> data
> >>> > > are compressed with zstd or not.
> >>> > >
> >>> > > So, conclusion: we can return an error in the case of 1.a and 2
> >>> easily,
> >>> > > with the information above. In the case 1.b (implicit zstd), we can
> >>> just
> >>> > > return the data by do nothing special and expect it to fail
> parsing.
> >>> > >
> >>> > > Thanks,
> >>> > > Dongjin
> >>> > >
> >>> > > On Wed, Aug 22, 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Dongjin Lee]

I updated the KIP page

following the discussion here. Please take a look when you are free.
If you have any opinion, don't hesitate to give me a message.

Best,
Dongjin

On Fri, Aug 31, 2018 at 11:35 PM Dongjin Lee  wrote:

> I just updated the draft implementation[^1], rebasing against the latest
> trunk and implementing error routine (i.e., Error code 74 for
> UnsupportedCompressionTypeException.) Since we decided to disallow all
> fetch request below version 2.1.0 for the topics specifying ZStandard, I
> added an error logic only.
>
> Please have a look when you are free.
>
> Thanks,
> Dongjin
>
> [^1]: Please check the last commit here:
> https://github.com/apache/kafka/pull/2267
>
> On Thu, Aug 23, 2018, 8:55 AM Dongjin Lee  wrote:
>
>> Jason,
>>
>> Great. +1 for UNSUPPORTED_COMPRESSION_TYPE.
>>
>> Best,
>> Dongjin
>>
>> On Thu, Aug 23, 2018 at 8:19 AM Jason Gustafson 
>> wrote:
>>
>>> Hey Dongjin,
>>>
>>> Yeah that's right. For what it's worth, librdkafka also appears to handle
>>> unexpected error codes. I expect that most client implementations would
>>> either pass through the raw type or convert to an enum using something
>>> like
>>> what the java client does. Since we're expecting the client to fail
>>> anyway,
>>> I'm probably in favor of using the UNSUPPORTED_COMPRESSION_TYPE error
>>> code.
>>>
>>> -Jason
>>>
>>> On Wed, Aug 22, 2018 at 1:46 AM, Dongjin Lee  wrote:
>>>
>>> > Jason and Ismael,
>>> >
>>> > It seems like the only thing we need to regard if we define a new error
>>> > code (i.e., UNSUPPORTED_COMPRESSION_TYPE) would be the implementation
>>> of
>>> > the other language clients, right? At least, this strategy causes any
>>> > problem for Java client. Do I understand correctly?
>>> >
>>> > Thanks,
>>> > Dongjin
>>> >
>>> > On Wed, Aug 22, 2018 at 5:43 PM Dongjin Lee 
>>> wrote:
>>> >
>>> > > Jason,
>>> > >
>>> > > > I think we would only use this error code when we /know/ that zstd
>>> was
>>> > > in use and the client doesn't support it? This is true if either 1)
>>> the
>>> > > message needs down-conversion and we encounter a zstd compressed
>>> message,
>>> > > or 2) if the topic is explicitly configured to use zstd.
>>> > >
>>> > > Yes, it is right. And you know, the case 1 includes 1.a) old clients'
>>> > > request v0, v1 records or 1.b) implicit zstd, the compression type of
>>> > > "producer" with Zstd compressed data.
>>> > >
>>> > > > However, if the compression type is set to "producer," then the
>>> fetched
>>> > > data may or may not be compressed with zstd. In this case, we return
>>> the
>>> > > data to the client and expect it to fail parsing. Is that correct?
>>> > >
>>> > > Exactly.
>>> > >
>>> > > Following your message, I reviewed the implementation of
>>> > > `KafkaApis#handleFetchRequest,` which handles the fetch request. And
>>> > found
>>> > > that the information we can use is like the following:
>>> > >
>>> > > 1. Client's fetch request version. (`versionId` variable)
>>> > > 2. Log's compression type. (`logConfig` variable)
>>> > >
>>> > > We can't detect the actual compression type of the data, unless we
>>> > inspect
>>> > > the `RecordBatch` included in the `Records` instance (i.e.,
>>> > > `unconvertedRecords` variable.) Since it requires some performance
>>> issue,
>>> > > it is not our option - in short, we can't be sure if given chunks of
>>> data
>>> > > are compressed with zstd or not.
>>> > >
>>> > > So, conclusion: we can return an error in the case of 1.a and 2
>>> easily,
>>> > > with the information above. In the case 1.b (implicit zstd), we can
>>> just
>>> > > return the data by do nothing special and expect it to fail parsing.
>>> > >
>>> > > Thanks,
>>> > > Dongjin
>>> > >
>>> > > On Wed, Aug 22, 2018 at 12:02 PM Ismael Juma 
>>> wrote:
>>> > >
>>> > >> Jason, that's an interesting point regarding the Java client. Do we
>>> know
>>> > >> what clients in other languages do in these cases?
>>> > >>
>>> > >> Ismael
>>> > >>
>>> > >> On Tue, 21 Aug 2018, 17:30 Jason Gustafson, 
>>> wrote:
>>> > >>
>>> > >> > Hi Dongjin,
>>> > >> >
>>> > >> > One of the complications is that old versions of the API will not
>>> > >> expect a
>>> > >> > new error code. However, since we expect this to be a fatal error
>>> > anyway
>>> > >> > for old clients, it may still be more useful to return the correct
>>> > error
>>> > >> > code. For example, the Kafka clients use the following code to
>>> convert
>>> > >> the
>>> > >> > error code:
>>> > >> >
>>> > >> > public static Errors forCode(short code) {
>>> > >> > Errors error = codeToError.get(code);
>>> > >> > if (error != null) {
>>> > >> > return error;
>>> > >> > } else {
>>> > >> > log.warn("Unexpected error code: {}.", code);
>>> > >> > return UNKNOWN_SERVER_ERROR;
>>> > >> > }
>>> > >> > }
>>> > >> >
>>> > >> > If we return an 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Dongjin Lee]

I just updated the draft implementation[^1], rebasing against the latest
trunk and implementing error routine (i.e., Error code 74 for
UnsupportedCompressionTypeException.) Since we decided to disallow all
fetch request below version 2.1.0 for the topics specifying ZStandard, I
added an error logic only.

Please have a look when you are free.

Thanks,
Dongjin

[^1]: Please check the last commit here:
https://github.com/apache/kafka/pull/2267

On Thu, Aug 23, 2018, 8:55 AM Dongjin Lee  wrote:

> Jason,
>
> Great. +1 for UNSUPPORTED_COMPRESSION_TYPE.
>
> Best,
> Dongjin
>
> On Thu, Aug 23, 2018 at 8:19 AM Jason Gustafson 
> wrote:
>
>> Hey Dongjin,
>>
>> Yeah that's right. For what it's worth, librdkafka also appears to handle
>> unexpected error codes. I expect that most client implementations would
>> either pass through the raw type or convert to an enum using something
>> like
>> what the java client does. Since we're expecting the client to fail
>> anyway,
>> I'm probably in favor of using the UNSUPPORTED_COMPRESSION_TYPE error
>> code.
>>
>> -Jason
>>
>> On Wed, Aug 22, 2018 at 1:46 AM, Dongjin Lee  wrote:
>>
>> > Jason and Ismael,
>> >
>> > It seems like the only thing we need to regard if we define a new error
>> > code (i.e., UNSUPPORTED_COMPRESSION_TYPE) would be the implementation of
>> > the other language clients, right? At least, this strategy causes any
>> > problem for Java client. Do I understand correctly?
>> >
>> > Thanks,
>> > Dongjin
>> >
>> > On Wed, Aug 22, 2018 at 5:43 PM Dongjin Lee  wrote:
>> >
>> > > Jason,
>> > >
>> > > > I think we would only use this error code when we /know/ that zstd
>> was
>> > > in use and the client doesn't support it? This is true if either 1)
>> the
>> > > message needs down-conversion and we encounter a zstd compressed
>> message,
>> > > or 2) if the topic is explicitly configured to use zstd.
>> > >
>> > > Yes, it is right. And you know, the case 1 includes 1.a) old clients'
>> > > request v0, v1 records or 1.b) implicit zstd, the compression type of
>> > > "producer" with Zstd compressed data.
>> > >
>> > > > However, if the compression type is set to "producer," then the
>> fetched
>> > > data may or may not be compressed with zstd. In this case, we return
>> the
>> > > data to the client and expect it to fail parsing. Is that correct?
>> > >
>> > > Exactly.
>> > >
>> > > Following your message, I reviewed the implementation of
>> > > `KafkaApis#handleFetchRequest,` which handles the fetch request. And
>> > found
>> > > that the information we can use is like the following:
>> > >
>> > > 1. Client's fetch request version. (`versionId` variable)
>> > > 2. Log's compression type. (`logConfig` variable)
>> > >
>> > > We can't detect the actual compression type of the data, unless we
>> > inspect
>> > > the `RecordBatch` included in the `Records` instance (i.e.,
>> > > `unconvertedRecords` variable.) Since it requires some performance
>> issue,
>> > > it is not our option - in short, we can't be sure if given chunks of
>> data
>> > > are compressed with zstd or not.
>> > >
>> > > So, conclusion: we can return an error in the case of 1.a and 2
>> easily,
>> > > with the information above. In the case 1.b (implicit zstd), we can
>> just
>> > > return the data by do nothing special and expect it to fail parsing.
>> > >
>> > > Thanks,
>> > > Dongjin
>> > >
>> > > On Wed, Aug 22, 2018 at 12:02 PM Ismael Juma 
>> wrote:
>> > >
>> > >> Jason, that's an interesting point regarding the Java client. Do we
>> know
>> > >> what clients in other languages do in these cases?
>> > >>
>> > >> Ismael
>> > >>
>> > >> On Tue, 21 Aug 2018, 17:30 Jason Gustafson, 
>> wrote:
>> > >>
>> > >> > Hi Dongjin,
>> > >> >
>> > >> > One of the complications is that old versions of the API will not
>> > >> expect a
>> > >> > new error code. However, since we expect this to be a fatal error
>> > anyway
>> > >> > for old clients, it may still be more useful to return the correct
>> > error
>> > >> > code. For example, the Kafka clients use the following code to
>> convert
>> > >> the
>> > >> > error code:
>> > >> >
>> > >> > public static Errors forCode(short code) {
>> > >> > Errors error = codeToError.get(code);
>> > >> > if (error != null) {
>> > >> > return error;
>> > >> > } else {
>> > >> > log.warn("Unexpected error code: {}.", code);
>> > >> > return UNKNOWN_SERVER_ERROR;
>> > >> > }
>> > >> > }
>> > >> >
>> > >> > If we return an unsupported error code, it will be converted to an
>> > >> UNKNOWN
>> > >> > error, but at least we will get the message in the log with the
>> > correct
>> > >> > code. That seems preferable to returning a misleading error code.
>> So I
>> > >> > wonder if we can use the new UNSUPPORTED_COMPRESSION_TYPE error
>> even
>> > for
>> > >> > older versions.
>> > >> >
>> > >> > Also, one question just to check my understanding. I think we would
>> > only
>> > >> > use this error code 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Dongjin Lee]

Jason,

Great. +1 for UNSUPPORTED_COMPRESSION_TYPE.

Best,
Dongjin

On Thu, Aug 23, 2018 at 8:19 AM Jason Gustafson  wrote:

> Hey Dongjin,
>
> Yeah that's right. For what it's worth, librdkafka also appears to handle
> unexpected error codes. I expect that most client implementations would
> either pass through the raw type or convert to an enum using something like
> what the java client does. Since we're expecting the client to fail anyway,
> I'm probably in favor of using the UNSUPPORTED_COMPRESSION_TYPE error code.
>
> -Jason
>
> On Wed, Aug 22, 2018 at 1:46 AM, Dongjin Lee  wrote:
>
> > Jason and Ismael,
> >
> > It seems like the only thing we need to regard if we define a new error
> > code (i.e., UNSUPPORTED_COMPRESSION_TYPE) would be the implementation of
> > the other language clients, right? At least, this strategy causes any
> > problem for Java client. Do I understand correctly?
> >
> > Thanks,
> > Dongjin
> >
> > On Wed, Aug 22, 2018 at 5:43 PM Dongjin Lee  wrote:
> >
> > > Jason,
> > >
> > > > I think we would only use this error code when we /know/ that zstd
> was
> > > in use and the client doesn't support it? This is true if either 1) the
> > > message needs down-conversion and we encounter a zstd compressed
> message,
> > > or 2) if the topic is explicitly configured to use zstd.
> > >
> > > Yes, it is right. And you know, the case 1 includes 1.a) old clients'
> > > request v0, v1 records or 1.b) implicit zstd, the compression type of
> > > "producer" with Zstd compressed data.
> > >
> > > > However, if the compression type is set to "producer," then the
> fetched
> > > data may or may not be compressed with zstd. In this case, we return
> the
> > > data to the client and expect it to fail parsing. Is that correct?
> > >
> > > Exactly.
> > >
> > > Following your message, I reviewed the implementation of
> > > `KafkaApis#handleFetchRequest,` which handles the fetch request. And
> > found
> > > that the information we can use is like the following:
> > >
> > > 1. Client's fetch request version. (`versionId` variable)
> > > 2. Log's compression type. (`logConfig` variable)
> > >
> > > We can't detect the actual compression type of the data, unless we
> > inspect
> > > the `RecordBatch` included in the `Records` instance (i.e.,
> > > `unconvertedRecords` variable.) Since it requires some performance
> issue,
> > > it is not our option - in short, we can't be sure if given chunks of
> data
> > > are compressed with zstd or not.
> > >
> > > So, conclusion: we can return an error in the case of 1.a and 2 easily,
> > > with the information above. In the case 1.b (implicit zstd), we can
> just
> > > return the data by do nothing special and expect it to fail parsing.
> > >
> > > Thanks,
> > > Dongjin
> > >
> > > On Wed, Aug 22, 2018 at 12:02 PM Ismael Juma 
> wrote:
> > >
> > >> Jason, that's an interesting point regarding the Java client. Do we
> know
> > >> what clients in other languages do in these cases?
> > >>
> > >> Ismael
> > >>
> > >> On Tue, 21 Aug 2018, 17:30 Jason Gustafson, 
> wrote:
> > >>
> > >> > Hi Dongjin,
> > >> >
> > >> > One of the complications is that old versions of the API will not
> > >> expect a
> > >> > new error code. However, since we expect this to be a fatal error
> > anyway
> > >> > for old clients, it may still be more useful to return the correct
> > error
> > >> > code. For example, the Kafka clients use the following code to
> convert
> > >> the
> > >> > error code:
> > >> >
> > >> > public static Errors forCode(short code) {
> > >> > Errors error = codeToError.get(code);
> > >> > if (error != null) {
> > >> > return error;
> > >> > } else {
> > >> > log.warn("Unexpected error code: {}.", code);
> > >> > return UNKNOWN_SERVER_ERROR;
> > >> > }
> > >> > }
> > >> >
> > >> > If we return an unsupported error code, it will be converted to an
> > >> UNKNOWN
> > >> > error, but at least we will get the message in the log with the
> > correct
> > >> > code. That seems preferable to returning a misleading error code.
> So I
> > >> > wonder if we can use the new UNSUPPORTED_COMPRESSION_TYPE error even
> > for
> > >> > older versions.
> > >> >
> > >> > Also, one question just to check my understanding. I think we would
> > only
> > >> > use this error code when we /know/ that zstd was in use and the
> client
> > >> > doesn't support it? This is true if either 1) the message needs
> > >> > down-conversion and we encounter a zstd compressed message, or 2) if
> > the
> > >> > topic is explicitly configured to use zstd. However, if the
> > compression
> > >> > type is set to "producer," then the fetched data may or may not be
> > >> > compressed with zstd. In this case, we return the data to the client
> > and
> > >> > expect it to fail parsing. Is that correct?
> > >> >
> > >> > Thanks,
> > >> > Jason
> > >> >
> > >> >
> > >> >
> > >> > On Tue, Aug 21, 2018 at 9:08 AM, Dongjin Lee 
> > >> wrote:
> 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Jason Gustafson]

Hey Dongjin,

Yeah that's right. For what it's worth, librdkafka also appears to handle
unexpected error codes. I expect that most client implementations would
either pass through the raw type or convert to an enum using something like
what the java client does. Since we're expecting the client to fail anyway,
I'm probably in favor of using the UNSUPPORTED_COMPRESSION_TYPE error code.

-Jason

On Wed, Aug 22, 2018 at 1:46 AM, Dongjin Lee  wrote:

> Jason and Ismael,
>
> It seems like the only thing we need to regard if we define a new error
> code (i.e., UNSUPPORTED_COMPRESSION_TYPE) would be the implementation of
> the other language clients, right? At least, this strategy causes any
> problem for Java client. Do I understand correctly?
>
> Thanks,
> Dongjin
>
> On Wed, Aug 22, 2018 at 5:43 PM Dongjin Lee  wrote:
>
> > Jason,
> >
> > > I think we would only use this error code when we /know/ that zstd was
> > in use and the client doesn't support it? This is true if either 1) the
> > message needs down-conversion and we encounter a zstd compressed message,
> > or 2) if the topic is explicitly configured to use zstd.
> >
> > Yes, it is right. And you know, the case 1 includes 1.a) old clients'
> > request v0, v1 records or 1.b) implicit zstd, the compression type of
> > "producer" with Zstd compressed data.
> >
> > > However, if the compression type is set to "producer," then the fetched
> > data may or may not be compressed with zstd. In this case, we return the
> > data to the client and expect it to fail parsing. Is that correct?
> >
> > Exactly.
> >
> > Following your message, I reviewed the implementation of
> > `KafkaApis#handleFetchRequest,` which handles the fetch request. And
> found
> > that the information we can use is like the following:
> >
> > 1. Client's fetch request version. (`versionId` variable)
> > 2. Log's compression type. (`logConfig` variable)
> >
> > We can't detect the actual compression type of the data, unless we
> inspect
> > the `RecordBatch` included in the `Records` instance (i.e.,
> > `unconvertedRecords` variable.) Since it requires some performance issue,
> > it is not our option - in short, we can't be sure if given chunks of data
> > are compressed with zstd or not.
> >
> > So, conclusion: we can return an error in the case of 1.a and 2 easily,
> > with the information above. In the case 1.b (implicit zstd), we can just
> > return the data by do nothing special and expect it to fail parsing.
> >
> > Thanks,
> > Dongjin
> >
> > On Wed, Aug 22, 2018 at 12:02 PM Ismael Juma  wrote:
> >
> >> Jason, that's an interesting point regarding the Java client. Do we know
> >> what clients in other languages do in these cases?
> >>
> >> Ismael
> >>
> >> On Tue, 21 Aug 2018, 17:30 Jason Gustafson,  wrote:
> >>
> >> > Hi Dongjin,
> >> >
> >> > One of the complications is that old versions of the API will not
> >> expect a
> >> > new error code. However, since we expect this to be a fatal error
> anyway
> >> > for old clients, it may still be more useful to return the correct
> error
> >> > code. For example, the Kafka clients use the following code to convert
> >> the
> >> > error code:
> >> >
> >> > public static Errors forCode(short code) {
> >> > Errors error = codeToError.get(code);
> >> > if (error != null) {
> >> > return error;
> >> > } else {
> >> > log.warn("Unexpected error code: {}.", code);
> >> > return UNKNOWN_SERVER_ERROR;
> >> > }
> >> > }
> >> >
> >> > If we return an unsupported error code, it will be converted to an
> >> UNKNOWN
> >> > error, but at least we will get the message in the log with the
> correct
> >> > code. That seems preferable to returning a misleading error code. So I
> >> > wonder if we can use the new UNSUPPORTED_COMPRESSION_TYPE error even
> for
> >> > older versions.
> >> >
> >> > Also, one question just to check my understanding. I think we would
> only
> >> > use this error code when we /know/ that zstd was in use and the client
> >> > doesn't support it? This is true if either 1) the message needs
> >> > down-conversion and we encounter a zstd compressed message, or 2) if
> the
> >> > topic is explicitly configured to use zstd. However, if the
> compression
> >> > type is set to "producer," then the fetched data may or may not be
> >> > compressed with zstd. In this case, we return the data to the client
> and
> >> > expect it to fail parsing. Is that correct?
> >> >
> >> > Thanks,
> >> > Jason
> >> >
> >> >
> >> >
> >> > On Tue, Aug 21, 2018 at 9:08 AM, Dongjin Lee 
> >> wrote:
> >> >
> >> > > Ismael, Jason and all,
> >> > >
> >> > > I rewrote the backward compatibility strategy & its alternatives
> like
> >> > > following, based on Ismael & Jason's comments. Since it is not
> >> updated to
> >> > > the wiki yet, don't hesitate to give me a message if you have any
> >> opinion
> >> > > on it.
> >> > >
> >> > > ```
> >> > > *Backward Compatibility*
> >> > >
> >> > > 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Dongjin Lee]

Jason and Ismael,

It seems like the only thing we need to regard if we define a new error
code (i.e., UNSUPPORTED_COMPRESSION_TYPE) would be the implementation of
the other language clients, right? At least, this strategy causes any
problem for Java client. Do I understand correctly?

Thanks,
Dongjin

On Wed, Aug 22, 2018 at 5:43 PM Dongjin Lee  wrote:

> Jason,
>
> > I think we would only use this error code when we /know/ that zstd was
> in use and the client doesn't support it? This is true if either 1) the
> message needs down-conversion and we encounter a zstd compressed message,
> or 2) if the topic is explicitly configured to use zstd.
>
> Yes, it is right. And you know, the case 1 includes 1.a) old clients'
> request v0, v1 records or 1.b) implicit zstd, the compression type of
> "producer" with Zstd compressed data.
>
> > However, if the compression type is set to "producer," then the fetched
> data may or may not be compressed with zstd. In this case, we return the
> data to the client and expect it to fail parsing. Is that correct?
>
> Exactly.
>
> Following your message, I reviewed the implementation of
> `KafkaApis#handleFetchRequest,` which handles the fetch request. And found
> that the information we can use is like the following:
>
> 1. Client's fetch request version. (`versionId` variable)
> 2. Log's compression type. (`logConfig` variable)
>
> We can't detect the actual compression type of the data, unless we inspect
> the `RecordBatch` included in the `Records` instance (i.e.,
> `unconvertedRecords` variable.) Since it requires some performance issue,
> it is not our option - in short, we can't be sure if given chunks of data
> are compressed with zstd or not.
>
> So, conclusion: we can return an error in the case of 1.a and 2 easily,
> with the information above. In the case 1.b (implicit zstd), we can just
> return the data by do nothing special and expect it to fail parsing.
>
> Thanks,
> Dongjin
>
> On Wed, Aug 22, 2018 at 12:02 PM Ismael Juma  wrote:
>
>> Jason, that's an interesting point regarding the Java client. Do we know
>> what clients in other languages do in these cases?
>>
>> Ismael
>>
>> On Tue, 21 Aug 2018, 17:30 Jason Gustafson,  wrote:
>>
>> > Hi Dongjin,
>> >
>> > One of the complications is that old versions of the API will not
>> expect a
>> > new error code. However, since we expect this to be a fatal error anyway
>> > for old clients, it may still be more useful to return the correct error
>> > code. For example, the Kafka clients use the following code to convert
>> the
>> > error code:
>> >
>> > public static Errors forCode(short code) {
>> > Errors error = codeToError.get(code);
>> > if (error != null) {
>> > return error;
>> > } else {
>> > log.warn("Unexpected error code: {}.", code);
>> > return UNKNOWN_SERVER_ERROR;
>> > }
>> > }
>> >
>> > If we return an unsupported error code, it will be converted to an
>> UNKNOWN
>> > error, but at least we will get the message in the log with the correct
>> > code. That seems preferable to returning a misleading error code. So I
>> > wonder if we can use the new UNSUPPORTED_COMPRESSION_TYPE error even for
>> > older versions.
>> >
>> > Also, one question just to check my understanding. I think we would only
>> > use this error code when we /know/ that zstd was in use and the client
>> > doesn't support it? This is true if either 1) the message needs
>> > down-conversion and we encounter a zstd compressed message, or 2) if the
>> > topic is explicitly configured to use zstd. However, if the compression
>> > type is set to "producer," then the fetched data may or may not be
>> > compressed with zstd. In this case, we return the data to the client and
>> > expect it to fail parsing. Is that correct?
>> >
>> > Thanks,
>> > Jason
>> >
>> >
>> >
>> > On Tue, Aug 21, 2018 at 9:08 AM, Dongjin Lee 
>> wrote:
>> >
>> > > Ismael, Jason and all,
>> > >
>> > > I rewrote the backward compatibility strategy & its alternatives like
>> > > following, based on Ismael & Jason's comments. Since it is not
>> updated to
>> > > the wiki yet, don't hesitate to give me a message if you have any
>> opinion
>> > > on it.
>> > >
>> > > ```
>> > > *Backward Compatibility*
>> > >
>> > > We need to establish some backward-compatibility strategy for the
>> case an
>> > > old client subscribes a topic using ZStandard implicitly (i.e.,
>> > > 'compression.type' configuration of given topic is 'producer' and the
>> > > producer compressed the records with ZStandard). We have the following
>> > > options for this situation:
>> > >
>> > > *A. Support ZStandard to the old clients which can understand v0, v1
>> > > messages only.*
>> > >
>> > > This strategy necessarily requires the down-conversion of v2 message
>> > > compressed with Zstandard into v0 or v1 messages, which means a
>> > > considerable performance degradation. So we rejected this strategy.
>> > >
>> > > *B. Bump 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Dongjin Lee]

Jason,

> I think we would only use this error code when we /know/ that zstd was in
use and the client doesn't support it? This is true if either 1) the
message needs down-conversion and we encounter a zstd compressed message,
or 2) if the topic is explicitly configured to use zstd.

Yes, it is right. And you know, the case 1 includes 1.a) old clients'
request v0, v1 records or 1.b) implicit zstd, the compression type of
"producer" with Zstd compressed data.

> However, if the compression type is set to "producer," then the fetched
data may or may not be compressed with zstd. In this case, we return the
data to the client and expect it to fail parsing. Is that correct?

Exactly.

Following your message, I reviewed the implementation of
`KafkaApis#handleFetchRequest,` which handles the fetch request. And found
that the information we can use is like the following:

1. Client's fetch request version. (`versionId` variable)
2. Log's compression type. (`logConfig` variable)

We can't detect the actual compression type of the data, unless we inspect
the `RecordBatch` included in the `Records` instance (i.e.,
`unconvertedRecords` variable.) Since it requires some performance issue,
it is not our option - in short, we can't be sure if given chunks of data
are compressed with zstd or not.

So, conclusion: we can return an error in the case of 1.a and 2 easily,
with the information above. In the case 1.b (implicit zstd), we can just
return the data by do nothing special and expect it to fail parsing.

Thanks,
Dongjin

On Wed, Aug 22, 2018 at 12:02 PM Ismael Juma  wrote:

> Jason, that's an interesting point regarding the Java client. Do we know
> what clients in other languages do in these cases?
>
> Ismael
>
> On Tue, 21 Aug 2018, 17:30 Jason Gustafson,  wrote:
>
> > Hi Dongjin,
> >
> > One of the complications is that old versions of the API will not expect
> a
> > new error code. However, since we expect this to be a fatal error anyway
> > for old clients, it may still be more useful to return the correct error
> > code. For example, the Kafka clients use the following code to convert
> the
> > error code:
> >
> > public static Errors forCode(short code) {
> > Errors error = codeToError.get(code);
> > if (error != null) {
> > return error;
> > } else {
> > log.warn("Unexpected error code: {}.", code);
> > return UNKNOWN_SERVER_ERROR;
> > }
> > }
> >
> > If we return an unsupported error code, it will be converted to an
> UNKNOWN
> > error, but at least we will get the message in the log with the correct
> > code. That seems preferable to returning a misleading error code. So I
> > wonder if we can use the new UNSUPPORTED_COMPRESSION_TYPE error even for
> > older versions.
> >
> > Also, one question just to check my understanding. I think we would only
> > use this error code when we /know/ that zstd was in use and the client
> > doesn't support it? This is true if either 1) the message needs
> > down-conversion and we encounter a zstd compressed message, or 2) if the
> > topic is explicitly configured to use zstd. However, if the compression
> > type is set to "producer," then the fetched data may or may not be
> > compressed with zstd. In this case, we return the data to the client and
> > expect it to fail parsing. Is that correct?
> >
> > Thanks,
> > Jason
> >
> >
> >
> > On Tue, Aug 21, 2018 at 9:08 AM, Dongjin Lee  wrote:
> >
> > > Ismael, Jason and all,
> > >
> > > I rewrote the backward compatibility strategy & its alternatives like
> > > following, based on Ismael & Jason's comments. Since it is not updated
> to
> > > the wiki yet, don't hesitate to give me a message if you have any
> opinion
> > > on it.
> > >
> > > ```
> > > *Backward Compatibility*
> > >
> > > We need to establish some backward-compatibility strategy for the case
> an
> > > old client subscribes a topic using ZStandard implicitly (i.e.,
> > > 'compression.type' configuration of given topic is 'producer' and the
> > > producer compressed the records with ZStandard). We have the following
> > > options for this situation:
> > >
> > > *A. Support ZStandard to the old clients which can understand v0, v1
> > > messages only.*
> > >
> > > This strategy necessarily requires the down-conversion of v2 message
> > > compressed with Zstandard into v0 or v1 messages, which means a
> > > considerable performance degradation. So we rejected this strategy.
> > >
> > > *B. Bump the API version and support only v2-available clients*
> > >
> > > With this approach, we can message the old clients that they are old
> and
> > > should be upgraded. However, there are still several options for the
> > Error
> > > code.
> > >
> > > *B.1. INVALID_REQUEST (42)*
> > >
> > > This option gives the client so little information; the user can be
> > > confused about why the client worked correctly in the past suddenly
> > > encounters a problem. So we rejected this strategy.
> > >
> > > 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Ismael Juma]

Jason, that's an interesting point regarding the Java client. Do we know
what clients in other languages do in these cases?

Ismael

On Tue, 21 Aug 2018, 17:30 Jason Gustafson,  wrote:

> Hi Dongjin,
>
> One of the complications is that old versions of the API will not expect a
> new error code. However, since we expect this to be a fatal error anyway
> for old clients, it may still be more useful to return the correct error
> code. For example, the Kafka clients use the following code to convert the
> error code:
>
> public static Errors forCode(short code) {
> Errors error = codeToError.get(code);
> if (error != null) {
> return error;
> } else {
> log.warn("Unexpected error code: {}.", code);
> return UNKNOWN_SERVER_ERROR;
> }
> }
>
> If we return an unsupported error code, it will be converted to an UNKNOWN
> error, but at least we will get the message in the log with the correct
> code. That seems preferable to returning a misleading error code. So I
> wonder if we can use the new UNSUPPORTED_COMPRESSION_TYPE error even for
> older versions.
>
> Also, one question just to check my understanding. I think we would only
> use this error code when we /know/ that zstd was in use and the client
> doesn't support it? This is true if either 1) the message needs
> down-conversion and we encounter a zstd compressed message, or 2) if the
> topic is explicitly configured to use zstd. However, if the compression
> type is set to "producer," then the fetched data may or may not be
> compressed with zstd. In this case, we return the data to the client and
> expect it to fail parsing. Is that correct?
>
> Thanks,
> Jason
>
>
>
> On Tue, Aug 21, 2018 at 9:08 AM, Dongjin Lee  wrote:
>
> > Ismael, Jason and all,
> >
> > I rewrote the backward compatibility strategy & its alternatives like
> > following, based on Ismael & Jason's comments. Since it is not updated to
> > the wiki yet, don't hesitate to give me a message if you have any opinion
> > on it.
> >
> > ```
> > *Backward Compatibility*
> >
> > We need to establish some backward-compatibility strategy for the case an
> > old client subscribes a topic using ZStandard implicitly (i.e.,
> > 'compression.type' configuration of given topic is 'producer' and the
> > producer compressed the records with ZStandard). We have the following
> > options for this situation:
> >
> > *A. Support ZStandard to the old clients which can understand v0, v1
> > messages only.*
> >
> > This strategy necessarily requires the down-conversion of v2 message
> > compressed with Zstandard into v0 or v1 messages, which means a
> > considerable performance degradation. So we rejected this strategy.
> >
> > *B. Bump the API version and support only v2-available clients*
> >
> > With this approach, we can message the old clients that they are old and
> > should be upgraded. However, there are still several options for the
> Error
> > code.
> >
> > *B.1. INVALID_REQUEST (42)*
> >
> > This option gives the client so little information; the user can be
> > confused about why the client worked correctly in the past suddenly
> > encounters a problem. So we rejected this strategy.
> >
> > *B.2. CORRUPT_MESSAGE (2)*
> >
> > This option gives inaccurate information; the user can be surprised and
> > misunderstand that the log files are broken in some way. So we rejected
> > this strategy.
> >
> > *B.3 UNSUPPORTED_FOR_MESSAGE_FORMAT (43)*
> >
> > The advantage of this approach is we don't need to define a new error
> code;
> > we can reuse it and that's all.
> >
> > The disadvantage of this approach is that it is also a little bit vague;
> > This error code is defined as a work for KIP-98[^1] and now returned in
> the
> > transaction error.
> >
> > *B.4. UNSUPPORTED_COMPRESSION_TYPE (new)*
> >
> > The advantage of this approach is that it is clear and provides an exact
> > description. The disadvantage is we need to add a new error code.
> > ```
> >
> > *It seems like what we need to choose is now so clear:
> > UNSUPPORTED_FOR_MESSAGE_FORMAT (B.3) or UNSUPPORTED_COMPRESSION_TYPE
> > (B.4).*
> > The first one doesn't need a new error message but the latter is more
> > explicit. Which one do you prefer? Since all of you have much more
> > experience and knowledge than me, I will follow your decision. The wiki
> > page will be updated following the decision also.
> >
> > Best,
> > Dongjin
> >
> > [^1]: https://issues.apache.org/jira/browse/KAFKA-4990
> >
> > On Sun, Aug 19, 2018 at 4:58 AM Ismael Juma  wrote:
> >
> > > Sounds reasonable to me.
> > >
> > > Ismael
> > >
> > > On Sat, 18 Aug 2018, 12:20 Jason Gustafson, 
> wrote:
> > >
> > > > Hey Ismael,
> > > >
> > > > Your summary looks good to me. I think it might also be a good idea
> to
> > > add
> > > > a new UNSUPPORTED_COMPRESSION_TYPE error code to go along with the
> > > version
> > > > bumps. We won't be able to use it for old api versions since the
> > clients
> > > > 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Jason Gustafson]

Hi Dongjin,

One of the complications is that old versions of the API will not expect a
new error code. However, since we expect this to be a fatal error anyway
for old clients, it may still be more useful to return the correct error
code. For example, the Kafka clients use the following code to convert the
error code:

public static Errors forCode(short code) {
Errors error = codeToError.get(code);
if (error != null) {
return error;
} else {
log.warn("Unexpected error code: {}.", code);
return UNKNOWN_SERVER_ERROR;
}
}

If we return an unsupported error code, it will be converted to an UNKNOWN
error, but at least we will get the message in the log with the correct
code. That seems preferable to returning a misleading error code. So I
wonder if we can use the new UNSUPPORTED_COMPRESSION_TYPE error even for
older versions.

Also, one question just to check my understanding. I think we would only
use this error code when we /know/ that zstd was in use and the client
doesn't support it? This is true if either 1) the message needs
down-conversion and we encounter a zstd compressed message, or 2) if the
topic is explicitly configured to use zstd. However, if the compression
type is set to "producer," then the fetched data may or may not be
compressed with zstd. In this case, we return the data to the client and
expect it to fail parsing. Is that correct?

Thanks,
Jason



On Tue, Aug 21, 2018 at 9:08 AM, Dongjin Lee  wrote:

> Ismael, Jason and all,
>
> I rewrote the backward compatibility strategy & its alternatives like
> following, based on Ismael & Jason's comments. Since it is not updated to
> the wiki yet, don't hesitate to give me a message if you have any opinion
> on it.
>
> ```
> *Backward Compatibility*
>
> We need to establish some backward-compatibility strategy for the case an
> old client subscribes a topic using ZStandard implicitly (i.e.,
> 'compression.type' configuration of given topic is 'producer' and the
> producer compressed the records with ZStandard). We have the following
> options for this situation:
>
> *A. Support ZStandard to the old clients which can understand v0, v1
> messages only.*
>
> This strategy necessarily requires the down-conversion of v2 message
> compressed with Zstandard into v0 or v1 messages, which means a
> considerable performance degradation. So we rejected this strategy.
>
> *B. Bump the API version and support only v2-available clients*
>
> With this approach, we can message the old clients that they are old and
> should be upgraded. However, there are still several options for the Error
> code.
>
> *B.1. INVALID_REQUEST (42)*
>
> This option gives the client so little information; the user can be
> confused about why the client worked correctly in the past suddenly
> encounters a problem. So we rejected this strategy.
>
> *B.2. CORRUPT_MESSAGE (2)*
>
> This option gives inaccurate information; the user can be surprised and
> misunderstand that the log files are broken in some way. So we rejected
> this strategy.
>
> *B.3 UNSUPPORTED_FOR_MESSAGE_FORMAT (43)*
>
> The advantage of this approach is we don't need to define a new error code;
> we can reuse it and that's all.
>
> The disadvantage of this approach is that it is also a little bit vague;
> This error code is defined as a work for KIP-98[^1] and now returned in the
> transaction error.
>
> *B.4. UNSUPPORTED_COMPRESSION_TYPE (new)*
>
> The advantage of this approach is that it is clear and provides an exact
> description. The disadvantage is we need to add a new error code.
> ```
>
> *It seems like what we need to choose is now so clear:
> UNSUPPORTED_FOR_MESSAGE_FORMAT (B.3) or UNSUPPORTED_COMPRESSION_TYPE
> (B.4).*
> The first one doesn't need a new error message but the latter is more
> explicit. Which one do you prefer? Since all of you have much more
> experience and knowledge than me, I will follow your decision. The wiki
> page will be updated following the decision also.
>
> Best,
> Dongjin
>
> [^1]: https://issues.apache.org/jira/browse/KAFKA-4990
>
> On Sun, Aug 19, 2018 at 4:58 AM Ismael Juma  wrote:
>
> > Sounds reasonable to me.
> >
> > Ismael
> >
> > On Sat, 18 Aug 2018, 12:20 Jason Gustafson,  wrote:
> >
> > > Hey Ismael,
> > >
> > > Your summary looks good to me. I think it might also be a good idea to
> > add
> > > a new UNSUPPORTED_COMPRESSION_TYPE error code to go along with the
> > version
> > > bumps. We won't be able to use it for old api versions since the
> clients
> > > will not understand it, but we can use it going forward so that we're
> not
> > > stuck in a similar situation with a new message format and a new codec
> to
> > > support. Another option is to use UNSUPPORTED_FOR_MESSAGE_FORMAT, but
> it
> > is
> > > not as explicit.
> > >
> > > -Jason
> > >
> > > On Fri, Aug 17, 2018 at 5:19 PM, Ismael Juma 
> wrote:
> > >
> > > > Hi Dongjin and Jason,
> > > >
> > > > I would agree. My summary:
> > > >

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Dongjin Lee]

Ismael, Jason and all,

I rewrote the backward compatibility strategy & its alternatives like
following, based on Ismael & Jason's comments. Since it is not updated to
the wiki yet, don't hesitate to give me a message if you have any opinion
on it.

```
*Backward Compatibility*

We need to establish some backward-compatibility strategy for the case an
old client subscribes a topic using ZStandard implicitly (i.e.,
'compression.type' configuration of given topic is 'producer' and the
producer compressed the records with ZStandard). We have the following
options for this situation:

*A. Support ZStandard to the old clients which can understand v0, v1
messages only.*

This strategy necessarily requires the down-conversion of v2 message
compressed with Zstandard into v0 or v1 messages, which means a
considerable performance degradation. So we rejected this strategy.

*B. Bump the API version and support only v2-available clients*

With this approach, we can message the old clients that they are old and
should be upgraded. However, there are still several options for the Error
code.

*B.1. INVALID_REQUEST (42)*

This option gives the client so little information; the user can be
confused about why the client worked correctly in the past suddenly
encounters a problem. So we rejected this strategy.

*B.2. CORRUPT_MESSAGE (2)*

This option gives inaccurate information; the user can be surprised and
misunderstand that the log files are broken in some way. So we rejected
this strategy.

*B.3 UNSUPPORTED_FOR_MESSAGE_FORMAT (43)*

The advantage of this approach is we don't need to define a new error code;
we can reuse it and that's all.

The disadvantage of this approach is that it is also a little bit vague;
This error code is defined as a work for KIP-98[^1] and now returned in the
transaction error.

*B.4. UNSUPPORTED_COMPRESSION_TYPE (new)*

The advantage of this approach is that it is clear and provides an exact
description. The disadvantage is we need to add a new error code.
```

*It seems like what we need to choose is now so clear:
UNSUPPORTED_FOR_MESSAGE_FORMAT (B.3) or UNSUPPORTED_COMPRESSION_TYPE (B.4).*
The first one doesn't need a new error message but the latter is more
explicit. Which one do you prefer? Since all of you have much more
experience and knowledge than me, I will follow your decision. The wiki
page will be updated following the decision also.

Best,
Dongjin

[^1]: https://issues.apache.org/jira/browse/KAFKA-4990

On Sun, Aug 19, 2018 at 4:58 AM Ismael Juma  wrote:

> Sounds reasonable to me.
>
> Ismael
>
> On Sat, 18 Aug 2018, 12:20 Jason Gustafson,  wrote:
>
> > Hey Ismael,
> >
> > Your summary looks good to me. I think it might also be a good idea to
> add
> > a new UNSUPPORTED_COMPRESSION_TYPE error code to go along with the
> version
> > bumps. We won't be able to use it for old api versions since the clients
> > will not understand it, but we can use it going forward so that we're not
> > stuck in a similar situation with a new message format and a new codec to
> > support. Another option is to use UNSUPPORTED_FOR_MESSAGE_FORMAT, but it
> is
> > not as explicit.
> >
> > -Jason
> >
> > On Fri, Aug 17, 2018 at 5:19 PM, Ismael Juma  wrote:
> >
> > > Hi Dongjin and Jason,
> > >
> > > I would agree. My summary:
> > >
> > > 1. Support zstd with message format 2 only.
> > > 2. Bump produce and fetch request versions.
> > > 3. Provide broker errors whenever possible based on the request version
> > and
> > > rely on clients for the cases where the broker can't validate
> efficiently
> > > (example message format 2 consumer that supports the latest fetch
> version
> > > but doesn't support zstd).
> > >
> > > If there's general agreement on this, I suggest we update the KIP to
> > state
> > > the proposal and to move the rejected options to its own section. And
> > then
> > > start a vote!
> > >
> > > Ismael
> > >
> > > On Fri, Aug 17, 2018 at 4:00 PM Jason Gustafson 
> > > wrote:
> > >
> > > > Hi Dongjin,
> > > >
> > > > Yes, that's a good summary. For clients which support v2, the client
> > can
> > > > parse the message format and hopefully raise a useful error message
> > > > indicating the unsupported compression type. For older clients, our
> > > options
> > > > are probably (1) to down-convert to the old format using no
> compression
> > > > type, or (2) to return an error code. I'm leaning toward the latter
> as
> > > the
> > > > simpler solution, but the challenge is finding a good error code. Two
> > > > possibilities might be INVALID_REQUEST or CORRUPT_MESSAGE. The
> downside
> > > is
> > > > that old clients probably won't get a helpful message. However, at
> > least
> > > > the behavior will be consistent in the sense that all clients will
> fail
> > > if
> > > > they do not support zstandard.
> > > >
> > > > What do you think?
> > > >
> > > > Thanks,
> > > > Jason
> > > >
> > > > On Fri, Aug 17, 2018 at 8:08 AM, Dongjin Lee 
> > wrote:
> > > >
> > > > > Thanks Jason, I reviewed 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Ismael Juma]

Sounds reasonable to me.

Ismael

On Sat, 18 Aug 2018, 12:20 Jason Gustafson,  wrote:

> Hey Ismael,
>
> Your summary looks good to me. I think it might also be a good idea to add
> a new UNSUPPORTED_COMPRESSION_TYPE error code to go along with the version
> bumps. We won't be able to use it for old api versions since the clients
> will not understand it, but we can use it going forward so that we're not
> stuck in a similar situation with a new message format and a new codec to
> support. Another option is to use UNSUPPORTED_FOR_MESSAGE_FORMAT, but it is
> not as explicit.
>
> -Jason
>
> On Fri, Aug 17, 2018 at 5:19 PM, Ismael Juma  wrote:
>
> > Hi Dongjin and Jason,
> >
> > I would agree. My summary:
> >
> > 1. Support zstd with message format 2 only.
> > 2. Bump produce and fetch request versions.
> > 3. Provide broker errors whenever possible based on the request version
> and
> > rely on clients for the cases where the broker can't validate efficiently
> > (example message format 2 consumer that supports the latest fetch version
> > but doesn't support zstd).
> >
> > If there's general agreement on this, I suggest we update the KIP to
> state
> > the proposal and to move the rejected options to its own section. And
> then
> > start a vote!
> >
> > Ismael
> >
> > On Fri, Aug 17, 2018 at 4:00 PM Jason Gustafson 
> > wrote:
> >
> > > Hi Dongjin,
> > >
> > > Yes, that's a good summary. For clients which support v2, the client
> can
> > > parse the message format and hopefully raise a useful error message
> > > indicating the unsupported compression type. For older clients, our
> > options
> > > are probably (1) to down-convert to the old format using no compression
> > > type, or (2) to return an error code. I'm leaning toward the latter as
> > the
> > > simpler solution, but the challenge is finding a good error code. Two
> > > possibilities might be INVALID_REQUEST or CORRUPT_MESSAGE. The downside
> > is
> > > that old clients probably won't get a helpful message. However, at
> least
> > > the behavior will be consistent in the sense that all clients will fail
> > if
> > > they do not support zstandard.
> > >
> > > What do you think?
> > >
> > > Thanks,
> > > Jason
> > >
> > > On Fri, Aug 17, 2018 at 8:08 AM, Dongjin Lee 
> wrote:
> > >
> > > > Thanks Jason, I reviewed the down-converting logic following your
> > > > explanation.[^1] You mean the following routines, right?
> > > >
> > > > -
> > > > https://github.com/apache/kafka/blob/trunk/core/src/
> > > > main/scala/kafka/server/KafkaApis.scala#L534
> > > > -
> > > > https://github.com/apache/kafka/blob/trunk/clients/src/
> > > > main/java/org/apache/kafka/common/record/LazyDownConversionRecords.
> > > > java#L165
> > > > -
> > > > https://github.com/apache/kafka/blob/trunk/clients/src/
> > > > main/java/org/apache/kafka/common/record/RecordsUtil.java#L40
> > > >
> > > > It seems like your stance is like following:
> > > >
> > > > 1. In principle, Kafka does not change the compression codec when
> > > > down-converting, since it requires inspecting the fetched data, which
> > is
> > > > expensive.
> > > > 2. However, there are some cases the fetched data is inspected
> anyway.
> > In
> > > > this case, we can provide compression conversion from Zstandard to
> > > > classical ones[^2].
> > > >
> > > > And from what I understand, the cases where the client without
> > ZStandard
> > > > support receives ZStandard compressed records can be organized into
> two
> > > > cases:
> > > >
> > > > a. The 'compression.type' configuration of given topic is 'producer'
> > and
> > > > the producer compressed the records with ZStandard. (that is, using
> > > > ZStandard implicitly.)
> > > > b.  The 'compression.type' configuration of given topic is 'zstd';
> that
> > > is,
> > > > using ZStandard explicitly.
> > > >
> > > > As you stated, we don't have to handle the case b specially. So, It
> > seems
> > > > like we can narrow the focus of the problem by joining case 1 and
> case
> > b
> > > > like the following:
> > > >
> > > > > Given the topic with 'producer' as its 'compression.type'
> > > configuration,
> > > > ZStandard compressed records and old client without ZStandard, is
> there
> > > any
> > > > case we need to inspect the records and can change the compression
> > type?
> > > If
> > > > so, can we provide compression type converting?
> > > >
> > > > Do I understand correctly?
> > > >
> > > > Best,
> > > > Dongjin
> > > >
> > > > [^1]: I'm sorry, I found that I was a little bit misunderstanding how
> > API
> > > > version works, after reviewing the downconvert logic & the protocol
> > > > documentation .
> > > > [^2]: None, Gzip, Snappy, Lz4.
> > > >
> > > > On Tue, Aug 14, 2018 at 2:16 AM Jason Gustafson 
> > > > wrote:
> > > >
> > > > > >
> > > > > > But in my opinion, since the client will fail with the API
> version,
> > > so
> > > > we
> > > > > > don't need to down-convert the messages anyway. Isn't it? So, I
> > 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Jason Gustafson]

Hey Ismael,

Your summary looks good to me. I think it might also be a good idea to add
a new UNSUPPORTED_COMPRESSION_TYPE error code to go along with the version
bumps. We won't be able to use it for old api versions since the clients
will not understand it, but we can use it going forward so that we're not
stuck in a similar situation with a new message format and a new codec to
support. Another option is to use UNSUPPORTED_FOR_MESSAGE_FORMAT, but it is
not as explicit.

-Jason

On Fri, Aug 17, 2018 at 5:19 PM, Ismael Juma  wrote:

> Hi Dongjin and Jason,
>
> I would agree. My summary:
>
> 1. Support zstd with message format 2 only.
> 2. Bump produce and fetch request versions.
> 3. Provide broker errors whenever possible based on the request version and
> rely on clients for the cases where the broker can't validate efficiently
> (example message format 2 consumer that supports the latest fetch version
> but doesn't support zstd).
>
> If there's general agreement on this, I suggest we update the KIP to state
> the proposal and to move the rejected options to its own section. And then
> start a vote!
>
> Ismael
>
> On Fri, Aug 17, 2018 at 4:00 PM Jason Gustafson 
> wrote:
>
> > Hi Dongjin,
> >
> > Yes, that's a good summary. For clients which support v2, the client can
> > parse the message format and hopefully raise a useful error message
> > indicating the unsupported compression type. For older clients, our
> options
> > are probably (1) to down-convert to the old format using no compression
> > type, or (2) to return an error code. I'm leaning toward the latter as
> the
> > simpler solution, but the challenge is finding a good error code. Two
> > possibilities might be INVALID_REQUEST or CORRUPT_MESSAGE. The downside
> is
> > that old clients probably won't get a helpful message. However, at least
> > the behavior will be consistent in the sense that all clients will fail
> if
> > they do not support zstandard.
> >
> > What do you think?
> >
> > Thanks,
> > Jason
> >
> > On Fri, Aug 17, 2018 at 8:08 AM, Dongjin Lee  wrote:
> >
> > > Thanks Jason, I reviewed the down-converting logic following your
> > > explanation.[^1] You mean the following routines, right?
> > >
> > > -
> > > https://github.com/apache/kafka/blob/trunk/core/src/
> > > main/scala/kafka/server/KafkaApis.scala#L534
> > > -
> > > https://github.com/apache/kafka/blob/trunk/clients/src/
> > > main/java/org/apache/kafka/common/record/LazyDownConversionRecords.
> > > java#L165
> > > -
> > > https://github.com/apache/kafka/blob/trunk/clients/src/
> > > main/java/org/apache/kafka/common/record/RecordsUtil.java#L40
> > >
> > > It seems like your stance is like following:
> > >
> > > 1. In principle, Kafka does not change the compression codec when
> > > down-converting, since it requires inspecting the fetched data, which
> is
> > > expensive.
> > > 2. However, there are some cases the fetched data is inspected anyway.
> In
> > > this case, we can provide compression conversion from Zstandard to
> > > classical ones[^2].
> > >
> > > And from what I understand, the cases where the client without
> ZStandard
> > > support receives ZStandard compressed records can be organized into two
> > > cases:
> > >
> > > a. The 'compression.type' configuration of given topic is 'producer'
> and
> > > the producer compressed the records with ZStandard. (that is, using
> > > ZStandard implicitly.)
> > > b.  The 'compression.type' configuration of given topic is 'zstd'; that
> > is,
> > > using ZStandard explicitly.
> > >
> > > As you stated, we don't have to handle the case b specially. So, It
> seems
> > > like we can narrow the focus of the problem by joining case 1 and case
> b
> > > like the following:
> > >
> > > > Given the topic with 'producer' as its 'compression.type'
> > configuration,
> > > ZStandard compressed records and old client without ZStandard, is there
> > any
> > > case we need to inspect the records and can change the compression
> type?
> > If
> > > so, can we provide compression type converting?
> > >
> > > Do I understand correctly?
> > >
> > > Best,
> > > Dongjin
> > >
> > > [^1]: I'm sorry, I found that I was a little bit misunderstanding how
> API
> > > version works, after reviewing the downconvert logic & the protocol
> > > documentation .
> > > [^2]: None, Gzip, Snappy, Lz4.
> > >
> > > On Tue, Aug 14, 2018 at 2:16 AM Jason Gustafson 
> > > wrote:
> > >
> > > > >
> > > > > But in my opinion, since the client will fail with the API version,
> > so
> > > we
> > > > > don't need to down-convert the messages anyway. Isn't it? So, I
> think
> > > we
> > > > > don't care about this case. (I'm sorry, I am not familiar with
> > > > down-convert
> > > > > logic.)
> > > >
> > > >
> > > > Currently the broker down-converts automatically when it receives an
> > old
> > > > version of the fetch request (a version which is known to predate the
> > > > message format in use). Typically when down-converting 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Ismael Juma]

Hi Dongjin and Jason,

I would agree. My summary:

1. Support zstd with message format 2 only.
2. Bump produce and fetch request versions.
3. Provide broker errors whenever possible based on the request version and
rely on clients for the cases where the broker can't validate efficiently
(example message format 2 consumer that supports the latest fetch version
but doesn't support zstd).

If there's general agreement on this, I suggest we update the KIP to state
the proposal and to move the rejected options to its own section. And then
start a vote!

Ismael

On Fri, Aug 17, 2018 at 4:00 PM Jason Gustafson  wrote:

> Hi Dongjin,
>
> Yes, that's a good summary. For clients which support v2, the client can
> parse the message format and hopefully raise a useful error message
> indicating the unsupported compression type. For older clients, our options
> are probably (1) to down-convert to the old format using no compression
> type, or (2) to return an error code. I'm leaning toward the latter as the
> simpler solution, but the challenge is finding a good error code. Two
> possibilities might be INVALID_REQUEST or CORRUPT_MESSAGE. The downside is
> that old clients probably won't get a helpful message. However, at least
> the behavior will be consistent in the sense that all clients will fail if
> they do not support zstandard.
>
> What do you think?
>
> Thanks,
> Jason
>
> On Fri, Aug 17, 2018 at 8:08 AM, Dongjin Lee  wrote:
>
> > Thanks Jason, I reviewed the down-converting logic following your
> > explanation.[^1] You mean the following routines, right?
> >
> > -
> > https://github.com/apache/kafka/blob/trunk/core/src/
> > main/scala/kafka/server/KafkaApis.scala#L534
> > -
> > https://github.com/apache/kafka/blob/trunk/clients/src/
> > main/java/org/apache/kafka/common/record/LazyDownConversionRecords.
> > java#L165
> > -
> > https://github.com/apache/kafka/blob/trunk/clients/src/
> > main/java/org/apache/kafka/common/record/RecordsUtil.java#L40
> >
> > It seems like your stance is like following:
> >
> > 1. In principle, Kafka does not change the compression codec when
> > down-converting, since it requires inspecting the fetched data, which is
> > expensive.
> > 2. However, there are some cases the fetched data is inspected anyway. In
> > this case, we can provide compression conversion from Zstandard to
> > classical ones[^2].
> >
> > And from what I understand, the cases where the client without ZStandard
> > support receives ZStandard compressed records can be organized into two
> > cases:
> >
> > a. The 'compression.type' configuration of given topic is 'producer' and
> > the producer compressed the records with ZStandard. (that is, using
> > ZStandard implicitly.)
> > b.  The 'compression.type' configuration of given topic is 'zstd'; that
> is,
> > using ZStandard explicitly.
> >
> > As you stated, we don't have to handle the case b specially. So, It seems
> > like we can narrow the focus of the problem by joining case 1 and case b
> > like the following:
> >
> > > Given the topic with 'producer' as its 'compression.type'
> configuration,
> > ZStandard compressed records and old client without ZStandard, is there
> any
> > case we need to inspect the records and can change the compression type?
> If
> > so, can we provide compression type converting?
> >
> > Do I understand correctly?
> >
> > Best,
> > Dongjin
> >
> > [^1]: I'm sorry, I found that I was a little bit misunderstanding how API
> > version works, after reviewing the downconvert logic & the protocol
> > documentation .
> > [^2]: None, Gzip, Snappy, Lz4.
> >
> > On Tue, Aug 14, 2018 at 2:16 AM Jason Gustafson 
> > wrote:
> >
> > > >
> > > > But in my opinion, since the client will fail with the API version,
> so
> > we
> > > > don't need to down-convert the messages anyway. Isn't it? So, I think
> > we
> > > > don't care about this case. (I'm sorry, I am not familiar with
> > > down-convert
> > > > logic.)
> > >
> > >
> > > Currently the broker down-converts automatically when it receives an
> old
> > > version of the fetch request (a version which is known to predate the
> > > message format in use). Typically when down-converting the message
> > format,
> > > we use the same compression type, but there is not much point in doing
> so
> > > when we know the client doesn't support it. So if zstandard is in use,
> > and
> > > we have to down-convert anyway, then we can choose to use a different
> > > compression type or no compression type.
> > >
> > > From my perspective, there is no significant downside to bumping the
> > > protocol version and it has several potential benefits. Version bumps
> are
> > > cheap. The main question mark in my mind is about down-conversion.
> > Figuring
> > > out whether down-conversion is needed is hard generally without
> > inspecting
> > > the fetched data, which is expensive. I think we agree in principle
> that
> > we
> > > do not want to have to pay this cost generally 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Jason Gustafson]

Hi Dongjin,

Yes, that's a good summary. For clients which support v2, the client can
parse the message format and hopefully raise a useful error message
indicating the unsupported compression type. For older clients, our options
are probably (1) to down-convert to the old format using no compression
type, or (2) to return an error code. I'm leaning toward the latter as the
simpler solution, but the challenge is finding a good error code. Two
possibilities might be INVALID_REQUEST or CORRUPT_MESSAGE. The downside is
that old clients probably won't get a helpful message. However, at least
the behavior will be consistent in the sense that all clients will fail if
they do not support zstandard.

What do you think?

Thanks,
Jason

On Fri, Aug 17, 2018 at 8:08 AM, Dongjin Lee  wrote:

> Thanks Jason, I reviewed the down-converting logic following your
> explanation.[^1] You mean the following routines, right?
>
> -
> https://github.com/apache/kafka/blob/trunk/core/src/
> main/scala/kafka/server/KafkaApis.scala#L534
> -
> https://github.com/apache/kafka/blob/trunk/clients/src/
> main/java/org/apache/kafka/common/record/LazyDownConversionRecords.
> java#L165
> -
> https://github.com/apache/kafka/blob/trunk/clients/src/
> main/java/org/apache/kafka/common/record/RecordsUtil.java#L40
>
> It seems like your stance is like following:
>
> 1. In principle, Kafka does not change the compression codec when
> down-converting, since it requires inspecting the fetched data, which is
> expensive.
> 2. However, there are some cases the fetched data is inspected anyway. In
> this case, we can provide compression conversion from Zstandard to
> classical ones[^2].
>
> And from what I understand, the cases where the client without ZStandard
> support receives ZStandard compressed records can be organized into two
> cases:
>
> a. The 'compression.type' configuration of given topic is 'producer' and
> the producer compressed the records with ZStandard. (that is, using
> ZStandard implicitly.)
> b.  The 'compression.type' configuration of given topic is 'zstd'; that is,
> using ZStandard explicitly.
>
> As you stated, we don't have to handle the case b specially. So, It seems
> like we can narrow the focus of the problem by joining case 1 and case b
> like the following:
>
> > Given the topic with 'producer' as its 'compression.type' configuration,
> ZStandard compressed records and old client without ZStandard, is there any
> case we need to inspect the records and can change the compression type? If
> so, can we provide compression type converting?
>
> Do I understand correctly?
>
> Best,
> Dongjin
>
> [^1]: I'm sorry, I found that I was a little bit misunderstanding how API
> version works, after reviewing the downconvert logic & the protocol
> documentation .
> [^2]: None, Gzip, Snappy, Lz4.
>
> On Tue, Aug 14, 2018 at 2:16 AM Jason Gustafson 
> wrote:
>
> > >
> > > But in my opinion, since the client will fail with the API version, so
> we
> > > don't need to down-convert the messages anyway. Isn't it? So, I think
> we
> > > don't care about this case. (I'm sorry, I am not familiar with
> > down-convert
> > > logic.)
> >
> >
> > Currently the broker down-converts automatically when it receives an old
> > version of the fetch request (a version which is known to predate the
> > message format in use). Typically when down-converting the message
> format,
> > we use the same compression type, but there is not much point in doing so
> > when we know the client doesn't support it. So if zstandard is in use,
> and
> > we have to down-convert anyway, then we can choose to use a different
> > compression type or no compression type.
> >
> > From my perspective, there is no significant downside to bumping the
> > protocol version and it has several potential benefits. Version bumps are
> > cheap. The main question mark in my mind is about down-conversion.
> Figuring
> > out whether down-conversion is needed is hard generally without
> inspecting
> > the fetched data, which is expensive. I think we agree in principle that
> we
> > do not want to have to pay this cost generally and prefer the clients to
> > fail when they see an unhandled compression type. The point I was making
> is
> > that there are some cases where we are either inspecting the data anyway
> > (because we have to down-convert the message format), or we have an easy
> > way to tell whether zstandard is in use (the topic has it configured
> > explicitly). In the latter case, we don't have to handle it specially.
> But
> > we do have to decide how we will handle down-conversion to older formats.
> >
> > -Jason
> >
> > On Sun, Aug 12, 2018 at 5:15 PM, Dongjin Lee  wrote:
> >
> > > Colin and Jason,
> > >
> > > Thanks for your opinions. In summarizing, the Pros and Cons of bumping
> > > fetch API version are:
> > >
> > > Cons:
> > >
> > > - The Broker can't know whether a given message batch is compressed
> with
> > > zstd or not.
> > > - 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Dongjin Lee]

Thanks Jason, I reviewed the down-converting logic following your
explanation.[^1] You mean the following routines, right?

-
https://github.com/apache/kafka/blob/trunk/core/src/main/scala/kafka/server/KafkaApis.scala#L534
-
https://github.com/apache/kafka/blob/trunk/clients/src/main/java/org/apache/kafka/common/record/LazyDownConversionRecords.java#L165
-
https://github.com/apache/kafka/blob/trunk/clients/src/main/java/org/apache/kafka/common/record/RecordsUtil.java#L40

It seems like your stance is like following:

1. In principle, Kafka does not change the compression codec when
down-converting, since it requires inspecting the fetched data, which is
expensive.
2. However, there are some cases the fetched data is inspected anyway. In
this case, we can provide compression conversion from Zstandard to
classical ones[^2].

And from what I understand, the cases where the client without ZStandard
support receives ZStandard compressed records can be organized into two
cases:

a. The 'compression.type' configuration of given topic is 'producer' and
the producer compressed the records with ZStandard. (that is, using
ZStandard implicitly.)
b.  The 'compression.type' configuration of given topic is 'zstd'; that is,
using ZStandard explicitly.

As you stated, we don't have to handle the case b specially. So, It seems
like we can narrow the focus of the problem by joining case 1 and case b
like the following:

> Given the topic with 'producer' as its 'compression.type' configuration,
ZStandard compressed records and old client without ZStandard, is there any
case we need to inspect the records and can change the compression type? If
so, can we provide compression type converting?

Do I understand correctly?

Best,
Dongjin

[^1]: I'm sorry, I found that I was a little bit misunderstanding how API
version works, after reviewing the downconvert logic & the protocol
documentation .
[^2]: None, Gzip, Snappy, Lz4.

On Tue, Aug 14, 2018 at 2:16 AM Jason Gustafson  wrote:

> >
> > But in my opinion, since the client will fail with the API version, so we
> > don't need to down-convert the messages anyway. Isn't it? So, I think we
> > don't care about this case. (I'm sorry, I am not familiar with
> down-convert
> > logic.)
>
>
> Currently the broker down-converts automatically when it receives an old
> version of the fetch request (a version which is known to predate the
> message format in use). Typically when down-converting the message format,
> we use the same compression type, but there is not much point in doing so
> when we know the client doesn't support it. So if zstandard is in use, and
> we have to down-convert anyway, then we can choose to use a different
> compression type or no compression type.
>
> From my perspective, there is no significant downside to bumping the
> protocol version and it has several potential benefits. Version bumps are
> cheap. The main question mark in my mind is about down-conversion. Figuring
> out whether down-conversion is needed is hard generally without inspecting
> the fetched data, which is expensive. I think we agree in principle that we
> do not want to have to pay this cost generally and prefer the clients to
> fail when they see an unhandled compression type. The point I was making is
> that there are some cases where we are either inspecting the data anyway
> (because we have to down-convert the message format), or we have an easy
> way to tell whether zstandard is in use (the topic has it configured
> explicitly). In the latter case, we don't have to handle it specially. But
> we do have to decide how we will handle down-conversion to older formats.
>
> -Jason
>
> On Sun, Aug 12, 2018 at 5:15 PM, Dongjin Lee  wrote:
>
> > Colin and Jason,
> >
> > Thanks for your opinions. In summarizing, the Pros and Cons of bumping
> > fetch API version are:
> >
> > Cons:
> >
> > - The Broker can't know whether a given message batch is compressed with
> > zstd or not.
> > - Need some additional logic for the topic explicitly configured to use
> > zstd.
> >
> > Pros:
> >
> > - The broker doesn't need to conduct expensive down-conversion.
> > - Can message the users to update their client.
> >
> > So, opinions for the backward-compatibility policy by far:
> >
> > - A: bump the API version - +2 (Colin, Jason)
> > - B: leave unchanged - +1 (Viktor)
> >
> > Here are my additional comments:
> >
> > @Colin
> >
> > I greatly appreciate your response. In the case of the dictionary
> support,
> > of course, this issue should be addressed later so we don't need it in
> the
> > first version. You are right - it is not late to try it after some
> > benchmarks. What I mean is, we should keep in mind on that potential
> > feature.
> >
> > @Jason
> >
> > You wrote,
> >
> > > Similarly, if we have to down-convert anyway because the client does
> not
> > understand the message format, then we could also use a different
> > compression type.
> >
> > But in my opinion, 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Jason Gustafson]

>
> But in my opinion, since the client will fail with the API version, so we
> don't need to down-convert the messages anyway. Isn't it? So, I think we
> don't care about this case. (I'm sorry, I am not familiar with down-convert
> logic.)


Currently the broker down-converts automatically when it receives an old
version of the fetch request (a version which is known to predate the
message format in use). Typically when down-converting the message format,
we use the same compression type, but there is not much point in doing so
when we know the client doesn't support it. So if zstandard is in use, and
we have to down-convert anyway, then we can choose to use a different
compression type or no compression type.

>From my perspective, there is no significant downside to bumping the
protocol version and it has several potential benefits. Version bumps are
cheap. The main question mark in my mind is about down-conversion. Figuring
out whether down-conversion is needed is hard generally without inspecting
the fetched data, which is expensive. I think we agree in principle that we
do not want to have to pay this cost generally and prefer the clients to
fail when they see an unhandled compression type. The point I was making is
that there are some cases where we are either inspecting the data anyway
(because we have to down-convert the message format), or we have an easy
way to tell whether zstandard is in use (the topic has it configured
explicitly). In the latter case, we don't have to handle it specially. But
we do have to decide how we will handle down-conversion to older formats.

-Jason

On Sun, Aug 12, 2018 at 5:15 PM, Dongjin Lee  wrote:

> Colin and Jason,
>
> Thanks for your opinions. In summarizing, the Pros and Cons of bumping
> fetch API version are:
>
> Cons:
>
> - The Broker can't know whether a given message batch is compressed with
> zstd or not.
> - Need some additional logic for the topic explicitly configured to use
> zstd.
>
> Pros:
>
> - The broker doesn't need to conduct expensive down-conversion.
> - Can message the users to update their client.
>
> So, opinions for the backward-compatibility policy by far:
>
> - A: bump the API version - +2 (Colin, Jason)
> - B: leave unchanged - +1 (Viktor)
>
> Here are my additional comments:
>
> @Colin
>
> I greatly appreciate your response. In the case of the dictionary support,
> of course, this issue should be addressed later so we don't need it in the
> first version. You are right - it is not late to try it after some
> benchmarks. What I mean is, we should keep in mind on that potential
> feature.
>
> @Jason
>
> You wrote,
>
> > Similarly, if we have to down-convert anyway because the client does not
> understand the message format, then we could also use a different
> compression type.
>
> But in my opinion, since the client will fail with the API version, so we
> don't need to down-convert the messages anyway. Isn't it? So, I think we
> don't care about this case. (I'm sorry, I am not familiar with down-convert
> logic.)
>
> Please give more opinions. Thanks!
>
> - Dongjin
>
>
> On Wed, Aug 8, 2018 at 6:41 AM Jason Gustafson  wrote:
>
> > Hey Colin,
> >
> > The problem for the fetch API is that the broker does not generally know
> if
> > a batch was compressed with zstd unless it parses it. I think the goal
> here
> > is to avoid the expensive down-conversion that is needed to ensure
> > compatibility because it is only necessary if zstd is actually in use.
> But
> > as long as old clients can parse the message format, they should get a
> > reasonable error if they see an unsupported compression type in the
> > attributes. Basically the onus is on users to ensure that their consumers
> > have been updated prior to using zstd. It seems like a reasonable
> tradeoff
> > to me. There are a couple cases that might be worth thinking through:
> >
> > 1. If a topic is explicitly configured to use zstd, then we don't need to
> > check the fetched data for the compression type to know if we need
> > down-conversion. If we did bump the Fetch API version, then we could
> handle
> > this case by either down-converting using a different compression type or
> > returning an error.
> > 2. Similarly, if we have to down-convert anyway because the client does
> not
> > understand the message format, then we could also use a different
> > compression type.
> >
> > For the produce API, I think it's reasonable to bump the api version.
> This
> > can be used by clients to check whether a broker supports zstd. For
> > example, we might support a list of preferred compression types in the
> > producer and we could use the broker to detect which version to use.
> >
> > -Jason
> >
> > On Tue, Aug 7, 2018 at 1:32 PM, Colin McCabe  wrote:
> >
> > > Thanks for bumping this, Dongjin.  ZStd is a good compression codec
> and I
> > > hope we can get this support in soon!
> > >
> > > I would say we can just bump the API version to indicate that ZStd
> > support
> > > is 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Dongjin Lee]

Colin and Jason,

Thanks for your opinions. In summarizing, the Pros and Cons of bumping
fetch API version are:

Cons:

- The Broker can't know whether a given message batch is compressed with
zstd or not.
- Need some additional logic for the topic explicitly configured to use
zstd.

Pros:

- The broker doesn't need to conduct expensive down-conversion.
- Can message the users to update their client.

So, opinions for the backward-compatibility policy by far:

- A: bump the API version - +2 (Colin, Jason)
- B: leave unchanged - +1 (Viktor)

Here are my additional comments:

@Colin

I greatly appreciate your response. In the case of the dictionary support,
of course, this issue should be addressed later so we don't need it in the
first version. You are right - it is not late to try it after some
benchmarks. What I mean is, we should keep in mind on that potential
feature.

@Jason

You wrote,

> Similarly, if we have to down-convert anyway because the client does not
understand the message format, then we could also use a different
compression type.

But in my opinion, since the client will fail with the API version, so we
don't need to down-convert the messages anyway. Isn't it? So, I think we
don't care about this case. (I'm sorry, I am not familiar with down-convert
logic.)

Please give more opinions. Thanks!

- Dongjin


On Wed, Aug 8, 2018 at 6:41 AM Jason Gustafson  wrote:

> Hey Colin,
>
> The problem for the fetch API is that the broker does not generally know if
> a batch was compressed with zstd unless it parses it. I think the goal here
> is to avoid the expensive down-conversion that is needed to ensure
> compatibility because it is only necessary if zstd is actually in use. But
> as long as old clients can parse the message format, they should get a
> reasonable error if they see an unsupported compression type in the
> attributes. Basically the onus is on users to ensure that their consumers
> have been updated prior to using zstd. It seems like a reasonable tradeoff
> to me. There are a couple cases that might be worth thinking through:
>
> 1. If a topic is explicitly configured to use zstd, then we don't need to
> check the fetched data for the compression type to know if we need
> down-conversion. If we did bump the Fetch API version, then we could handle
> this case by either down-converting using a different compression type or
> returning an error.
> 2. Similarly, if we have to down-convert anyway because the client does not
> understand the message format, then we could also use a different
> compression type.
>
> For the produce API, I think it's reasonable to bump the api version. This
> can be used by clients to check whether a broker supports zstd. For
> example, we might support a list of preferred compression types in the
> producer and we could use the broker to detect which version to use.
>
> -Jason
>
> On Tue, Aug 7, 2018 at 1:32 PM, Colin McCabe  wrote:
>
> > Thanks for bumping this, Dongjin.  ZStd is a good compression codec and I
> > hope we can get this support in soon!
> >
> > I would say we can just bump the API version to indicate that ZStd
> support
> > is expected in new clients.  We probably need some way of indicating to
> the
> > older clients that they can't consume the partitions, as well.  Perhaps
> we
> > can use the UNSUPPORTED_FOR_MESSAGE_FORMAT error?
> >
> > The license thing seems straightforward -- it's just a matter of adding
> > the text to the right files as per ASF guidelines.
> >
> > With regard to the dictionary support, do we really need that in the
> first
> > version?  Hopefully message batches are big enough that this isn't
> needed.
> > Some benchmarks might help here.
> >
> > best,
> > Colin
> >
> >
> > On Tue, Aug 7, 2018, at 08:02, Dongjin Lee wrote:
> > > As Kafka 2.0.0 was released, let's reboot this issue, KIP-110
> > >  > 110%3A+Add+Codec+for+ZStandard+Compression>
> > > .
> > >
> > > For newcomers, Here is some summary of the history: KIP-110 was
> > originally
> > > worked for the issue KAFKA-4514 but, it lacked benchmark results to get
> > the
> > > agreement of the community. Later, Ivan Babrou and some other users who
> > > adopted the patch provided their excellent performance report which is
> > now
> > > included in the KIP, but it postponed again because of the community
> was
> > > busy for 2.0.0 release. It is why I now reboot this issue.
> > >
> > > The following is the current status of the feature: You can check the
> > > current draft implementation here
> > > . It is based on zstd 1.3.5
> > and
> > > periodically rebased onto the latest trunk[^1].
> > >
> > > The issues that should be addressed is like following:
> > >
> > > *1. Backward Compatibility*
> > >
> > > To support old consumers, we need to take a strategy to handle the old
> > > consumers. Current candidates are:
> > >
> > > - Bump API version
> > > - Leave 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Jason Gustafson]

Hey Colin,

The problem for the fetch API is that the broker does not generally know if
a batch was compressed with zstd unless it parses it. I think the goal here
is to avoid the expensive down-conversion that is needed to ensure
compatibility because it is only necessary if zstd is actually in use. But
as long as old clients can parse the message format, they should get a
reasonable error if they see an unsupported compression type in the
attributes. Basically the onus is on users to ensure that their consumers
have been updated prior to using zstd. It seems like a reasonable tradeoff
to me. There are a couple cases that might be worth thinking through:

1. If a topic is explicitly configured to use zstd, then we don't need to
check the fetched data for the compression type to know if we need
down-conversion. If we did bump the Fetch API version, then we could handle
this case by either down-converting using a different compression type or
returning an error.
2. Similarly, if we have to down-convert anyway because the client does not
understand the message format, then we could also use a different
compression type.

For the produce API, I think it's reasonable to bump the api version. This
can be used by clients to check whether a broker supports zstd. For
example, we might support a list of preferred compression types in the
producer and we could use the broker to detect which version to use.

-Jason

On Tue, Aug 7, 2018 at 1:32 PM, Colin McCabe  wrote:

> Thanks for bumping this, Dongjin.  ZStd is a good compression codec and I
> hope we can get this support in soon!
>
> I would say we can just bump the API version to indicate that ZStd support
> is expected in new clients.  We probably need some way of indicating to the
> older clients that they can't consume the partitions, as well.  Perhaps we
> can use the UNSUPPORTED_FOR_MESSAGE_FORMAT error?
>
> The license thing seems straightforward -- it's just a matter of adding
> the text to the right files as per ASF guidelines.
>
> With regard to the dictionary support, do we really need that in the first
> version?  Hopefully message batches are big enough that this isn't needed.
> Some benchmarks might help here.
>
> best,
> Colin
>
>
> On Tue, Aug 7, 2018, at 08:02, Dongjin Lee wrote:
> > As Kafka 2.0.0 was released, let's reboot this issue, KIP-110
> >  110%3A+Add+Codec+for+ZStandard+Compression>
> > .
> >
> > For newcomers, Here is some summary of the history: KIP-110 was
> originally
> > worked for the issue KAFKA-4514 but, it lacked benchmark results to get
> the
> > agreement of the community. Later, Ivan Babrou and some other users who
> > adopted the patch provided their excellent performance report which is
> now
> > included in the KIP, but it postponed again because of the community was
> > busy for 2.0.0 release. It is why I now reboot this issue.
> >
> > The following is the current status of the feature: You can check the
> > current draft implementation here
> > . It is based on zstd 1.3.5
> and
> > periodically rebased onto the latest trunk[^1].
> >
> > The issues that should be addressed is like following:
> >
> > *1. Backward Compatibility*
> >
> > To support old consumers, we need to take a strategy to handle the old
> > consumers. Current candidates are:
> >
> > - Bump API version
> > - Leave unchanged: let the old clients fail.
> > - Improve the error messages:
> >
> > *2. Dictionary Support*
> >
> > To support zstd's dictionary feature in the future (if needed), we need
> to
> > sketch how it should be and leave some room for it. As of now, there has
> > been no discussion on this topic yet.
> >
> > *3. License*
> >
> > To use this feature, we need to add license of zstd and zstd-jni to the
> > project. (Thanks to Viktor Somogyi for raising this issue!) It seems like
> > what Apache Spark did would be a good example but there has been no
> > discussion yet.
> >
> > You can find the details of the above issues in the KIP document. Please
> > have a look when you are free, and give me feedback. All kinds of
> > participating are welcome.
> >
> > Best,
> > Dongjin
> >
> > [^1]: At the time of writing, commit 6b4fb8152.
> >
> > On Sat, Jul 14, 2018 at 10:45 PM Dongjin Lee  wrote:
> >
> > > Sorry for the late reply.
> > >
> > > In short, I could not submit the updated KIP by the feature freeze
> > > deadline of 2.0.0. For this reason, it will not be included in the
> 2.0.0
> > > release and all discussion for this issue were postponed after the
> release
> > > of 2.0.0.
> > >
> > > I have been updating the PR following recent updates. Just now, I
> rebased
> > > it against the latest trunk and updated the zstd version into 1.3.5.
> If you
> > > need some request, don't hesitate to notify me. (But not this thread -
> just
> > > send me the message directly.)
> > >
> > > Best,
> > > Dongjin
> > >
> > > On Tue, Jul 10, 2018 at 11:57 PM 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Colin McCabe]

Thanks for bumping this, Dongjin.  ZStd is a good compression codec and I hope 
we can get this support in soon!

I would say we can just bump the API version to indicate that ZStd support is 
expected in new clients.  We probably need some way of indicating to the older 
clients that they can't consume the partitions, as well.  Perhaps we can use 
the UNSUPPORTED_FOR_MESSAGE_FORMAT error?

The license thing seems straightforward -- it's just a matter of adding the 
text to the right files as per ASF guidelines.

With regard to the dictionary support, do we really need that in the first 
version?  Hopefully message batches are big enough that this isn't needed.  
Some benchmarks might help here.

best,
Colin


On Tue, Aug 7, 2018, at 08:02, Dongjin Lee wrote:
> As Kafka 2.0.0 was released, let's reboot this issue, KIP-110
> 
> .
> 
> For newcomers, Here is some summary of the history: KIP-110 was originally
> worked for the issue KAFKA-4514 but, it lacked benchmark results to get the
> agreement of the community. Later, Ivan Babrou and some other users who
> adopted the patch provided their excellent performance report which is now
> included in the KIP, but it postponed again because of the community was
> busy for 2.0.0 release. It is why I now reboot this issue.
> 
> The following is the current status of the feature: You can check the
> current draft implementation here
> . It is based on zstd 1.3.5 and
> periodically rebased onto the latest trunk[^1].
> 
> The issues that should be addressed is like following:
> 
> *1. Backward Compatibility*
> 
> To support old consumers, we need to take a strategy to handle the old
> consumers. Current candidates are:
> 
> - Bump API version
> - Leave unchanged: let the old clients fail.
> - Improve the error messages:
> 
> *2. Dictionary Support*
> 
> To support zstd's dictionary feature in the future (if needed), we need to
> sketch how it should be and leave some room for it. As of now, there has
> been no discussion on this topic yet.
> 
> *3. License*
> 
> To use this feature, we need to add license of zstd and zstd-jni to the
> project. (Thanks to Viktor Somogyi for raising this issue!) It seems like
> what Apache Spark did would be a good example but there has been no
> discussion yet.
> 
> You can find the details of the above issues in the KIP document. Please
> have a look when you are free, and give me feedback. All kinds of
> participating are welcome.
> 
> Best,
> Dongjin
> 
> [^1]: At the time of writing, commit 6b4fb8152.
> 
> On Sat, Jul 14, 2018 at 10:45 PM Dongjin Lee  wrote:
> 
> > Sorry for the late reply.
> >
> > In short, I could not submit the updated KIP by the feature freeze
> > deadline of 2.0.0. For this reason, it will not be included in the 2.0.0
> > release and all discussion for this issue were postponed after the release
> > of 2.0.0.
> >
> > I have been updating the PR following recent updates. Just now, I rebased
> > it against the latest trunk and updated the zstd version into 1.3.5. If you
> > need some request, don't hesitate to notify me. (But not this thread - just
> > send me the message directly.)
> >
> > Best,
> > Dongjin
> >
> > On Tue, Jul 10, 2018 at 11:57 PM Bobby Evans  wrote:
> >
> >> I there any update on this.  The performance improvements are quite
> >> impressive and I really would like to stop forking kafka just to get this
> >> in.
> >>
> >> Thanks,
> >>
> >> Bobby
> >>
> >> On Wed, Jun 13, 2018 at 8:56 PM Dongjin Lee  wrote:
> >>
> >> > Ismael,
> >> >
> >> > Oh, I forgot all of you are on working frenzy for 2.0! No problem, take
> >> > your time. I am also working at another issue now. Thank you for
> >> letting me
> >> > know.
> >> >
> >> > Best,
> >> > Dongjin
> >> >
> >> > On Wed, Jun 13, 2018, 11:44 PM Ismael Juma  wrote:
> >> >
> >> > > Sorry for the delay Dongjin. Everyone is busy finalising 2.0.0. This
> >> KIP
> >> > > seems like a great candidate for 2.1.0 and hopefully there will be
> >> more
> >> > of
> >> > > a discussion next week. :)
> >> > >
> >> > > Ismael
> >> > >
> >> > > On Wed, 13 Jun 2018, 05:17 Dongjin Lee,  wrote:
> >> > >
> >> > > > Hello. I just updated my draft implementation:
> >> > > >
> >> > > > 1. Rebased to latest trunk (commit 5145d6b)
> >> > > > 2. Apply ZStd 1.3.4
> >> > > >
> >> > > > You can check out the implementation from here
> >> > > > . If you experience any
> >> > > problem
> >> > > > running it, don't hesitate to give me a mention.
> >> > > >
> >> > > > Best,
> >> > > > Dongjin
> >> > > >
> >> > > > On Tue, Jun 12, 2018 at 6:50 PM Dongjin Lee 
> >> > wrote:
> >> > > >
> >> > > > > Here is the short conclusion about the license problem: *We can
> >> use
> >> > > zstd
> >> > > > > and zstd-jni without any problem, but we need to include their
> >> > license,
> >> > > > > e.g., BSD 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Dongjin Lee]

As Kafka 2.0.0 was released, let's reboot this issue, KIP-110

.

For newcomers, Here is some summary of the history: KIP-110 was originally
worked for the issue KAFKA-4514 but, it lacked benchmark results to get the
agreement of the community. Later, Ivan Babrou and some other users who
adopted the patch provided their excellent performance report which is now
included in the KIP, but it postponed again because of the community was
busy for 2.0.0 release. It is why I now reboot this issue.

The following is the current status of the feature: You can check the
current draft implementation here
. It is based on zstd 1.3.5 and
periodically rebased onto the latest trunk[^1].

The issues that should be addressed is like following:

*1. Backward Compatibility*

To support old consumers, we need to take a strategy to handle the old
consumers. Current candidates are:

- Bump API version
- Leave unchanged: let the old clients fail.
- Improve the error messages:

*2. Dictionary Support*

To support zstd's dictionary feature in the future (if needed), we need to
sketch how it should be and leave some room for it. As of now, there has
been no discussion on this topic yet.

*3. License*

To use this feature, we need to add license of zstd and zstd-jni to the
project. (Thanks to Viktor Somogyi for raising this issue!) It seems like
what Apache Spark did would be a good example but there has been no
discussion yet.

You can find the details of the above issues in the KIP document. Please
have a look when you are free, and give me feedback. All kinds of
participating are welcome.

Best,
Dongjin

[^1]: At the time of writing, commit 6b4fb8152.

On Sat, Jul 14, 2018 at 10:45 PM Dongjin Lee  wrote:

> Sorry for the late reply.
>
> In short, I could not submit the updated KIP by the feature freeze
> deadline of 2.0.0. For this reason, it will not be included in the 2.0.0
> release and all discussion for this issue were postponed after the release
> of 2.0.0.
>
> I have been updating the PR following recent updates. Just now, I rebased
> it against the latest trunk and updated the zstd version into 1.3.5. If you
> need some request, don't hesitate to notify me. (But not this thread - just
> send me the message directly.)
>
> Best,
> Dongjin
>
> On Tue, Jul 10, 2018 at 11:57 PM Bobby Evans  wrote:
>
>> I there any update on this.  The performance improvements are quite
>> impressive and I really would like to stop forking kafka just to get this
>> in.
>>
>> Thanks,
>>
>> Bobby
>>
>> On Wed, Jun 13, 2018 at 8:56 PM Dongjin Lee  wrote:
>>
>> > Ismael,
>> >
>> > Oh, I forgot all of you are on working frenzy for 2.0! No problem, take
>> > your time. I am also working at another issue now. Thank you for
>> letting me
>> > know.
>> >
>> > Best,
>> > Dongjin
>> >
>> > On Wed, Jun 13, 2018, 11:44 PM Ismael Juma  wrote:
>> >
>> > > Sorry for the delay Dongjin. Everyone is busy finalising 2.0.0. This
>> KIP
>> > > seems like a great candidate for 2.1.0 and hopefully there will be
>> more
>> > of
>> > > a discussion next week. :)
>> > >
>> > > Ismael
>> > >
>> > > On Wed, 13 Jun 2018, 05:17 Dongjin Lee,  wrote:
>> > >
>> > > > Hello. I just updated my draft implementation:
>> > > >
>> > > > 1. Rebased to latest trunk (commit 5145d6b)
>> > > > 2. Apply ZStd 1.3.4
>> > > >
>> > > > You can check out the implementation from here
>> > > > . If you experience any
>> > > problem
>> > > > running it, don't hesitate to give me a mention.
>> > > >
>> > > > Best,
>> > > > Dongjin
>> > > >
>> > > > On Tue, Jun 12, 2018 at 6:50 PM Dongjin Lee 
>> > wrote:
>> > > >
>> > > > > Here is the short conclusion about the license problem: *We can
>> use
>> > > zstd
>> > > > > and zstd-jni without any problem, but we need to include their
>> > license,
>> > > > > e.g., BSD license.*
>> > > > >
>> > > > > Both of BSD 2 Clause License & 3 Clause License requires to
>> include
>> > the
>> > > > > license used, and BSD 3 Clause License requires that the name of
>> the
>> > > > > contributor can't be used to endorse or promote the product.
>> That's
>> > it
>> > > > > <
>> > > >
>> > >
>> >
>> http://www.mikestratton.net/2011/12/is-bsd-license-compatible-with-apache-2-0-license/
>> > > > >
>> > > > > - They are not listed in the list of prohibited licenses
>> > > > >  also.
>> > > > >
>> > > > > Here is how Spark did for it
>> > > > > :
>> > > > >
>> > > > > - They made a directory dedicated to the dependency license files
>> > > > >  and added
>> > > > licenses
>> > > > > for Zstd
>> > > > > <
>> > https://github.com/apache/spark/blob/master/licenses/LICENSE-zstd.txt
>> > > >
>> > > > &
>> > > > > Zstd-jni
>> > > > > <
>> > 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Dongjin Lee]

Sorry for the late reply.

In short, I could not submit the updated KIP by the feature freeze deadline
of 2.0.0. For this reason, it will not be included in the 2.0.0 release and
all discussion for this issue were postponed after the release of 2.0.0.

I have been updating the PR following recent updates. Just now, I rebased
it against the latest trunk and updated the zstd version into 1.3.5. If you
need some request, don't hesitate to notify me. (But not this thread - just
send me the message directly.)

Best,
Dongjin

On Tue, Jul 10, 2018 at 11:57 PM Bobby Evans  wrote:

> I there any update on this.  The performance improvements are quite
> impressive and I really would like to stop forking kafka just to get this
> in.
>
> Thanks,
>
> Bobby
>
> On Wed, Jun 13, 2018 at 8:56 PM Dongjin Lee  wrote:
>
> > Ismael,
> >
> > Oh, I forgot all of you are on working frenzy for 2.0! No problem, take
> > your time. I am also working at another issue now. Thank you for letting
> me
> > know.
> >
> > Best,
> > Dongjin
> >
> > On Wed, Jun 13, 2018, 11:44 PM Ismael Juma  wrote:
> >
> > > Sorry for the delay Dongjin. Everyone is busy finalising 2.0.0. This
> KIP
> > > seems like a great candidate for 2.1.0 and hopefully there will be more
> > of
> > > a discussion next week. :)
> > >
> > > Ismael
> > >
> > > On Wed, 13 Jun 2018, 05:17 Dongjin Lee,  wrote:
> > >
> > > > Hello. I just updated my draft implementation:
> > > >
> > > > 1. Rebased to latest trunk (commit 5145d6b)
> > > > 2. Apply ZStd 1.3.4
> > > >
> > > > You can check out the implementation from here
> > > > . If you experience any
> > > problem
> > > > running it, don't hesitate to give me a mention.
> > > >
> > > > Best,
> > > > Dongjin
> > > >
> > > > On Tue, Jun 12, 2018 at 6:50 PM Dongjin Lee 
> > wrote:
> > > >
> > > > > Here is the short conclusion about the license problem: *We can use
> > > zstd
> > > > > and zstd-jni without any problem, but we need to include their
> > license,
> > > > > e.g., BSD license.*
> > > > >
> > > > > Both of BSD 2 Clause License & 3 Clause License requires to include
> > the
> > > > > license used, and BSD 3 Clause License requires that the name of
> the
> > > > > contributor can't be used to endorse or promote the product. That's
> > it
> > > > > <
> > > >
> > >
> >
> http://www.mikestratton.net/2011/12/is-bsd-license-compatible-with-apache-2-0-license/
> > > > >
> > > > > - They are not listed in the list of prohibited licenses
> > > > >  also.
> > > > >
> > > > > Here is how Spark did for it
> > > > > :
> > > > >
> > > > > - They made a directory dedicated to the dependency license files
> > > > >  and added
> > > > licenses
> > > > > for Zstd
> > > > > <
> > https://github.com/apache/spark/blob/master/licenses/LICENSE-zstd.txt
> > > >
> > > > &
> > > > > Zstd-jni
> > > > > <
> > > >
> > >
> >
> https://github.com/apache/spark/blob/master/licenses/LICENSE-zstd-jni.txt>
> > > > > .
> > > > > - Added a link to the original license files in LICENSE.
> > > > > 
> > > > >
> > > > > If needed, I can make a similar update.
> > > > >
> > > > > Thanks for pointing out this problem, Viktor! Nice catch!
> > > > >
> > > > > Best,
> > > > > Dongjin
> > > > >
> > > > >
> > > > >
> > > > > On Mon, Jun 11, 2018 at 11:50 PM Dongjin Lee 
> > > wrote:
> > > > >
> > > > >> I greatly appreciate your comprehensive reasoning. so: +1 for b
> > until
> > > > now.
> > > > >>
> > > > >> For the license issues, I will have a check on how the over
> projects
> > > are
> > > > >> doing and share the results.
> > > > >>
> > > > >> Best,
> > > > >> Dongjin
> > > > >>
> > > > >> On Mon, Jun 11, 2018 at 10:08 PM Viktor Somogyi <
> > > > viktorsomo...@gmail.com>
> > > > >> wrote:
> > > > >>
> > > > >>> Hi Dongjin,
> > > > >>>
> > > > >>> A couple of comments:
> > > > >>> I would vote for option b. in the "backward compatibility"
> section.
> > > My
> > > > >>> reasoning for this is that users upgrading to a zstd compatible
> > > version
> > > > >>> won't start to use it automatically, so manual reconfiguration is
> > > > >>> required.
> > > > >>> Therefore an upgrade won't mess up the cluster. If not all the
> > > clients
> > > > >>> are
> > > > >>> upgraded but just some of them and they'd start to use zstd then
> it
> > > > would
> > > > >>> cause errors in the cluster. I'd like to presume though that this
> > is
> > > a
> > > > >>> very
> > > > >>> obvious failure case and nobody should be surprised if it didn't
> > > work.
> > > > >>> I wouldn't choose a. as I think we should bump the fetch and
> > produce
> > > > >>> requests if it's a change in the message format. Moreover if some
> > of
> > > > the
> > > > >>> producers and the brokers are upgraded but some of the consumers
> > are
> > > > not,
> 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Bobby Evans]

I there any update on this.  The performance improvements are quite
impressive and I really would like to stop forking kafka just to get this
in.

Thanks,

Bobby

On Wed, Jun 13, 2018 at 8:56 PM Dongjin Lee  wrote:

> Ismael,
>
> Oh, I forgot all of you are on working frenzy for 2.0! No problem, take
> your time. I am also working at another issue now. Thank you for letting me
> know.
>
> Best,
> Dongjin
>
> On Wed, Jun 13, 2018, 11:44 PM Ismael Juma  wrote:
>
> > Sorry for the delay Dongjin. Everyone is busy finalising 2.0.0. This KIP
> > seems like a great candidate for 2.1.0 and hopefully there will be more
> of
> > a discussion next week. :)
> >
> > Ismael
> >
> > On Wed, 13 Jun 2018, 05:17 Dongjin Lee,  wrote:
> >
> > > Hello. I just updated my draft implementation:
> > >
> > > 1. Rebased to latest trunk (commit 5145d6b)
> > > 2. Apply ZStd 1.3.4
> > >
> > > You can check out the implementation from here
> > > . If you experience any
> > problem
> > > running it, don't hesitate to give me a mention.
> > >
> > > Best,
> > > Dongjin
> > >
> > > On Tue, Jun 12, 2018 at 6:50 PM Dongjin Lee 
> wrote:
> > >
> > > > Here is the short conclusion about the license problem: *We can use
> > zstd
> > > > and zstd-jni without any problem, but we need to include their
> license,
> > > > e.g., BSD license.*
> > > >
> > > > Both of BSD 2 Clause License & 3 Clause License requires to include
> the
> > > > license used, and BSD 3 Clause License requires that the name of the
> > > > contributor can't be used to endorse or promote the product. That's
> it
> > > > <
> > >
> >
> http://www.mikestratton.net/2011/12/is-bsd-license-compatible-with-apache-2-0-license/
> > > >
> > > > - They are not listed in the list of prohibited licenses
> > > >  also.
> > > >
> > > > Here is how Spark did for it
> > > > :
> > > >
> > > > - They made a directory dedicated to the dependency license files
> > > >  and added
> > > licenses
> > > > for Zstd
> > > > <
> https://github.com/apache/spark/blob/master/licenses/LICENSE-zstd.txt
> > >
> > > &
> > > > Zstd-jni
> > > > <
> > >
> >
> https://github.com/apache/spark/blob/master/licenses/LICENSE-zstd-jni.txt>
> > > > .
> > > > - Added a link to the original license files in LICENSE.
> > > > 
> > > >
> > > > If needed, I can make a similar update.
> > > >
> > > > Thanks for pointing out this problem, Viktor! Nice catch!
> > > >
> > > > Best,
> > > > Dongjin
> > > >
> > > >
> > > >
> > > > On Mon, Jun 11, 2018 at 11:50 PM Dongjin Lee 
> > wrote:
> > > >
> > > >> I greatly appreciate your comprehensive reasoning. so: +1 for b
> until
> > > now.
> > > >>
> > > >> For the license issues, I will have a check on how the over projects
> > are
> > > >> doing and share the results.
> > > >>
> > > >> Best,
> > > >> Dongjin
> > > >>
> > > >> On Mon, Jun 11, 2018 at 10:08 PM Viktor Somogyi <
> > > viktorsomo...@gmail.com>
> > > >> wrote:
> > > >>
> > > >>> Hi Dongjin,
> > > >>>
> > > >>> A couple of comments:
> > > >>> I would vote for option b. in the "backward compatibility" section.
> > My
> > > >>> reasoning for this is that users upgrading to a zstd compatible
> > version
> > > >>> won't start to use it automatically, so manual reconfiguration is
> > > >>> required.
> > > >>> Therefore an upgrade won't mess up the cluster. If not all the
> > clients
> > > >>> are
> > > >>> upgraded but just some of them and they'd start to use zstd then it
> > > would
> > > >>> cause errors in the cluster. I'd like to presume though that this
> is
> > a
> > > >>> very
> > > >>> obvious failure case and nobody should be surprised if it didn't
> > work.
> > > >>> I wouldn't choose a. as I think we should bump the fetch and
> produce
> > > >>> requests if it's a change in the message format. Moreover if some
> of
> > > the
> > > >>> producers and the brokers are upgraded but some of the consumers
> are
> > > not,
> > > >>> then we wouldn't prevent the error when the old consumer tries to
> > > consume
> > > >>> the zstd compressed messages.
> > > >>> I wouldn't choose c. either as I think binding the compression type
> > to
> > > an
> > > >>> API is not so obvious from the developer's perspective.
> > > >>>
> > > >>> I would also prefer to use the existing binding, however we must
> > > respect
> > > >>> the licenses:
> > > >>> "The code for these JNI bindings is licenced under 2-clause BSD
> > > license.
> > > >>> The native Zstd library is licensed under 3-clause BSD license and
> > > GPL2"
> > > >>> Based on the FAQ page
> > > >>> https://www.apache.org/legal/resolved.html#category-a
> > > >>> we may use 2- and 3-clause BSD licenses but the Apache license is
> not
> > > >>> compatible with GPL2. I'm hoping that the "3-clause BSD license and
> > > GPL2"
> > > >>> is 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Dongjin Lee]

Ismael,

Oh, I forgot all of you are on working frenzy for 2.0! No problem, take
your time. I am also working at another issue now. Thank you for letting me
know.

Best,
Dongjin

On Wed, Jun 13, 2018, 11:44 PM Ismael Juma  wrote:

> Sorry for the delay Dongjin. Everyone is busy finalising 2.0.0. This KIP
> seems like a great candidate for 2.1.0 and hopefully there will be more of
> a discussion next week. :)
>
> Ismael
>
> On Wed, 13 Jun 2018, 05:17 Dongjin Lee,  wrote:
>
> > Hello. I just updated my draft implementation:
> >
> > 1. Rebased to latest trunk (commit 5145d6b)
> > 2. Apply ZStd 1.3.4
> >
> > You can check out the implementation from here
> > . If you experience any
> problem
> > running it, don't hesitate to give me a mention.
> >
> > Best,
> > Dongjin
> >
> > On Tue, Jun 12, 2018 at 6:50 PM Dongjin Lee  wrote:
> >
> > > Here is the short conclusion about the license problem: *We can use
> zstd
> > > and zstd-jni without any problem, but we need to include their license,
> > > e.g., BSD license.*
> > >
> > > Both of BSD 2 Clause License & 3 Clause License requires to include the
> > > license used, and BSD 3 Clause License requires that the name of the
> > > contributor can't be used to endorse or promote the product. That's it
> > > <
> >
> http://www.mikestratton.net/2011/12/is-bsd-license-compatible-with-apache-2-0-license/
> > >
> > > - They are not listed in the list of prohibited licenses
> > >  also.
> > >
> > > Here is how Spark did for it
> > > :
> > >
> > > - They made a directory dedicated to the dependency license files
> > >  and added
> > licenses
> > > for Zstd
> > >  >
> > &
> > > Zstd-jni
> > > <
> >
> https://github.com/apache/spark/blob/master/licenses/LICENSE-zstd-jni.txt>
> > > .
> > > - Added a link to the original license files in LICENSE.
> > > 
> > >
> > > If needed, I can make a similar update.
> > >
> > > Thanks for pointing out this problem, Viktor! Nice catch!
> > >
> > > Best,
> > > Dongjin
> > >
> > >
> > >
> > > On Mon, Jun 11, 2018 at 11:50 PM Dongjin Lee 
> wrote:
> > >
> > >> I greatly appreciate your comprehensive reasoning. so: +1 for b until
> > now.
> > >>
> > >> For the license issues, I will have a check on how the over projects
> are
> > >> doing and share the results.
> > >>
> > >> Best,
> > >> Dongjin
> > >>
> > >> On Mon, Jun 11, 2018 at 10:08 PM Viktor Somogyi <
> > viktorsomo...@gmail.com>
> > >> wrote:
> > >>
> > >>> Hi Dongjin,
> > >>>
> > >>> A couple of comments:
> > >>> I would vote for option b. in the "backward compatibility" section.
> My
> > >>> reasoning for this is that users upgrading to a zstd compatible
> version
> > >>> won't start to use it automatically, so manual reconfiguration is
> > >>> required.
> > >>> Therefore an upgrade won't mess up the cluster. If not all the
> clients
> > >>> are
> > >>> upgraded but just some of them and they'd start to use zstd then it
> > would
> > >>> cause errors in the cluster. I'd like to presume though that this is
> a
> > >>> very
> > >>> obvious failure case and nobody should be surprised if it didn't
> work.
> > >>> I wouldn't choose a. as I think we should bump the fetch and produce
> > >>> requests if it's a change in the message format. Moreover if some of
> > the
> > >>> producers and the brokers are upgraded but some of the consumers are
> > not,
> > >>> then we wouldn't prevent the error when the old consumer tries to
> > consume
> > >>> the zstd compressed messages.
> > >>> I wouldn't choose c. either as I think binding the compression type
> to
> > an
> > >>> API is not so obvious from the developer's perspective.
> > >>>
> > >>> I would also prefer to use the existing binding, however we must
> > respect
> > >>> the licenses:
> > >>> "The code for these JNI bindings is licenced under 2-clause BSD
> > license.
> > >>> The native Zstd library is licensed under 3-clause BSD license and
> > GPL2"
> > >>> Based on the FAQ page
> > >>> https://www.apache.org/legal/resolved.html#category-a
> > >>> we may use 2- and 3-clause BSD licenses but the Apache license is not
> > >>> compatible with GPL2. I'm hoping that the "3-clause BSD license and
> > GPL2"
> > >>> is really not an AND but an OR in this case, but I'm no lawyer, just
> > >>> wanted
> > >>> to make the point that we should watch out for licenses. :)
> > >>>
> > >>> Regards,
> > >>> Viktor
> > >>>
> > >>>
> > >>> On Sun, Jun 10, 2018 at 3:02 AM Ivan Babrou 
> wrote:
> > >>>
> > >>> > Hello,
> > >>> >
> > >>> > This is Ivan and I still very much support the fact that zstd
> > >>> compression
> > >>> > should be included out of the box.
> > >>> >
> > >>> > Please think about the environment, you can save quite a 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Ismael Juma]

Sorry for the delay Dongjin. Everyone is busy finalising 2.0.0. This KIP
seems like a great candidate for 2.1.0 and hopefully there will be more of
a discussion next week. :)

Ismael

On Wed, 13 Jun 2018, 05:17 Dongjin Lee,  wrote:

> Hello. I just updated my draft implementation:
>
> 1. Rebased to latest trunk (commit 5145d6b)
> 2. Apply ZStd 1.3.4
>
> You can check out the implementation from here
> . If you experience any problem
> running it, don't hesitate to give me a mention.
>
> Best,
> Dongjin
>
> On Tue, Jun 12, 2018 at 6:50 PM Dongjin Lee  wrote:
>
> > Here is the short conclusion about the license problem: *We can use zstd
> > and zstd-jni without any problem, but we need to include their license,
> > e.g., BSD license.*
> >
> > Both of BSD 2 Clause License & 3 Clause License requires to include the
> > license used, and BSD 3 Clause License requires that the name of the
> > contributor can't be used to endorse or promote the product. That's it
> > <
> http://www.mikestratton.net/2011/12/is-bsd-license-compatible-with-apache-2-0-license/
> >
> > - They are not listed in the list of prohibited licenses
> >  also.
> >
> > Here is how Spark did for it
> > :
> >
> > - They made a directory dedicated to the dependency license files
> >  and added
> licenses
> > for Zstd
> > 
> &
> > Zstd-jni
> > <
> https://github.com/apache/spark/blob/master/licenses/LICENSE-zstd-jni.txt>
> > .
> > - Added a link to the original license files in LICENSE.
> > 
> >
> > If needed, I can make a similar update.
> >
> > Thanks for pointing out this problem, Viktor! Nice catch!
> >
> > Best,
> > Dongjin
> >
> >
> >
> > On Mon, Jun 11, 2018 at 11:50 PM Dongjin Lee  wrote:
> >
> >> I greatly appreciate your comprehensive reasoning. so: +1 for b until
> now.
> >>
> >> For the license issues, I will have a check on how the over projects are
> >> doing and share the results.
> >>
> >> Best,
> >> Dongjin
> >>
> >> On Mon, Jun 11, 2018 at 10:08 PM Viktor Somogyi <
> viktorsomo...@gmail.com>
> >> wrote:
> >>
> >>> Hi Dongjin,
> >>>
> >>> A couple of comments:
> >>> I would vote for option b. in the "backward compatibility" section. My
> >>> reasoning for this is that users upgrading to a zstd compatible version
> >>> won't start to use it automatically, so manual reconfiguration is
> >>> required.
> >>> Therefore an upgrade won't mess up the cluster. If not all the clients
> >>> are
> >>> upgraded but just some of them and they'd start to use zstd then it
> would
> >>> cause errors in the cluster. I'd like to presume though that this is a
> >>> very
> >>> obvious failure case and nobody should be surprised if it didn't work.
> >>> I wouldn't choose a. as I think we should bump the fetch and produce
> >>> requests if it's a change in the message format. Moreover if some of
> the
> >>> producers and the brokers are upgraded but some of the consumers are
> not,
> >>> then we wouldn't prevent the error when the old consumer tries to
> consume
> >>> the zstd compressed messages.
> >>> I wouldn't choose c. either as I think binding the compression type to
> an
> >>> API is not so obvious from the developer's perspective.
> >>>
> >>> I would also prefer to use the existing binding, however we must
> respect
> >>> the licenses:
> >>> "The code for these JNI bindings is licenced under 2-clause BSD
> license.
> >>> The native Zstd library is licensed under 3-clause BSD license and
> GPL2"
> >>> Based on the FAQ page
> >>> https://www.apache.org/legal/resolved.html#category-a
> >>> we may use 2- and 3-clause BSD licenses but the Apache license is not
> >>> compatible with GPL2. I'm hoping that the "3-clause BSD license and
> GPL2"
> >>> is really not an AND but an OR in this case, but I'm no lawyer, just
> >>> wanted
> >>> to make the point that we should watch out for licenses. :)
> >>>
> >>> Regards,
> >>> Viktor
> >>>
> >>>
> >>> On Sun, Jun 10, 2018 at 3:02 AM Ivan Babrou  wrote:
> >>>
> >>> > Hello,
> >>> >
> >>> > This is Ivan and I still very much support the fact that zstd
> >>> compression
> >>> > should be included out of the box.
> >>> >
> >>> > Please think about the environment, you can save quite a lot of
> >>> hardware
> >>> > with it.
> >>> >
> >>> > Thank you.
> >>> >
> >>> > On Sat, Jun 9, 2018 at 14:14 Dongjin Lee  wrote:
> >>> >
> >>> > > Since there are no responses for a week, I decided to reinitiate
> the
> >>> > > discussion thread.
> >>> > >
> >>> > >
> >>> > >
> >>> >
> >>>
> https://cwiki.apache.org/confluence/display/KAFKA/KIP-110%3A+Add+Codec+for+ZStandard+Compression
> >>> > >
> >>> > > This KIP is about to introduce ZStandard Compression into Apache
> >>> Kafka.
> >>> > > The reason why it 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Dongjin Lee]

Hello. I just updated my draft implementation:

1. Rebased to latest trunk (commit 5145d6b)
2. Apply ZStd 1.3.4

You can check out the implementation from here
. If you experience any problem
running it, don't hesitate to give me a mention.

Best,
Dongjin

On Tue, Jun 12, 2018 at 6:50 PM Dongjin Lee  wrote:

> Here is the short conclusion about the license problem: *We can use zstd
> and zstd-jni without any problem, but we need to include their license,
> e.g., BSD license.*
>
> Both of BSD 2 Clause License & 3 Clause License requires to include the
> license used, and BSD 3 Clause License requires that the name of the
> contributor can't be used to endorse or promote the product. That's it
> 
> - They are not listed in the list of prohibited licenses
>  also.
>
> Here is how Spark did for it
> :
>
> - They made a directory dedicated to the dependency license files
>  and added licenses
> for Zstd
>  &
> Zstd-jni
> 
> .
> - Added a link to the original license files in LICENSE.
> 
>
> If needed, I can make a similar update.
>
> Thanks for pointing out this problem, Viktor! Nice catch!
>
> Best,
> Dongjin
>
>
>
> On Mon, Jun 11, 2018 at 11:50 PM Dongjin Lee  wrote:
>
>> I greatly appreciate your comprehensive reasoning. so: +1 for b until now.
>>
>> For the license issues, I will have a check on how the over projects are
>> doing and share the results.
>>
>> Best,
>> Dongjin
>>
>> On Mon, Jun 11, 2018 at 10:08 PM Viktor Somogyi 
>> wrote:
>>
>>> Hi Dongjin,
>>>
>>> A couple of comments:
>>> I would vote for option b. in the "backward compatibility" section. My
>>> reasoning for this is that users upgrading to a zstd compatible version
>>> won't start to use it automatically, so manual reconfiguration is
>>> required.
>>> Therefore an upgrade won't mess up the cluster. If not all the clients
>>> are
>>> upgraded but just some of them and they'd start to use zstd then it would
>>> cause errors in the cluster. I'd like to presume though that this is a
>>> very
>>> obvious failure case and nobody should be surprised if it didn't work.
>>> I wouldn't choose a. as I think we should bump the fetch and produce
>>> requests if it's a change in the message format. Moreover if some of the
>>> producers and the brokers are upgraded but some of the consumers are not,
>>> then we wouldn't prevent the error when the old consumer tries to consume
>>> the zstd compressed messages.
>>> I wouldn't choose c. either as I think binding the compression type to an
>>> API is not so obvious from the developer's perspective.
>>>
>>> I would also prefer to use the existing binding, however we must respect
>>> the licenses:
>>> "The code for these JNI bindings is licenced under 2-clause BSD license.
>>> The native Zstd library is licensed under 3-clause BSD license and GPL2"
>>> Based on the FAQ page
>>> https://www.apache.org/legal/resolved.html#category-a
>>> we may use 2- and 3-clause BSD licenses but the Apache license is not
>>> compatible with GPL2. I'm hoping that the "3-clause BSD license and GPL2"
>>> is really not an AND but an OR in this case, but I'm no lawyer, just
>>> wanted
>>> to make the point that we should watch out for licenses. :)
>>>
>>> Regards,
>>> Viktor
>>>
>>>
>>> On Sun, Jun 10, 2018 at 3:02 AM Ivan Babrou  wrote:
>>>
>>> > Hello,
>>> >
>>> > This is Ivan and I still very much support the fact that zstd
>>> compression
>>> > should be included out of the box.
>>> >
>>> > Please think about the environment, you can save quite a lot of
>>> hardware
>>> > with it.
>>> >
>>> > Thank you.
>>> >
>>> > On Sat, Jun 9, 2018 at 14:14 Dongjin Lee  wrote:
>>> >
>>> > > Since there are no responses for a week, I decided to reinitiate the
>>> > > discussion thread.
>>> > >
>>> > >
>>> > >
>>> >
>>> https://cwiki.apache.org/confluence/display/KAFKA/KIP-110%3A+Add+Codec+for+ZStandard+Compression
>>> > >
>>> > > This KIP is about to introduce ZStandard Compression into Apache
>>> Kafka.
>>> > > The reason why it is posted again has a story: It was originally
>>> posted
>>> > to
>>> > > the dev mailing list more than one year ago but since it has no
>>> > performance
>>> > > report included, it was postponed later. But Some people (including
>>> Ivan)
>>> > > reported excellent performance report with the draft PR, this work
>>> is now
>>> > > reactivated.
>>> > >
>>> > > The updated KIP document includes some expected problems and their
>>> > > candidate alternatives. Please have a look when you are free, and
>>> give
>>> > me a
>>> > > 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Dongjin Lee]

Here is the short conclusion about the license problem: *We can use zstd
and zstd-jni without any problem, but we need to include their license,
e.g., BSD license.*

Both of BSD 2 Clause License & 3 Clause License requires to include the
license used, and BSD 3 Clause License requires that the name of the
contributor can't be used to endorse or promote the product. That's it

- They are not listed in the list of prohibited licenses
 also.

Here is how Spark did for it
:

- They made a directory dedicated to the dependency license files
 and added licenses
for Zstd
 &
Zstd-jni
.
- Added a link to the original license files in LICENSE.


If needed, I can make a similar update.

Thanks for pointing out this problem, Viktor! Nice catch!

Best,
Dongjin



On Mon, Jun 11, 2018 at 11:50 PM Dongjin Lee  wrote:

> I greatly appreciate your comprehensive reasoning. so: +1 for b until now.
>
> For the license issues, I will have a check on how the over projects are
> doing and share the results.
>
> Best,
> Dongjin
>
> On Mon, Jun 11, 2018 at 10:08 PM Viktor Somogyi 
> wrote:
>
>> Hi Dongjin,
>>
>> A couple of comments:
>> I would vote for option b. in the "backward compatibility" section. My
>> reasoning for this is that users upgrading to a zstd compatible version
>> won't start to use it automatically, so manual reconfiguration is
>> required.
>> Therefore an upgrade won't mess up the cluster. If not all the clients are
>> upgraded but just some of them and they'd start to use zstd then it would
>> cause errors in the cluster. I'd like to presume though that this is a
>> very
>> obvious failure case and nobody should be surprised if it didn't work.
>> I wouldn't choose a. as I think we should bump the fetch and produce
>> requests if it's a change in the message format. Moreover if some of the
>> producers and the brokers are upgraded but some of the consumers are not,
>> then we wouldn't prevent the error when the old consumer tries to consume
>> the zstd compressed messages.
>> I wouldn't choose c. either as I think binding the compression type to an
>> API is not so obvious from the developer's perspective.
>>
>> I would also prefer to use the existing binding, however we must respect
>> the licenses:
>> "The code for these JNI bindings is licenced under 2-clause BSD license.
>> The native Zstd library is licensed under 3-clause BSD license and GPL2"
>> Based on the FAQ page
>> https://www.apache.org/legal/resolved.html#category-a
>> we may use 2- and 3-clause BSD licenses but the Apache license is not
>> compatible with GPL2. I'm hoping that the "3-clause BSD license and GPL2"
>> is really not an AND but an OR in this case, but I'm no lawyer, just
>> wanted
>> to make the point that we should watch out for licenses. :)
>>
>> Regards,
>> Viktor
>>
>>
>> On Sun, Jun 10, 2018 at 3:02 AM Ivan Babrou  wrote:
>>
>> > Hello,
>> >
>> > This is Ivan and I still very much support the fact that zstd
>> compression
>> > should be included out of the box.
>> >
>> > Please think about the environment, you can save quite a lot of hardware
>> > with it.
>> >
>> > Thank you.
>> >
>> > On Sat, Jun 9, 2018 at 14:14 Dongjin Lee  wrote:
>> >
>> > > Since there are no responses for a week, I decided to reinitiate the
>> > > discussion thread.
>> > >
>> > >
>> > >
>> >
>> https://cwiki.apache.org/confluence/display/KAFKA/KIP-110%3A+Add+Codec+for+ZStandard+Compression
>> > >
>> > > This KIP is about to introduce ZStandard Compression into Apache
>> Kafka.
>> > > The reason why it is posted again has a story: It was originally
>> posted
>> > to
>> > > the dev mailing list more than one year ago but since it has no
>> > performance
>> > > report included, it was postponed later. But Some people (including
>> Ivan)
>> > > reported excellent performance report with the draft PR, this work is
>> now
>> > > reactivated.
>> > >
>> > > The updated KIP document includes some expected problems and their
>> > > candidate alternatives. Please have a look when you are free, and give
>> > me a
>> > > feedback. All kinds of participating are welcome.
>> > >
>> > > Best,
>> > > Dongjin
>> > >
>> > > --
>> > > *Dongjin Lee*
>> > >
>> > > *A hitchhiker in the mathematical world.*
>> > >
>> > > *github:  github.com/dongjinleekr
>> > > linkedin:
>> > kr.linkedin.com/in/dongjinleekr
>> > > slideshare:
>> > www.slideshare.net/dongjinleekr
>> > > *
>> > >
>> >
>>
> --
> *Dongjin Lee*
>

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Dongjin Lee]

I greatly appreciate your comprehensive reasoning. so: +1 for b until now.

For the license issues, I will have a check on how the over projects are
doing and share the results.

Best,
Dongjin

On Mon, Jun 11, 2018 at 10:08 PM Viktor Somogyi 
wrote:

> Hi Dongjin,
>
> A couple of comments:
> I would vote for option b. in the "backward compatibility" section. My
> reasoning for this is that users upgrading to a zstd compatible version
> won't start to use it automatically, so manual reconfiguration is required.
> Therefore an upgrade won't mess up the cluster. If not all the clients are
> upgraded but just some of them and they'd start to use zstd then it would
> cause errors in the cluster. I'd like to presume though that this is a very
> obvious failure case and nobody should be surprised if it didn't work.
> I wouldn't choose a. as I think we should bump the fetch and produce
> requests if it's a change in the message format. Moreover if some of the
> producers and the brokers are upgraded but some of the consumers are not,
> then we wouldn't prevent the error when the old consumer tries to consume
> the zstd compressed messages.
> I wouldn't choose c. either as I think binding the compression type to an
> API is not so obvious from the developer's perspective.
>
> I would also prefer to use the existing binding, however we must respect
> the licenses:
> "The code for these JNI bindings is licenced under 2-clause BSD license.
> The native Zstd library is licensed under 3-clause BSD license and GPL2"
> Based on the FAQ page
> https://www.apache.org/legal/resolved.html#category-a
> we may use 2- and 3-clause BSD licenses but the Apache license is not
> compatible with GPL2. I'm hoping that the "3-clause BSD license and GPL2"
> is really not an AND but an OR in this case, but I'm no lawyer, just wanted
> to make the point that we should watch out for licenses. :)
>
> Regards,
> Viktor
>
>
> On Sun, Jun 10, 2018 at 3:02 AM Ivan Babrou  wrote:
>
> > Hello,
> >
> > This is Ivan and I still very much support the fact that zstd compression
> > should be included out of the box.
> >
> > Please think about the environment, you can save quite a lot of hardware
> > with it.
> >
> > Thank you.
> >
> > On Sat, Jun 9, 2018 at 14:14 Dongjin Lee  wrote:
> >
> > > Since there are no responses for a week, I decided to reinitiate the
> > > discussion thread.
> > >
> > >
> > >
> >
> https://cwiki.apache.org/confluence/display/KAFKA/KIP-110%3A+Add+Codec+for+ZStandard+Compression
> > >
> > > This KIP is about to introduce ZStandard Compression into Apache Kafka.
> > > The reason why it is posted again has a story: It was originally posted
> > to
> > > the dev mailing list more than one year ago but since it has no
> > performance
> > > report included, it was postponed later. But Some people (including
> Ivan)
> > > reported excellent performance report with the draft PR, this work is
> now
> > > reactivated.
> > >
> > > The updated KIP document includes some expected problems and their
> > > candidate alternatives. Please have a look when you are free, and give
> > me a
> > > feedback. All kinds of participating are welcome.
> > >
> > > Best,
> > > Dongjin
> > >
> > > --
> > > *Dongjin Lee*
> > >
> > > *A hitchhiker in the mathematical world.*
> > >
> > > *github:  github.com/dongjinleekr
> > > linkedin:
> > kr.linkedin.com/in/dongjinleekr
> > > slideshare:
> > www.slideshare.net/dongjinleekr
> > > *
> > >
> >
>
-- 
*Dongjin Lee*

*A hitchhiker in the mathematical world.*

*github:  github.com/dongjinleekr
linkedin: kr.linkedin.com/in/dongjinleekr
slideshare:
www.slideshare.net/dongjinleekr
*

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Viktor Somogyi]

Hi Dongjin,

A couple of comments:
I would vote for option b. in the "backward compatibility" section. My
reasoning for this is that users upgrading to a zstd compatible version
won't start to use it automatically, so manual reconfiguration is required.
Therefore an upgrade won't mess up the cluster. If not all the clients are
upgraded but just some of them and they'd start to use zstd then it would
cause errors in the cluster. I'd like to presume though that this is a very
obvious failure case and nobody should be surprised if it didn't work.
I wouldn't choose a. as I think we should bump the fetch and produce
requests if it's a change in the message format. Moreover if some of the
producers and the brokers are upgraded but some of the consumers are not,
then we wouldn't prevent the error when the old consumer tries to consume
the zstd compressed messages.
I wouldn't choose c. either as I think binding the compression type to an
API is not so obvious from the developer's perspective.

I would also prefer to use the existing binding, however we must respect
the licenses:
"The code for these JNI bindings is licenced under 2-clause BSD license.
The native Zstd library is licensed under 3-clause BSD license and GPL2"
Based on the FAQ page https://www.apache.org/legal/resolved.html#category-a
we may use 2- and 3-clause BSD licenses but the Apache license is not
compatible with GPL2. I'm hoping that the "3-clause BSD license and GPL2"
is really not an AND but an OR in this case, but I'm no lawyer, just wanted
to make the point that we should watch out for licenses. :)

Regards,
Viktor


On Sun, Jun 10, 2018 at 3:02 AM Ivan Babrou  wrote:

> Hello,
>
> This is Ivan and I still very much support the fact that zstd compression
> should be included out of the box.
>
> Please think about the environment, you can save quite a lot of hardware
> with it.
>
> Thank you.
>
> On Sat, Jun 9, 2018 at 14:14 Dongjin Lee  wrote:
>
> > Since there are no responses for a week, I decided to reinitiate the
> > discussion thread.
> >
> >
> >
> https://cwiki.apache.org/confluence/display/KAFKA/KIP-110%3A+Add+Codec+for+ZStandard+Compression
> >
> > This KIP is about to introduce ZStandard Compression into Apache Kafka.
> > The reason why it is posted again has a story: It was originally posted
> to
> > the dev mailing list more than one year ago but since it has no
> performance
> > report included, it was postponed later. But Some people (including Ivan)
> > reported excellent performance report with the draft PR, this work is now
> > reactivated.
> >
> > The updated KIP document includes some expected problems and their
> > candidate alternatives. Please have a look when you are free, and give
> me a
> > feedback. All kinds of participating are welcome.
> >
> > Best,
> > Dongjin
> >
> > --
> > *Dongjin Lee*
> >
> > *A hitchhiker in the mathematical world.*
> >
> > *github:  github.com/dongjinleekr
> > linkedin:
> kr.linkedin.com/in/dongjinleekr
> > slideshare:
> www.slideshare.net/dongjinleekr
> > *
> >
>

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Ivan Babrou]

Hello,

This is Ivan and I still very much support the fact that zstd compression
should be included out of the box.

Please think about the environment, you can save quite a lot of hardware
with it.

Thank you.

On Sat, Jun 9, 2018 at 14:14 Dongjin Lee  wrote:

> Since there are no responses for a week, I decided to reinitiate the
> discussion thread.
>
>
> https://cwiki.apache.org/confluence/display/KAFKA/KIP-110%3A+Add+Codec+for+ZStandard+Compression
>
> This KIP is about to introduce ZStandard Compression into Apache Kafka.
> The reason why it is posted again has a story: It was originally posted to
> the dev mailing list more than one year ago but since it has no performance
> report included, it was postponed later. But Some people (including Ivan)
> reported excellent performance report with the draft PR, this work is now
> reactivated.
>
> The updated KIP document includes some expected problems and their
> candidate alternatives. Please have a look when you are free, and give me a
> feedback. All kinds of participating are welcome.
>
> Best,
> Dongjin
>
> --
> *Dongjin Lee*
>
> *A hitchhiker in the mathematical world.*
>
> *github:  github.com/dongjinleekr
> linkedin: kr.linkedin.com/in/dongjinleekr
> slideshare: 
> www.slideshare.net/dongjinleekr
> *
>

[DISCUSS] KIP-110: Add Codec for ZStandard Compression (Updated)

[Dongjin Lee]

Since there are no responses for a week, I decided to reinitiate the
discussion thread.

https://cwiki.apache.org/confluence/display/KAFKA/KIP-110%3A+Add+Codec+for+ZStandard+Compression

This KIP is about to introduce ZStandard Compression into Apache Kafka. The
reason why it is posted again has a story: It was originally posted to the
dev mailing list more than one year ago but since it has no performance
report included, it was postponed later. But Some people (including Ivan)
reported excellent performance report with the draft PR, this work is now
reactivated.

The updated KIP document includes some expected problems and their
candidate alternatives. Please have a look when you are free, and give me a
feedback. All kinds of participating are welcome.

Best,
Dongjin

-- 
*Dongjin Lee*

*A hitchhiker in the mathematical world.*

*github:  github.com/dongjinleekr
linkedin: kr.linkedin.com/in/dongjinleekr
slideshare:
www.slideshare.net/dongjinleekr
*

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression

[Dongjin Lee]

mpressionType.
> > > [^2]: There is similar routine in Message.scala. But after KAFKA-4390,
> > > that routine is not being used anymore - more precisely, Message class
> is
> > > now used in ConsoleConsumer only. I think this class should be replaced
> > but
> > > since it is a separated topic, I will send another message for this
> > issue.
> > > [^3]: commit 642da2f (2011.8.2).
> > > [^4]: commit c51b940.
> > > [^5]: commit 547cced.
> > > [^6]: commit 37356bf.
> > >
> > > On Thu, Jan 26, 2017 at 12:35 AM, Ismael Juma 
> wrote:
> > >
> > >> So far the discussion was around the performance characteristics of
> the
> > >> new
> > >> compression algorithm. Another area that is important and is not
> covered
> > >> in
> > >> the KIP is the compatibility implications. For example, what happens
> if
> > a
> > >> consumer that doesn't support zstd tries to consume a topic compressed
> > >> with
> > >> it? Or if a broker that doesn't support receives data compressed with
> > it?
> > >> If we go through that exercise, then more changes may be required
> (like
> > >> bumping the version of produce/fetch protocols).
> > >>
> > >> Ismael
> > >>
> > >> On Wed, Jan 25, 2017 at 3:22 PM, Ben Stopford 
> wrote:
> > >>
> > >> > Is there more discussion to be had on this KIP, or should it be
> taken
> > >> to a
> > >> > vote?
> > >> >
> > >> > On Mon, Jan 16, 2017 at 6:37 AM Dongjin Lee 
> > wrote:
> > >> >
> > >> > > I updated KIP-110 with JMH-measured benchmark results. Please
> have a
> > >> > review
> > >> > > when you are free. (The overall result is not different yet.)
> > >> > >
> > >> > > Regards,
> > >> > > Dongjin
> > >> > >
> > >> > > +1. Could anyone assign KAFKA-4514 to me?
> > >> > >
> > >> > > On Thu, Jan 12, 2017 at 11:39 AM, Dongjin Lee  >
> > >> > wrote:
> > >> > >
> > >> > > > Okay, I will have a try.
> > >> > > > Thanks Ewen for the guidance!!
> > >> > > >
> > >> > > > Best,
> > >> > > > Dongjin
> > >> > > >
> > >> > > > On Thu, Jan 12, 2017 at 6:44 AM, Ismael Juma  >
> > >> > wrote:
> > >> > > >
> > >> > > >> That's a good point Ewen. Dongjin, you could use the branch
> that
> > >> Ewen
> > >> > > >> linked for the performance testing. It would also help validate
> > the
> > >> > PR.
> > >> > > >>
> > >> > > >> Ismael
> > >> > > >>
> > >> > > >> On Wed, Jan 11, 2017 at 9:38 PM, Ewen Cheslack-Postava <
> > >> > > e...@confluent.io
> > >> > > >> >
> > >> > > >> wrote:
> > >> > > >>
> > >> > > >> > FYI, there's an outstanding patch for getting some JMH
> > >> benchmarking
> > >> > > >> setup:
> > >> > > >> > https://github.com/apache/kafka/pull/1712 I haven't found
> time
> > >> to
> > >> > > >> review
> > >> > > >> > it
> > >> > > >> > (and don't really know JMH well anyway) but it might be worth
> > >> > getting
> > >> > > >> that
> > >> > > >> > landed so we can use it for this as well.
> > >> > > >> >
> > >> > > >> > -Ewen
> > >> > > >> >
> > >> > > >> > On Wed, Jan 11, 2017 at 6:35 AM, Dongjin Lee <
> > dong...@apache.org
> > >> >
> > >> > > >> wrote:
> > >> > > >> >
> > >> > > >> > > Hi Ismael,
> > >> > > >> > >
> > >> > > >> > > 1. In the case of compression output, yes, lz4 is producing
> > the
> > >> > > >> smaller
> > >> > > >> > > output than gzip. In fact, my benchmark was inspired
> > >> > > >> > > by MessageCompressionTes

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression

[Jeff Widman]

t support zstd tries to consume a topic compressed
> >> with
> >> it? Or if a broker that doesn't support receives data compressed with
> it?
> >> If we go through that exercise, then more changes may be required (like
> >> bumping the version of produce/fetch protocols).
> >>
> >> Ismael
> >>
> >> On Wed, Jan 25, 2017 at 3:22 PM, Ben Stopford <b...@confluent.io> wrote:
> >>
> >> > Is there more discussion to be had on this KIP, or should it be taken
> >> to a
> >> > vote?
> >> >
> >> > On Mon, Jan 16, 2017 at 6:37 AM Dongjin Lee <dong...@apache.org>
> wrote:
> >> >
> >> > > I updated KIP-110 with JMH-measured benchmark results. Please have a
> >> > review
> >> > > when you are free. (The overall result is not different yet.)
> >> > >
> >> > > Regards,
> >> > > Dongjin
> >> > >
> >> > > +1. Could anyone assign KAFKA-4514 to me?
> >> > >
> >> > > On Thu, Jan 12, 2017 at 11:39 AM, Dongjin Lee <dong...@apache.org>
> >> > wrote:
> >> > >
> >> > > > Okay, I will have a try.
> >> > > > Thanks Ewen for the guidance!!
> >> > > >
> >> > > > Best,
> >> > > > Dongjin
> >> > > >
> >> > > > On Thu, Jan 12, 2017 at 6:44 AM, Ismael Juma <ism...@juma.me.uk>
> >> > wrote:
> >> > > >
> >> > > >> That's a good point Ewen. Dongjin, you could use the branch that
> >> Ewen
> >> > > >> linked for the performance testing. It would also help validate
> the
> >> > PR.
> >> > > >>
> >> > > >> Ismael
> >> > > >>
> >> > > >> On Wed, Jan 11, 2017 at 9:38 PM, Ewen Cheslack-Postava <
> >> > > e...@confluent.io
> >> > > >> >
> >> > > >> wrote:
> >> > > >>
> >> > > >> > FYI, there's an outstanding patch for getting some JMH
> >> benchmarking
> >> > > >> setup:
> >> > > >> > https://github.com/apache/kafka/pull/1712 I haven't found time
> >> to
> >> > > >> review
> >> > > >> > it
> >> > > >> > (and don't really know JMH well anyway) but it might be worth
> >> > getting
> >> > > >> that
> >> > > >> > landed so we can use it for this as well.
> >> > > >> >
> >> > > >> > -Ewen
> >> > > >> >
> >> > > >> > On Wed, Jan 11, 2017 at 6:35 AM, Dongjin Lee <
> dong...@apache.org
> >> >
> >> > > >> wrote:
> >> > > >> >
> >> > > >> > > Hi Ismael,
> >> > > >> > >
> >> > > >> > > 1. In the case of compression output, yes, lz4 is producing
> the
> >> > > >> smaller
> >> > > >> > > output than gzip. In fact, my benchmark was inspired
> >> > > >> > > by MessageCompressionTest#testCompressSize unit test and the
> >> > result
> >> > > >> is
> >> > > >> > > same - 396 bytes for gzip and 387 bytes for lz4.
> >> > > >> > > 2. I agree that my (former) approach can result in unreliable
> >> > > output.
> >> > > >> > > However, I am experiencing difficulties on how to acquire the
> >> > > >> benchmark
> >> > > >> > > metrics from Kafka. For you recommended JMH, I just started
> to
> >> > > google
> >> > > >> for
> >> > > >> > > it. If possible, could you give any example on how to use JMH
> >> > > against
> >> > > >> > > Kafka? If it is the case, it will be a great help.
> >> > > >> > > Regards,Dongjin
> >> > > >> > >
> >> > > >> > > _
> >> > > >> > > From: Ismael Juma <ism...@juma.me.uk>
> >> > > >> > > Sent: Wednesday, January 11, 2017 7:33 PM
> >> > > >> > > Subject: Re: [DISCUSS] KIP-110: Add C

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression

[Ewen Cheslack-Postava]

roduce/fetch protocols).
>> >>
>> >> Ismael
>> >>
>> >> On Wed, Jan 25, 2017 at 3:22 PM, Ben Stopford <b...@confluent.io>
>> wrote:
>> >>
>> >> > Is there more discussion to be had on this KIP, or should it be taken
>> >> to a
>> >> > vote?
>> >> >
>> >> > On Mon, Jan 16, 2017 at 6:37 AM Dongjin Lee <dong...@apache.org>
>> wrote:
>> >> >
>> >> > > I updated KIP-110 with JMH-measured benchmark results. Please have
>> a
>> >> > review
>> >> > > when you are free. (The overall result is not different yet.)
>> >> > >
>> >> > > Regards,
>> >> > > Dongjin
>> >> > >
>> >> > > +1. Could anyone assign KAFKA-4514 to me?
>> >> > >
>> >> > > On Thu, Jan 12, 2017 at 11:39 AM, Dongjin Lee <dong...@apache.org>
>> >> > wrote:
>> >> > >
>> >> > > > Okay, I will have a try.
>> >> > > > Thanks Ewen for the guidance!!
>> >> > > >
>> >> > > > Best,
>> >> > > > Dongjin
>> >> > > >
>> >> > > > On Thu, Jan 12, 2017 at 6:44 AM, Ismael Juma <ism...@juma.me.uk>
>> >> > wrote:
>> >> > > >
>> >> > > >> That's a good point Ewen. Dongjin, you could use the branch that
>> >> Ewen
>> >> > > >> linked for the performance testing. It would also help validate
>> the
>> >> > PR.
>> >> > > >>
>> >> > > >> Ismael
>> >> > > >>
>> >> > > >> On Wed, Jan 11, 2017 at 9:38 PM, Ewen Cheslack-Postava <
>> >> > > e...@confluent.io
>> >> > > >> >
>> >> > > >> wrote:
>> >> > > >>
>> >> > > >> > FYI, there's an outstanding patch for getting some JMH
>> >> benchmarking
>> >> > > >> setup:
>> >> > > >> > https://github.com/apache/kafka/pull/1712 I haven't found
>> time
>> >> to
>> >> > > >> review
>> >> > > >> > it
>> >> > > >> > (and don't really know JMH well anyway) but it might be worth
>> >> > getting
>> >> > > >> that
>> >> > > >> > landed so we can use it for this as well.
>> >> > > >> >
>> >> > > >> > -Ewen
>> >> > > >> >
>> >> > > >> > On Wed, Jan 11, 2017 at 6:35 AM, Dongjin Lee <
>> dong...@apache.org
>> >> >
>> >> > > >> wrote:
>> >> > > >> >
>> >> > > >> > > Hi Ismael,
>> >> > > >> > >
>> >> > > >> > > 1. In the case of compression output, yes, lz4 is producing
>> the
>> >> > > >> smaller
>> >> > > >> > > output than gzip. In fact, my benchmark was inspired
>> >> > > >> > > by MessageCompressionTest#testCompressSize unit test and
>> the
>> >> > result
>> >> > > >> is
>> >> > > >> > > same - 396 bytes for gzip and 387 bytes for lz4.
>> >> > > >> > > 2. I agree that my (former) approach can result in
>> unreliable
>> >> > > output.
>> >> > > >> > > However, I am experiencing difficulties on how to acquire
>> the
>> >> > > >> benchmark
>> >> > > >> > > metrics from Kafka. For you recommended JMH, I just started
>> to
>> >> > > google
>> >> > > >> for
>> >> > > >> > > it. If possible, could you give any example on how to use
>> JMH
>> >> > > against
>> >> > > >> > > Kafka? If it is the case, it will be a great help.
>> >> > > >> > > Regards,Dongjin
>> >> > > >> > >
>> >> > > >> > > _
>> >> > > >> > > From: Ismael Juma <ism...@juma.me.uk>
>> >> > > >> > > Sent: Wednesday, Jan

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression

[Dongjin Lee]

; >> > > Dongjin
> >> > >
> >> > > +1. Could anyone assign KAFKA-4514 to me?
> >> > >
> >> > > On Thu, Jan 12, 2017 at 11:39 AM, Dongjin Lee <dong...@apache.org>
> >> > wrote:
> >> > >
> >> > > > Okay, I will have a try.
> >> > > > Thanks Ewen for the guidance!!
> >> > > >
> >> > > > Best,
> >> > > > Dongjin
> >> > > >
> >> > > > On Thu, Jan 12, 2017 at 6:44 AM, Ismael Juma <ism...@juma.me.uk>
> >> > wrote:
> >> > > >
> >> > > >> That's a good point Ewen. Dongjin, you could use the branch that
> >> Ewen
> >> > > >> linked for the performance testing. It would also help validate
> the
> >> > PR.
> >> > > >>
> >> > > >> Ismael
> >> > > >>
> >> > > >> On Wed, Jan 11, 2017 at 9:38 PM, Ewen Cheslack-Postava <
> >> > > e...@confluent.io
> >> > > >> >
> >> > > >> wrote:
> >> > > >>
> >> > > >> > FYI, there's an outstanding patch for getting some JMH
> >> benchmarking
> >> > > >> setup:
> >> > > >> > https://github.com/apache/kafka/pull/1712 I haven't found time
> >> to
> >> > > >> review
> >> > > >> > it
> >> > > >> > (and don't really know JMH well anyway) but it might be worth
> >> > getting
> >> > > >> that
> >> > > >> > landed so we can use it for this as well.
> >> > > >> >
> >> > > >> > -Ewen
> >> > > >> >
> >> > > >> > On Wed, Jan 11, 2017 at 6:35 AM, Dongjin Lee <
> dong...@apache.org
> >> >
> >> > > >> wrote:
> >> > > >> >
> >> > > >> > > Hi Ismael,
> >> > > >> > >
> >> > > >> > > 1. In the case of compression output, yes, lz4 is producing
> the
> >> > > >> smaller
> >> > > >> > > output than gzip. In fact, my benchmark was inspired
> >> > > >> > > by MessageCompressionTest#testCompressSize unit test and the
> >> > result
> >> > > >> is
> >> > > >> > > same - 396 bytes for gzip and 387 bytes for lz4.
> >> > > >> > > 2. I agree that my (former) approach can result in unreliable
> >> > > output.
> >> > > >> > > However, I am experiencing difficulties on how to acquire the
> >> > > >> benchmark
> >> > > >> > > metrics from Kafka. For you recommended JMH, I just started
> to
> >> > > google
> >> > > >> for
> >> > > >> > > it. If possible, could you give any example on how to use JMH
> >> > > against
> >> > > >> > > Kafka? If it is the case, it will be a great help.
> >> > > >> > > Regards,Dongjin
> >> > > >> > >
> >> > > >> > > _
> >> > > >> > > From: Ismael Juma <ism...@juma.me.uk>
> >> > > >> > > Sent: Wednesday, January 11, 2017 7:33 PM
> >> > > >> > > Subject: Re: [DISCUSS] KIP-110: Add Codec for ZStandard
> >> > Compression
> >> > > >> > > To:  <dev@kafka.apache.org>
> >> > > >> > >
> >> > > >> > >
> >> > > >> > > Thanks Dongjin. I highly recommend using JMH for the
> benchmark,
> >> > the
> >> > > >> > > existing one has a few problems that could result in
> unreliable
> >> > > >> results.
> >> > > >> > > Also, it's a bit surprising that LZ4 is producing smaller
> >> output
> >> > > than
> >> > > >> > gzip.
> >> > > >> > > Is that right?
> >> > > >> > >
> >> > > >> > > Ismael
> >> > > >> > >
> >> > > >> > > On Wed, Jan 11, 2017 at 10:20 AM, Dongjin Lee <
> >> dong...@apache.org
> >> >

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression

[Ismael Juma]

> >> bumping the version of produce/fetch protocols).
> >>
> >> Ismael
> >>
> >> On Wed, Jan 25, 2017 at 3:22 PM, Ben Stopford <b...@confluent.io> wrote:
> >>
> >> > Is there more discussion to be had on this KIP, or should it be taken
> >> to a
> >> > vote?
> >> >
> >> > On Mon, Jan 16, 2017 at 6:37 AM Dongjin Lee <dong...@apache.org>
> wrote:
> >> >
> >> > > I updated KIP-110 with JMH-measured benchmark results. Please have a
> >> > review
> >> > > when you are free. (The overall result is not different yet.)
> >> > >
> >> > > Regards,
> >> > > Dongjin
> >> > >
> >> > > +1. Could anyone assign KAFKA-4514 to me?
> >> > >
> >> > > On Thu, Jan 12, 2017 at 11:39 AM, Dongjin Lee <dong...@apache.org>
> >> > wrote:
> >> > >
> >> > > > Okay, I will have a try.
> >> > > > Thanks Ewen for the guidance!!
> >> > > >
> >> > > > Best,
> >> > > > Dongjin
> >> > > >
> >> > > > On Thu, Jan 12, 2017 at 6:44 AM, Ismael Juma <ism...@juma.me.uk>
> >> > wrote:
> >> > > >
> >> > > >> That's a good point Ewen. Dongjin, you could use the branch that
> >> Ewen
> >> > > >> linked for the performance testing. It would also help validate
> the
> >> > PR.
> >> > > >>
> >> > > >> Ismael
> >> > > >>
> >> > > >> On Wed, Jan 11, 2017 at 9:38 PM, Ewen Cheslack-Postava <
> >> > > e...@confluent.io
> >> > > >> >
> >> > > >> wrote:
> >> > > >>
> >> > > >> > FYI, there's an outstanding patch for getting some JMH
> >> benchmarking
> >> > > >> setup:
> >> > > >> > https://github.com/apache/kafka/pull/1712 I haven't found time
> >> to
> >> > > >> review
> >> > > >> > it
> >> > > >> > (and don't really know JMH well anyway) but it might be worth
> >> > getting
> >> > > >> that
> >> > > >> > landed so we can use it for this as well.
> >> > > >> >
> >> > > >> > -Ewen
> >> > > >> >
> >> > > >> > On Wed, Jan 11, 2017 at 6:35 AM, Dongjin Lee <
> dong...@apache.org
> >> >
> >> > > >> wrote:
> >> > > >> >
> >> > > >> > > Hi Ismael,
> >> > > >> > >
> >> > > >> > > 1. In the case of compression output, yes, lz4 is producing
> the
> >> > > >> smaller
> >> > > >> > > output than gzip. In fact, my benchmark was inspired
> >> > > >> > > by MessageCompressionTest#testCompressSize unit test and the
> >> > result
> >> > > >> is
> >> > > >> > > same - 396 bytes for gzip and 387 bytes for lz4.
> >> > > >> > > 2. I agree that my (former) approach can result in unreliable
> >> > > output.
> >> > > >> > > However, I am experiencing difficulties on how to acquire the
> >> > > >> benchmark
> >> > > >> > > metrics from Kafka. For you recommended JMH, I just started
> to
> >> > > google
> >> > > >> for
> >> > > >> > > it. If possible, could you give any example on how to use JMH
> >> > > against
> >> > > >> > > Kafka? If it is the case, it will be a great help.
> >> > > >> > > Regards,Dongjin
> >> > > >> > >
> >> > > >> > > _
> >> > > >> > > From: Ismael Juma <ism...@juma.me.uk>
> >> > > >> > > Sent: Wednesday, January 11, 2017 7:33 PM
> >> > > >> > > Subject: Re: [DISCUSS] KIP-110: Add Codec for ZStandard
> >> > Compression
> >> > > >> > > To:  <dev@kafka.apache.org>
> >> > > >> > >
> >> > > >> > >
> >> > > >> > > Thanks Dongjin. I 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression

[Ismael Juma]

t;> > > >> linked for the performance testing. It would also help validate the
>> > PR.
>> > > >>
>> > > >> Ismael
>> > > >>
>> > > >> On Wed, Jan 11, 2017 at 9:38 PM, Ewen Cheslack-Postava <
>> > > e...@confluent.io
>> > > >> >
>> > > >> wrote:
>> > > >>
>> > > >> > FYI, there's an outstanding patch for getting some JMH
>> benchmarking
>> > > >> setup:
>> > > >> > https://github.com/apache/kafka/pull/1712 I haven't found time
>> to
>> > > >> review
>> > > >> > it
>> > > >> > (and don't really know JMH well anyway) but it might be worth
>> > getting
>> > > >> that
>> > > >> > landed so we can use it for this as well.
>> > > >> >
>> > > >> > -Ewen
>> > > >> >
>> > > >> > On Wed, Jan 11, 2017 at 6:35 AM, Dongjin Lee <dong...@apache.org
>> >
>> > > >> wrote:
>> > > >> >
>> > > >> > > Hi Ismael,
>> > > >> > >
>> > > >> > > 1. In the case of compression output, yes, lz4 is producing the
>> > > >> smaller
>> > > >> > > output than gzip. In fact, my benchmark was inspired
>> > > >> > > by MessageCompressionTest#testCompressSize unit test and the
>> > result
>> > > >> is
>> > > >> > > same - 396 bytes for gzip and 387 bytes for lz4.
>> > > >> > > 2. I agree that my (former) approach can result in unreliable
>> > > output.
>> > > >> > > However, I am experiencing difficulties on how to acquire the
>> > > >> benchmark
>> > > >> > > metrics from Kafka. For you recommended JMH, I just started to
>> > > google
>> > > >> for
>> > > >> > > it. If possible, could you give any example on how to use JMH
>> > > against
>> > > >> > > Kafka? If it is the case, it will be a great help.
>> > > >> > > Regards,Dongjin
>> > > >> > >
>> > > >> > > _
>> > > >> > > From: Ismael Juma <ism...@juma.me.uk>
>> > > >> > > Sent: Wednesday, January 11, 2017 7:33 PM
>> > > >> > > Subject: Re: [DISCUSS] KIP-110: Add Codec for ZStandard
>> > Compression
>> > > >> > > To:  <dev@kafka.apache.org>
>> > > >> > >
>> > > >> > >
>> > > >> > > Thanks Dongjin. I highly recommend using JMH for the benchmark,
>> > the
>> > > >> > > existing one has a few problems that could result in unreliable
>> > > >> results.
>> > > >> > > Also, it's a bit surprising that LZ4 is producing smaller
>> output
>> > > than
>> > > >> > gzip.
>> > > >> > > Is that right?
>> > > >> > >
>> > > >> > > Ismael
>> > > >> > >
>> > > >> > > On Wed, Jan 11, 2017 at 10:20 AM, Dongjin Lee <
>> dong...@apache.org
>> > >
>> > > >> > wrote:
>> > > >> > >
>> > > >> > > > Ismael,
>> > > >> > > >
>> > > >> > > > I pushed the benchmark code I used, with some updates
>> > (iteration:
>> > > >> 20 ->
>> > > >> > > > 1000). I also updated the KIP page with the updated benchmark
>> > > >> results.
>> > > >> > > > Please take a review when you are free. The attached
>> screenshot
>> > > >> shows
>> > > >> > how
>> > > >> > > > to run the benchmarker.
>> > > >> > > >
>> > > >> > > > Thanks,
>> > > >> > > > Dongjin
>> > > >> > > >
>> > > >> > > > On Tue, Jan 10, 2017 at 8:03 PM, Dongjin Lee <
>> > dong...@apache.org>
>> > > >> > wrote:
>> > > >> > > >
>> > > >> > > >> Ismael,
>> > >

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression

[Magnus Edenhill]

> wrote:
>> > >
>> > > > Okay, I will have a try.
>> > > > Thanks Ewen for the guidance!!
>> > > >
>> > > > Best,
>> > > > Dongjin
>> > > >
>> > > > On Thu, Jan 12, 2017 at 6:44 AM, Ismael Juma <ism...@juma.me.uk>
>> > wrote:
>> > > >
>> > > >> That's a good point Ewen. Dongjin, you could use the branch that
>> Ewen
>> > > >> linked for the performance testing. It would also help validate the
>> > PR.
>> > > >>
>> > > >> Ismael
>> > > >>
>> > > >> On Wed, Jan 11, 2017 at 9:38 PM, Ewen Cheslack-Postava <
>> > > e...@confluent.io
>> > > >> >
>> > > >> wrote:
>> > > >>
>> > > >> > FYI, there's an outstanding patch for getting some JMH
>> benchmarking
>> > > >> setup:
>> > > >> > https://github.com/apache/kafka/pull/1712 I haven't found time
>> to
>> > > >> review
>> > > >> > it
>> > > >> > (and don't really know JMH well anyway) but it might be worth
>> > getting
>> > > >> that
>> > > >> > landed so we can use it for this as well.
>> > > >> >
>> > > >> > -Ewen
>> > > >> >
>> > > >> > On Wed, Jan 11, 2017 at 6:35 AM, Dongjin Lee <dong...@apache.org
>> >
>> > > >> wrote:
>> > > >> >
>> > > >> > > Hi Ismael,
>> > > >> > >
>> > > >> > > 1. In the case of compression output, yes, lz4 is producing the
>> > > >> smaller
>> > > >> > > output than gzip. In fact, my benchmark was inspired
>> > > >> > > by MessageCompressionTest#testCompressSize unit test and the
>> > result
>> > > >> is
>> > > >> > > same - 396 bytes for gzip and 387 bytes for lz4.
>> > > >> > > 2. I agree that my (former) approach can result in unreliable
>> > > output.
>> > > >> > > However, I am experiencing difficulties on how to acquire the
>> > > >> benchmark
>> > > >> > > metrics from Kafka. For you recommended JMH, I just started to
>> > > google
>> > > >> for
>> > > >> > > it. If possible, could you give any example on how to use JMH
>> > > against
>> > > >> > > Kafka? If it is the case, it will be a great help.
>> > > >> > > Regards,Dongjin
>> > > >> > >
>> > > >> > > _
>> > > >> > > From: Ismael Juma <ism...@juma.me.uk>
>> > > >> > > Sent: Wednesday, January 11, 2017 7:33 PM
>> > > >> > > Subject: Re: [DISCUSS] KIP-110: Add Codec for ZStandard
>> > Compression
>> > > >> > > To:  <dev@kafka.apache.org>
>> > > >> > >
>> > > >> > >
>> > > >> > > Thanks Dongjin. I highly recommend using JMH for the benchmark,
>> > the
>> > > >> > > existing one has a few problems that could result in unreliable
>> > > >> results.
>> > > >> > > Also, it's a bit surprising that LZ4 is producing smaller
>> output
>> > > than
>> > > >> > gzip.
>> > > >> > > Is that right?
>> > > >> > >
>> > > >> > > Ismael
>> > > >> > >
>> > > >> > > On Wed, Jan 11, 2017 at 10:20 AM, Dongjin Lee <
>> dong...@apache.org
>> > >
>> > > >> > wrote:
>> > > >> > >
>> > > >> > > > Ismael,
>> > > >> > > >
>> > > >> > > > I pushed the benchmark code I used, with some updates
>> > (iteration:
>> > > >> 20 ->
>> > > >> > > > 1000). I also updated the KIP page with the updated benchmark
>> > > >> results.
>> > > >> > > > Please take a review when you are free. The attached
>> screenshot
>> > > >> shows
>> > > >> > how
>> &

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression

[Dongjin Lee]

 as well.
> > > >> >
> > > >> > -Ewen
> > > >> >
> > > >> > On Wed, Jan 11, 2017 at 6:35 AM, Dongjin Lee <dong...@apache.org>
> > > >> wrote:
> > > >> >
> > > >> > > Hi Ismael,
> > > >> > >
> > > >> > > 1. In the case of compression output, yes, lz4 is producing the
> > > >> smaller
> > > >> > > output than gzip. In fact, my benchmark was inspired
> > > >> > > by MessageCompressionTest#testCompressSize unit test and the
> > result
> > > >> is
> > > >> > > same - 396 bytes for gzip and 387 bytes for lz4.
> > > >> > > 2. I agree that my (former) approach can result in unreliable
> > > output.
> > > >> > > However, I am experiencing difficulties on how to acquire the
> > > >> benchmark
> > > >> > > metrics from Kafka. For you recommended JMH, I just started to
> > > google
> > > >> for
> > > >> > > it. If possible, could you give any example on how to use JMH
> > > against
> > > >> > > Kafka? If it is the case, it will be a great help.
> > > >> > > Regards,Dongjin
> > > >> > >
> > > >> > > _
> > > >> > > From: Ismael Juma <ism...@juma.me.uk>
> > > >> > > Sent: Wednesday, January 11, 2017 7:33 PM
> > > >> > > Subject: Re: [DISCUSS] KIP-110: Add Codec for ZStandard
> > Compression
> > > >> > > To:  <dev@kafka.apache.org>
> > > >> > >
> > > >> > >
> > > >> > > Thanks Dongjin. I highly recommend using JMH for the benchmark,
> > the
> > > >> > > existing one has a few problems that could result in unreliable
> > > >> results.
> > > >> > > Also, it's a bit surprising that LZ4 is producing smaller output
> > > than
> > > >> > gzip.
> > > >> > > Is that right?
> > > >> > >
> > > >> > > Ismael
> > > >> > >
> > > >> > > On Wed, Jan 11, 2017 at 10:20 AM, Dongjin Lee <
> dong...@apache.org
> > >
> > > >> > wrote:
> > > >> > >
> > > >> > > > Ismael,
> > > >> > > >
> > > >> > > > I pushed the benchmark code I used, with some updates
> > (iteration:
> > > >> 20 ->
> > > >> > > > 1000). I also updated the KIP page with the updated benchmark
> > > >> results.
> > > >> > > > Please take a review when you are free. The attached
> screenshot
> > > >> shows
> > > >> > how
> > > >> > > > to run the benchmarker.
> > > >> > > >
> > > >> > > > Thanks,
> > > >> > > > Dongjin
> > > >> > > >
> > > >> > > > On Tue, Jan 10, 2017 at 8:03 PM, Dongjin Lee <
> > dong...@apache.org>
> > > >> > wrote:
> > > >> > > >
> > > >> > > >> Ismael,
> > > >> > > >>
> > > >> > > >> I see. Then, I will share the benchmark code I used by
> > tomorrow.
> > > >> > Thanks
> > > >> > > >> for your guidance.
> > > >> > > >>
> > > >> > > >> Best,
> > > >> > > >> Dongjin
> > > >> > > >>
> > > >> > > >> -
> > > >> > > >>
> > > >> > > >> Dongjin Lee
> > > >> > > >>
> > > >> > > >> Software developer in Line+.
> > > >> > > >> So interested in massive-scale machine learning.
> > > >> > > >>
> > > >> > > >> facebook: www.facebook.com/dongjin.lee.kr
> > > >> > > >> linkedin: kr.linkedin.com/in/dongjinleekr
> > > >> > > >> github: github.com/dongjinleekr
> > > >> > > >> twitter: www.twitter.com/dongjinleekr
> > > >> > > >>
> > > >> > > >>
> > > >&g

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression

[Ismael Juma]

So far the discussion was around the performance characteristics of the new
compression algorithm. Another area that is important and is not covered in
the KIP is the compatibility implications. For example, what happens if a
consumer that doesn't support zstd tries to consume a topic compressed with
it? Or if a broker that doesn't support receives data compressed with it?
If we go through that exercise, then more changes may be required (like
bumping the version of produce/fetch protocols).

Ismael

On Wed, Jan 25, 2017 at 3:22 PM, Ben Stopford <b...@confluent.io> wrote:

> Is there more discussion to be had on this KIP, or should it be taken to a
> vote?
>
> On Mon, Jan 16, 2017 at 6:37 AM Dongjin Lee <dong...@apache.org> wrote:
>
> > I updated KIP-110 with JMH-measured benchmark results. Please have a
> review
> > when you are free. (The overall result is not different yet.)
> >
> > Regards,
> > Dongjin
> >
> > +1. Could anyone assign KAFKA-4514 to me?
> >
> > On Thu, Jan 12, 2017 at 11:39 AM, Dongjin Lee <dong...@apache.org>
> wrote:
> >
> > > Okay, I will have a try.
> > > Thanks Ewen for the guidance!!
> > >
> > > Best,
> > > Dongjin
> > >
> > > On Thu, Jan 12, 2017 at 6:44 AM, Ismael Juma <ism...@juma.me.uk>
> wrote:
> > >
> > >> That's a good point Ewen. Dongjin, you could use the branch that Ewen
> > >> linked for the performance testing. It would also help validate the
> PR.
> > >>
> > >> Ismael
> > >>
> > >> On Wed, Jan 11, 2017 at 9:38 PM, Ewen Cheslack-Postava <
> > e...@confluent.io
> > >> >
> > >> wrote:
> > >>
> > >> > FYI, there's an outstanding patch for getting some JMH benchmarking
> > >> setup:
> > >> > https://github.com/apache/kafka/pull/1712 I haven't found time to
> > >> review
> > >> > it
> > >> > (and don't really know JMH well anyway) but it might be worth
> getting
> > >> that
> > >> > landed so we can use it for this as well.
> > >> >
> > >> > -Ewen
> > >> >
> > >> > On Wed, Jan 11, 2017 at 6:35 AM, Dongjin Lee <dong...@apache.org>
> > >> wrote:
> > >> >
> > >> > > Hi Ismael,
> > >> > >
> > >> > > 1. In the case of compression output, yes, lz4 is producing the
> > >> smaller
> > >> > > output than gzip. In fact, my benchmark was inspired
> > >> > > by MessageCompressionTest#testCompressSize unit test and the
> result
> > >> is
> > >> > > same - 396 bytes for gzip and 387 bytes for lz4.
> > >> > > 2. I agree that my (former) approach can result in unreliable
> > output.
> > >> > > However, I am experiencing difficulties on how to acquire the
> > >> benchmark
> > >> > > metrics from Kafka. For you recommended JMH, I just started to
> > google
> > >> for
> > >> > > it. If possible, could you give any example on how to use JMH
> > against
> > >> > > Kafka? If it is the case, it will be a great help.
> > >> > > Regards,Dongjin
> > >> > >
> > >> > > _
> > >> > > From: Ismael Juma <ism...@juma.me.uk>
> > >> > > Sent: Wednesday, January 11, 2017 7:33 PM
> > >> > > Subject: Re: [DISCUSS] KIP-110: Add Codec for ZStandard
> Compression
> > >> > > To:  <dev@kafka.apache.org>
> > >> > >
> > >> > >
> > >> > > Thanks Dongjin. I highly recommend using JMH for the benchmark,
> the
> > >> > > existing one has a few problems that could result in unreliable
> > >> results.
> > >> > > Also, it's a bit surprising that LZ4 is producing smaller output
> > than
> > >> > gzip.
> > >> > > Is that right?
> > >> > >
> > >> > > Ismael
> > >> > >
> > >> > > On Wed, Jan 11, 2017 at 10:20 AM, Dongjin Lee <dong...@apache.org
> >
> > >> > wrote:
> > >> > >
> > >> > > > Ismael,
> > >> > > >
> > >> > > > I pushed the benchmark code I used, with some updates
> (iteration:
> > >> 20 ->
> > >> > > > 1000). I also updat

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression

[Ben Stopford]

Is there more discussion to be had on this KIP, or should it be taken to a
vote?

On Mon, Jan 16, 2017 at 6:37 AM Dongjin Lee <dong...@apache.org> wrote:

> I updated KIP-110 with JMH-measured benchmark results. Please have a review
> when you are free. (The overall result is not different yet.)
>
> Regards,
> Dongjin
>
> +1. Could anyone assign KAFKA-4514 to me?
>
> On Thu, Jan 12, 2017 at 11:39 AM, Dongjin Lee <dong...@apache.org> wrote:
>
> > Okay, I will have a try.
> > Thanks Ewen for the guidance!!
> >
> > Best,
> > Dongjin
> >
> > On Thu, Jan 12, 2017 at 6:44 AM, Ismael Juma <ism...@juma.me.uk> wrote:
> >
> >> That's a good point Ewen. Dongjin, you could use the branch that Ewen
> >> linked for the performance testing. It would also help validate the PR.
> >>
> >> Ismael
> >>
> >> On Wed, Jan 11, 2017 at 9:38 PM, Ewen Cheslack-Postava <
> e...@confluent.io
> >> >
> >> wrote:
> >>
> >> > FYI, there's an outstanding patch for getting some JMH benchmarking
> >> setup:
> >> > https://github.com/apache/kafka/pull/1712 I haven't found time to
> >> review
> >> > it
> >> > (and don't really know JMH well anyway) but it might be worth getting
> >> that
> >> > landed so we can use it for this as well.
> >> >
> >> > -Ewen
> >> >
> >> > On Wed, Jan 11, 2017 at 6:35 AM, Dongjin Lee <dong...@apache.org>
> >> wrote:
> >> >
> >> > > Hi Ismael,
> >> > >
> >> > > 1. In the case of compression output, yes, lz4 is producing the
> >> smaller
> >> > > output than gzip. In fact, my benchmark was inspired
> >> > > by MessageCompressionTest#testCompressSize unit test and the result
> >> is
> >> > > same - 396 bytes for gzip and 387 bytes for lz4.
> >> > > 2. I agree that my (former) approach can result in unreliable
> output.
> >> > > However, I am experiencing difficulties on how to acquire the
> >> benchmark
> >> > > metrics from Kafka. For you recommended JMH, I just started to
> google
> >> for
> >> > > it. If possible, could you give any example on how to use JMH
> against
> >> > > Kafka? If it is the case, it will be a great help.
> >> > > Regards,Dongjin
> >> > >
> >> > > _
> >> > > From: Ismael Juma <ism...@juma.me.uk>
> >> > > Sent: Wednesday, January 11, 2017 7:33 PM
> >> > > Subject: Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression
> >> > > To:  <dev@kafka.apache.org>
> >> > >
> >> > >
> >> > > Thanks Dongjin. I highly recommend using JMH for the benchmark, the
> >> > > existing one has a few problems that could result in unreliable
> >> results.
> >> > > Also, it's a bit surprising that LZ4 is producing smaller output
> than
> >> > gzip.
> >> > > Is that right?
> >> > >
> >> > > Ismael
> >> > >
> >> > > On Wed, Jan 11, 2017 at 10:20 AM, Dongjin Lee <dong...@apache.org>
> >> > wrote:
> >> > >
> >> > > > Ismael,
> >> > > >
> >> > > > I pushed the benchmark code I used, with some updates (iteration:
> >> 20 ->
> >> > > > 1000). I also updated the KIP page with the updated benchmark
> >> results.
> >> > > > Please take a review when you are free. The attached screenshot
> >> shows
> >> > how
> >> > > > to run the benchmarker.
> >> > > >
> >> > > > Thanks,
> >> > > > Dongjin
> >> > > >
> >> > > > On Tue, Jan 10, 2017 at 8:03 PM, Dongjin Lee <dong...@apache.org>
> >> > wrote:
> >> > > >
> >> > > >> Ismael,
> >> > > >>
> >> > > >> I see. Then, I will share the benchmark code I used by tomorrow.
> >> > Thanks
> >> > > >> for your guidance.
> >> > > >>
> >> > > >> Best,
> >> > > >> Dongjin
> >> > > >>
> >> > > >> -
> >> > > >>
> >> > > >> Dongjin Lee
> >> > > >>
>

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression

[Dongjin Lee]

I updated KIP-110 with JMH-measured benchmark results. Please have a review
when you are free. (The overall result is not different yet.)

Regards,
Dongjin

+1. Could anyone assign KAFKA-4514 to me?

On Thu, Jan 12, 2017 at 11:39 AM, Dongjin Lee <dong...@apache.org> wrote:

> Okay, I will have a try.
> Thanks Ewen for the guidance!!
>
> Best,
> Dongjin
>
> On Thu, Jan 12, 2017 at 6:44 AM, Ismael Juma <ism...@juma.me.uk> wrote:
>
>> That's a good point Ewen. Dongjin, you could use the branch that Ewen
>> linked for the performance testing. It would also help validate the PR.
>>
>> Ismael
>>
>> On Wed, Jan 11, 2017 at 9:38 PM, Ewen Cheslack-Postava <e...@confluent.io
>> >
>> wrote:
>>
>> > FYI, there's an outstanding patch for getting some JMH benchmarking
>> setup:
>> > https://github.com/apache/kafka/pull/1712 I haven't found time to
>> review
>> > it
>> > (and don't really know JMH well anyway) but it might be worth getting
>> that
>> > landed so we can use it for this as well.
>> >
>> > -Ewen
>> >
>> > On Wed, Jan 11, 2017 at 6:35 AM, Dongjin Lee <dong...@apache.org>
>> wrote:
>> >
>> > > Hi Ismael,
>> > >
>> > > 1. In the case of compression output, yes, lz4 is producing the
>> smaller
>> > > output than gzip. In fact, my benchmark was inspired
>> > > by MessageCompressionTest#testCompressSize unit test and the result
>> is
>> > > same - 396 bytes for gzip and 387 bytes for lz4.
>> > > 2. I agree that my (former) approach can result in unreliable output.
>> > > However, I am experiencing difficulties on how to acquire the
>> benchmark
>> > > metrics from Kafka. For you recommended JMH, I just started to google
>> for
>> > > it. If possible, could you give any example on how to use JMH against
>> > > Kafka? If it is the case, it will be a great help.
>> > > Regards,Dongjin
>> > >
>> > > _
>> > > From: Ismael Juma <ism...@juma.me.uk>
>> > > Sent: Wednesday, January 11, 2017 7:33 PM
>> > > Subject: Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression
>> > > To:  <dev@kafka.apache.org>
>> > >
>> > >
>> > > Thanks Dongjin. I highly recommend using JMH for the benchmark, the
>> > > existing one has a few problems that could result in unreliable
>> results.
>> > > Also, it's a bit surprising that LZ4 is producing smaller output than
>> > gzip.
>> > > Is that right?
>> > >
>> > > Ismael
>> > >
>> > > On Wed, Jan 11, 2017 at 10:20 AM, Dongjin Lee <dong...@apache.org>
>> > wrote:
>> > >
>> > > > Ismael,
>> > > >
>> > > > I pushed the benchmark code I used, with some updates (iteration:
>> 20 ->
>> > > > 1000). I also updated the KIP page with the updated benchmark
>> results.
>> > > > Please take a review when you are free. The attached screenshot
>> shows
>> > how
>> > > > to run the benchmarker.
>> > > >
>> > > > Thanks,
>> > > > Dongjin
>> > > >
>> > > > On Tue, Jan 10, 2017 at 8:03 PM, Dongjin Lee <dong...@apache.org>
>> > wrote:
>> > > >
>> > > >> Ismael,
>> > > >>
>> > > >> I see. Then, I will share the benchmark code I used by tomorrow.
>> > Thanks
>> > > >> for your guidance.
>> > > >>
>> > > >> Best,
>> > > >> Dongjin
>> > > >>
>> > > >> -
>> > > >>
>> > > >> Dongjin Lee
>> > > >>
>> > > >> Software developer in Line+.
>> > > >> So interested in massive-scale machine learning.
>> > > >>
>> > > >> facebook: www.facebook.com/dongjin.lee.kr
>> > > >> linkedin: kr.linkedin.com/in/dongjinleekr
>> > > >> github: github.com/dongjinleekr
>> > > >> twitter: www.twitter.com/dongjinleekr
>> > > >>
>> > > >>
>> > > >>
>> > > >>
>> > > >> On Tue, Jan 10, 2017 at 7:24 PM +0900, "Ismael Juma" <
>> > ism...@juma.me.uk
>> > > >
>> >

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression

[Dongjin Lee]

Okay, I will have a try.
Thanks Ewen for the guidance!!

Best,
Dongjin

On Thu, Jan 12, 2017 at 6:44 AM, Ismael Juma <ism...@juma.me.uk> wrote:

> That's a good point Ewen. Dongjin, you could use the branch that Ewen
> linked for the performance testing. It would also help validate the PR.
>
> Ismael
>
> On Wed, Jan 11, 2017 at 9:38 PM, Ewen Cheslack-Postava <e...@confluent.io>
> wrote:
>
> > FYI, there's an outstanding patch for getting some JMH benchmarking
> setup:
> > https://github.com/apache/kafka/pull/1712 I haven't found time to review
> > it
> > (and don't really know JMH well anyway) but it might be worth getting
> that
> > landed so we can use it for this as well.
> >
> > -Ewen
> >
> > On Wed, Jan 11, 2017 at 6:35 AM, Dongjin Lee <dong...@apache.org> wrote:
> >
> > > Hi Ismael,
> > >
> > > 1. In the case of compression output, yes, lz4 is producing the smaller
> > > output than gzip. In fact, my benchmark was inspired
> > > by MessageCompressionTest#testCompressSize unit test and the result is
> > > same - 396 bytes for gzip and 387 bytes for lz4.
> > > 2. I agree that my (former) approach can result in unreliable output.
> > > However, I am experiencing difficulties on how to acquire the benchmark
> > > metrics from Kafka. For you recommended JMH, I just started to google
> for
> > > it. If possible, could you give any example on how to use JMH against
> > > Kafka? If it is the case, it will be a great help.
> > > Regards,Dongjin
> > >
> > > _
> > > From: Ismael Juma <ism...@juma.me.uk>
> > > Sent: Wednesday, January 11, 2017 7:33 PM
> > > Subject: Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression
> > > To:  <dev@kafka.apache.org>
> > >
> > >
> > > Thanks Dongjin. I highly recommend using JMH for the benchmark, the
> > > existing one has a few problems that could result in unreliable
> results.
> > > Also, it's a bit surprising that LZ4 is producing smaller output than
> > gzip.
> > > Is that right?
> > >
> > > Ismael
> > >
> > > On Wed, Jan 11, 2017 at 10:20 AM, Dongjin Lee <dong...@apache.org>
> > wrote:
> > >
> > > > Ismael,
> > > >
> > > > I pushed the benchmark code I used, with some updates (iteration: 20
> ->
> > > > 1000). I also updated the KIP page with the updated benchmark
> results.
> > > > Please take a review when you are free. The attached screenshot shows
> > how
> > > > to run the benchmarker.
> > > >
> > > > Thanks,
> > > > Dongjin
> > > >
> > > > On Tue, Jan 10, 2017 at 8:03 PM, Dongjin Lee <dong...@apache.org>
> > wrote:
> > > >
> > > >> Ismael,
> > > >>
> > > >> I see. Then, I will share the benchmark code I used by tomorrow.
> > Thanks
> > > >> for your guidance.
> > > >>
> > > >> Best,
> > > >> Dongjin
> > > >>
> > > >> -
> > > >>
> > > >> Dongjin Lee
> > > >>
> > > >> Software developer in Line+.
> > > >> So interested in massive-scale machine learning.
> > > >>
> > > >> facebook: www.facebook.com/dongjin.lee.kr
> > > >> linkedin: kr.linkedin.com/in/dongjinleekr
> > > >> github: github.com/dongjinleekr
> > > >> twitter: www.twitter.com/dongjinleekr
> > > >>
> > > >>
> > > >>
> > > >>
> > > >> On Tue, Jan 10, 2017 at 7:24 PM +0900, "Ismael Juma" <
> > ism...@juma.me.uk
> > > >
> > > >> wrote:
> > > >>
> > > >> Dongjin,
> > > >>>
> > > >>> The KIP states:
> > > >>>
> > > >>> "I compared the compressed size and compression time of 3 1kb-sized
> > > >>> messages (3102 bytes in total), with the Draft-implementation of
> > > ZStandard
> > > >>> Compression Codec and all currently available CompressionCodecs.
> All
> > > >>> elapsed times are the average of 20 trials."
> > > >>>
> > > >>> But doesn't give any details of how this was implemented. Is the
> > source
> > > >>> code available somewhere? Micro-benchmarking

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression

[Ismael Juma]

That's a good point Ewen. Dongjin, you could use the branch that Ewen
linked for the performance testing. It would also help validate the PR.

Ismael

On Wed, Jan 11, 2017 at 9:38 PM, Ewen Cheslack-Postava <e...@confluent.io>
wrote:

> FYI, there's an outstanding patch for getting some JMH benchmarking setup:
> https://github.com/apache/kafka/pull/1712 I haven't found time to review
> it
> (and don't really know JMH well anyway) but it might be worth getting that
> landed so we can use it for this as well.
>
> -Ewen
>
> On Wed, Jan 11, 2017 at 6:35 AM, Dongjin Lee <dong...@apache.org> wrote:
>
> > Hi Ismael,
> >
> > 1. In the case of compression output, yes, lz4 is producing the smaller
> > output than gzip. In fact, my benchmark was inspired
> > by MessageCompressionTest#testCompressSize unit test and the result is
> > same - 396 bytes for gzip and 387 bytes for lz4.
> > 2. I agree that my (former) approach can result in unreliable output.
> > However, I am experiencing difficulties on how to acquire the benchmark
> > metrics from Kafka. For you recommended JMH, I just started to google for
> > it. If possible, could you give any example on how to use JMH against
> > Kafka? If it is the case, it will be a great help.
> > Regards,Dongjin
> >
> > _________________
> > From: Ismael Juma <ism...@juma.me.uk>
> > Sent: Wednesday, January 11, 2017 7:33 PM
> > Subject: Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression
> > To:  <dev@kafka.apache.org>
> >
> >
> > Thanks Dongjin. I highly recommend using JMH for the benchmark, the
> > existing one has a few problems that could result in unreliable results.
> > Also, it's a bit surprising that LZ4 is producing smaller output than
> gzip.
> > Is that right?
> >
> > Ismael
> >
> > On Wed, Jan 11, 2017 at 10:20 AM, Dongjin Lee <dong...@apache.org>
> wrote:
> >
> > > Ismael,
> > >
> > > I pushed the benchmark code I used, with some updates (iteration: 20 ->
> > > 1000). I also updated the KIP page with the updated benchmark results.
> > > Please take a review when you are free. The attached screenshot shows
> how
> > > to run the benchmarker.
> > >
> > > Thanks,
> > > Dongjin
> > >
> > > On Tue, Jan 10, 2017 at 8:03 PM, Dongjin Lee <dong...@apache.org>
> wrote:
> > >
> > >> Ismael,
> > >>
> > >> I see. Then, I will share the benchmark code I used by tomorrow.
> Thanks
> > >> for your guidance.
> > >>
> > >> Best,
> > >> Dongjin
> > >>
> > >> -
> > >>
> > >> Dongjin Lee
> > >>
> > >> Software developer in Line+.
> > >> So interested in massive-scale machine learning.
> > >>
> > >> facebook: www.facebook.com/dongjin.lee.kr
> > >> linkedin: kr.linkedin.com/in/dongjinleekr
> > >> github: github.com/dongjinleekr
> > >> twitter: www.twitter.com/dongjinleekr
> > >>
> > >>
> > >>
> > >>
> > >> On Tue, Jan 10, 2017 at 7:24 PM +0900, "Ismael Juma" <
> ism...@juma.me.uk
> > >
> > >> wrote:
> > >>
> > >> Dongjin,
> > >>>
> > >>> The KIP states:
> > >>>
> > >>> "I compared the compressed size and compression time of 3 1kb-sized
> > >>> messages (3102 bytes in total), with the Draft-implementation of
> > ZStandard
> > >>> Compression Codec and all currently available CompressionCodecs. All
> > >>> elapsed times are the average of 20 trials."
> > >>>
> > >>> But doesn't give any details of how this was implemented. Is the
> source
> > >>> code available somewhere? Micro-benchmarking in the JVM is pretty
> > tricky so
> > >>> it needs verification before numbers can be trusted. A performance
> test
> > >>> with kafka-producer-perf-test.sh would be nice to have as well, if
> > possible.
> > >>>
> > >>> Thanks,
> > >>> Ismael
> > >>>
> > >>> On Tue, Jan 10, 2017 at 7:44 AM, Dongjin Lee  wrote:
> > >>>
> > >>> > Ismael,
> > >>> >
> > >>> > 1. Is the benchmark in the KIP page not enough? You mean we need a
> > whole
> > >>> > performance test using kafka-producer-perf-test.

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression

[Ewen Cheslack-Postava]

FYI, there's an outstanding patch for getting some JMH benchmarking setup:
https://github.com/apache/kafka/pull/1712 I haven't found time to review it
(and don't really know JMH well anyway) but it might be worth getting that
landed so we can use it for this as well.

-Ewen

On Wed, Jan 11, 2017 at 6:35 AM, Dongjin Lee <dong...@apache.org> wrote:

> Hi Ismael,
>
> 1. In the case of compression output, yes, lz4 is producing the smaller
> output than gzip. In fact, my benchmark was inspired
> by MessageCompressionTest#testCompressSize unit test and the result is
> same - 396 bytes for gzip and 387 bytes for lz4.
> 2. I agree that my (former) approach can result in unreliable output.
> However, I am experiencing difficulties on how to acquire the benchmark
> metrics from Kafka. For you recommended JMH, I just started to google for
> it. If possible, could you give any example on how to use JMH against
> Kafka? If it is the case, it will be a great help.
> Regards,Dongjin
>
> _
> From: Ismael Juma <ism...@juma.me.uk>
> Sent: Wednesday, January 11, 2017 7:33 PM
> Subject: Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression
> To:  <dev@kafka.apache.org>
>
>
> Thanks Dongjin. I highly recommend using JMH for the benchmark, the
> existing one has a few problems that could result in unreliable results.
> Also, it's a bit surprising that LZ4 is producing smaller output than gzip.
> Is that right?
>
> Ismael
>
> On Wed, Jan 11, 2017 at 10:20 AM, Dongjin Lee <dong...@apache.org> wrote:
>
> > Ismael,
> >
> > I pushed the benchmark code I used, with some updates (iteration: 20 ->
> > 1000). I also updated the KIP page with the updated benchmark results.
> > Please take a review when you are free. The attached screenshot shows how
> > to run the benchmarker.
> >
> > Thanks,
> > Dongjin
> >
> > On Tue, Jan 10, 2017 at 8:03 PM, Dongjin Lee <dong...@apache.org> wrote:
> >
> >> Ismael,
> >>
> >> I see. Then, I will share the benchmark code I used by tomorrow. Thanks
> >> for your guidance.
> >>
> >> Best,
> >> Dongjin
> >>
> >> -
> >>
> >> Dongjin Lee
> >>
> >> Software developer in Line+.
> >> So interested in massive-scale machine learning.
> >>
> >> facebook: www.facebook.com/dongjin.lee.kr
> >> linkedin: kr.linkedin.com/in/dongjinleekr
> >> github: github.com/dongjinleekr
> >> twitter: www.twitter.com/dongjinleekr
> >>
> >>
> >>
> >>
> >> On Tue, Jan 10, 2017 at 7:24 PM +0900, "Ismael Juma" <ism...@juma.me.uk
> >
> >> wrote:
> >>
> >> Dongjin,
> >>>
> >>> The KIP states:
> >>>
> >>> "I compared the compressed size and compression time of 3 1kb-sized
> >>> messages (3102 bytes in total), with the Draft-implementation of
> ZStandard
> >>> Compression Codec and all currently available CompressionCodecs. All
> >>> elapsed times are the average of 20 trials."
> >>>
> >>> But doesn't give any details of how this was implemented. Is the source
> >>> code available somewhere? Micro-benchmarking in the JVM is pretty
> tricky so
> >>> it needs verification before numbers can be trusted. A performance test
> >>> with kafka-producer-perf-test.sh would be nice to have as well, if
> possible.
> >>>
> >>> Thanks,
> >>> Ismael
> >>>
> >>> On Tue, Jan 10, 2017 at 7:44 AM, Dongjin Lee  wrote:
> >>>
> >>> > Ismael,
> >>> >
> >>> > 1. Is the benchmark in the KIP page not enough? You mean we need a
> whole
> >>> > performance test using kafka-producer-perf-test.sh?
> >>> >
> >>> > 2. It seems like no major project is relying on it currently.
> However,
> >>> > after reviewing the code, I concluded that at least this project has
> a good
> >>> > test coverage. And for the problem of upstream tracking - although
> there is
> >>> > no significant update on ZStandard to judge this problem, it seems
> not bad.
> >>> > If required, I can take responsibility of the tracking for this
> library.
> >>> >
> >>> > Thanks,
> >>> > Dongjin
> >>> >
> >>> > On Tue, Jan 10, 2017 at 7:09 AM, Ismael Juma  wrote:
> >>> >
> >>> > > Thanks for p

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression

[Dongjin Lee]

Hi Ismael,

1. In the case of compression output, yes, lz4 is producing the smaller output 
than gzip. In fact, my benchmark was inspired by 
MessageCompressionTest#testCompressSize unit test and the result is same - 396 
bytes for gzip and 387 bytes for lz4.
2. I agree that my (former) approach can result in unreliable output. However, 
I am experiencing difficulties on how to acquire the benchmark metrics from 
Kafka. For you recommended JMH, I just started to google for it. If possible, 
could you give any example on how to use JMH against Kafka? If it is the case, 
it will be a great help.
Regards,Dongjin

_
From: Ismael Juma <ism...@juma.me.uk>
Sent: Wednesday, January 11, 2017 7:33 PM
Subject: Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression
To:  <dev@kafka.apache.org>


Thanks Dongjin. I highly recommend using JMH for the benchmark, the
existing one has a few problems that could result in unreliable results.
Also, it's a bit surprising that LZ4 is producing smaller output than gzip.
Is that right?

Ismael

On Wed, Jan 11, 2017 at 10:20 AM, Dongjin Lee <dong...@apache.org> wrote:

> Ismael,
>
> I pushed the benchmark code I used, with some updates (iteration: 20 ->
> 1000). I also updated the KIP page with the updated benchmark results.
> Please take a review when you are free. The attached screenshot shows how
> to run the benchmarker.
>
> Thanks,
> Dongjin
>
> On Tue, Jan 10, 2017 at 8:03 PM, Dongjin Lee <dong...@apache.org> wrote:
>
>> Ismael,
>>
>> I see. Then, I will share the benchmark code I used by tomorrow. Thanks
>> for your guidance.
>>
>> Best,
>> Dongjin
>>
>> -
>>
>> Dongjin Lee
>>
>> Software developer in Line+.
>> So interested in massive-scale machine learning.
>>
>> facebook: www.facebook.com/dongjin.lee.kr
>> linkedin: kr.linkedin.com/in/dongjinleekr
>> github: github.com/dongjinleekr
>> twitter: www.twitter.com/dongjinleekr
>>
>>
>>
>>
>> On Tue, Jan 10, 2017 at 7:24 PM +0900, "Ismael Juma" <ism...@juma.me.uk>
>> wrote:
>>
>> Dongjin,
>>>
>>> The KIP states:
>>>
>>> "I compared the compressed size and compression time of 3 1kb-sized
>>> messages (3102 bytes in total), with the Draft-implementation of ZStandard
>>> Compression Codec and all currently available CompressionCodecs. All
>>> elapsed times are the average of 20 trials."
>>>
>>> But doesn't give any details of how this was implemented. Is the source
>>> code available somewhere? Micro-benchmarking in the JVM is pretty tricky so
>>> it needs verification before numbers can be trusted. A performance test
>>> with kafka-producer-perf-test.sh would be nice to have as well, if possible.
>>>
>>> Thanks,
>>> Ismael
>>>
>>> On Tue, Jan 10, 2017 at 7:44 AM, Dongjin Lee  wrote:
>>>
>>> > Ismael,
>>> >
>>> > 1. Is the benchmark in the KIP page not enough? You mean we need a whole
>>> > performance test using kafka-producer-perf-test.sh?
>>> >
>>> > 2. It seems like no major project is relying on it currently. However,
>>> > after reviewing the code, I concluded that at least this project has a 
>>> > good
>>> > test coverage. And for the problem of upstream tracking - although there 
>>> > is
>>> > no significant update on ZStandard to judge this problem, it seems not 
>>> > bad.
>>> > If required, I can take responsibility of the tracking for this library.
>>> >
>>> > Thanks,
>>> > Dongjin
>>> >
>>> > On Tue, Jan 10, 2017 at 7:09 AM, Ismael Juma  wrote:
>>> >
>>> > > Thanks for posting the KIP, ZStandard looks like a nice improvement over
>>> > > the existing compression algorithms. A couple of questions:
>>> > >
>>> > > 1. Can you please elaborate on the details of the benchmark?
>>> > > 2. About https://github.com/luben/zstd-jni, can we rely on it? A few
>>> > > things
>>> > > to consider: are there other projects using it, does it have good test
>>> > > coverage, are there performance tests, does it track upstream closely?
>>> > >
>>> > > Thanks,
>>> > > Ismael
>>> > >
>>> > > On Fri, Jan 6, 2017 at 2:40 AM, Dongjin Lee  wrote:
>>> > >
>>> > > > Hi all,
>>> > > >
>>> > > 

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression

[Ismael Juma]

Thanks Dongjin. I highly recommend using JMH for the benchmark, the
existing one has a few problems that could result in unreliable results.
Also, it's a bit surprising that LZ4 is producing smaller output than gzip.
Is that right?

Ismael

On Wed, Jan 11, 2017 at 10:20 AM, Dongjin Lee  wrote:

> Ismael,
>
> I pushed the benchmark code I used, with some updates (iteration: 20 ->
> 1000). I also updated the KIP page with the updated benchmark results.
> Please take a review when you are free. The attached screenshot shows how
> to run the benchmarker.
>
> Thanks,
> Dongjin
>
> On Tue, Jan 10, 2017 at 8:03 PM, Dongjin Lee  wrote:
>
>> Ismael,
>>
>> I see. Then, I will share the benchmark code I used by tomorrow. Thanks
>> for your guidance.
>>
>> Best,
>> Dongjin
>>
>> -
>>
>> Dongjin Lee
>>
>> Software developer in Line+.
>> So interested in massive-scale machine learning.
>>
>> facebook: www.facebook.com/dongjin.lee.kr
>> linkedin: kr.linkedin.com/in/dongjinleekr
>> github: github.com/dongjinleekr
>> twitter: www.twitter.com/dongjinleekr
>>
>>
>>
>>
>> On Tue, Jan 10, 2017 at 7:24 PM +0900, "Ismael Juma" 
>> wrote:
>>
>> Dongjin,
>>>
>>> The KIP states:
>>>
>>> "I compared the compressed size and compression time of 3 1kb-sized
>>> messages (3102 bytes in total), with the Draft-implementation of ZStandard
>>> Compression Codec and all currently available CompressionCodecs. All
>>> elapsed times are the average of 20 trials."
>>>
>>> But doesn't give any details of how this was implemented. Is the source
>>> code available somewhere? Micro-benchmarking in the JVM is pretty tricky so
>>> it needs verification before numbers can be trusted. A performance test
>>> with kafka-producer-perf-test.sh would be nice to have as well, if possible.
>>>
>>> Thanks,
>>> Ismael
>>>
>>> On Tue, Jan 10, 2017 at 7:44 AM, Dongjin Lee  wrote:
>>>
>>> > Ismael,
>>> >
>>> > 1. Is the benchmark in the KIP page not enough? You mean we need a whole
>>> > performance test using kafka-producer-perf-test.sh?
>>> >
>>> > 2. It seems like no major project is relying on it currently. However,
>>> > after reviewing the code, I concluded that at least this project has a 
>>> > good
>>> > test coverage. And for the problem of upstream tracking - although there 
>>> > is
>>> > no significant update on ZStandard to judge this problem, it seems not 
>>> > bad.
>>> > If required, I can take responsibility of the tracking for this library.
>>> >
>>> > Thanks,
>>> > Dongjin
>>> >
>>> > On Tue, Jan 10, 2017 at 7:09 AM, Ismael Juma  wrote:
>>> >
>>> > > Thanks for posting the KIP, ZStandard looks like a nice improvement over
>>> > > the existing compression algorithms. A couple of questions:
>>> > >
>>> > > 1. Can you please elaborate on the details of the benchmark?
>>> > > 2. About https://github.com/luben/zstd-jni, can we rely on it? A few
>>> > > things
>>> > > to consider: are there other projects using it, does it have good test
>>> > > coverage, are there performance tests, does it track upstream closely?
>>> > >
>>> > > Thanks,
>>> > > Ismael
>>> > >
>>> > > On Fri, Jan 6, 2017 at 2:40 AM, Dongjin Lee  wrote:
>>> > >
>>> > > > Hi all,
>>> > > >
>>> > > > I've just posted a new KIP "KIP-110: Add Codec for ZStandard
>>> > Compression"
>>> > > > for
>>> > > > discussion:
>>> > > >
>>> > > > https://cwiki.apache.org/confluence/display/KAFKA/KIP-
>>> > > > 110%3A+Add+Codec+for+ZStandard+Compression
>>> > > >
>>> > > > Please have a look when you are free.
>>> > > >
>>> > > > Best,
>>> > > > Dongjin
>>> > > >
>>> > > > --
>>> > > > *Dongjin Lee*
>>> > > >
>>> > > >
>>> > > > *Software developer in Line+.So interested in massive-scale machine
>>> > > > learning.facebook: www.facebook.com/dongjin.lee.kr
>>> > > > linkedin:
>>> > > > kr.linkedin.com/in/dongjinleekr
>>> > > > github:
>>> > > > github.com/dongjinleekr
>>> > > > twitter: www.twitter.com/dongjinleekr
>>> > > > *
>>> > > >
>>> > >
>>> >
>>> >
>>> >
>>> > --
>>> > *Dongjin Lee*
>>> >
>>> >
>>> > *Software developer in Line+.So interested in massive-scale machine
>>> > learning.facebook: www.facebook.com/dongjin.lee.kr
>>> > linkedin:
>>> > kr.linkedin.com/in/dongjinleekr
>>> > github:
>>> > github.com/dongjinleekr
>>> > twitter: www.twitter.com/dongjinleekr
>>> > *
>>> >
>>>
>>>
>
>
> --
> *Dongjin Lee*
>
>
> *Software developer in Line+.So interested in massive-scale machine
> learning.facebook: www.facebook.com/dongjin.lee.kr
> linkedin: 
> kr.linkedin.com/in/dongjinleekr
> github:
> github.com/dongjinleekr
> twitter: www.twitter.com/dongjinleekr
> *
>

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression

[Dongjin Lee]

Ismael,

I pushed the benchmark code I used, with some updates (iteration: 20 ->
1000). I also updated the KIP page with the updated benchmark results.
Please take a review when you are free. The attached screenshot shows how
to run the benchmarker.

Thanks,
Dongjin

On Tue, Jan 10, 2017 at 8:03 PM, Dongjin Lee  wrote:

> Ismael,
>
> I see. Then, I will share the benchmark code I used by tomorrow. Thanks
> for your guidance.
>
> Best,
> Dongjin
>
> -
>
> Dongjin Lee
>
> Software developer in Line+.
> So interested in massive-scale machine learning.
>
> facebook: www.facebook.com/dongjin.lee.kr
> linkedin: kr.linkedin.com/in/dongjinleekr
> github: github.com/dongjinleekr
> twitter: www.twitter.com/dongjinleekr
>
>
>
>
> On Tue, Jan 10, 2017 at 7:24 PM +0900, "Ismael Juma" 
> wrote:
>
> Dongjin,
>>
>> The KIP states:
>>
>> "I compared the compressed size and compression time of 3 1kb-sized
>> messages (3102 bytes in total), with the Draft-implementation of ZStandard
>> Compression Codec and all currently available CompressionCodecs. All
>> elapsed times are the average of 20 trials."
>>
>> But doesn't give any details of how this was implemented. Is the source
>> code available somewhere? Micro-benchmarking in the JVM is pretty tricky so
>> it needs verification before numbers can be trusted. A performance test
>> with kafka-producer-perf-test.sh would be nice to have as well, if possible.
>>
>> Thanks,
>> Ismael
>>
>> On Tue, Jan 10, 2017 at 7:44 AM, Dongjin Lee  wrote:
>>
>> > Ismael,
>> >
>> > 1. Is the benchmark in the KIP page not enough? You mean we need a whole
>> > performance test using kafka-producer-perf-test.sh?
>> >
>> > 2. It seems like no major project is relying on it currently. However,
>> > after reviewing the code, I concluded that at least this project has a good
>> > test coverage. And for the problem of upstream tracking - although there is
>> > no significant update on ZStandard to judge this problem, it seems not bad.
>> > If required, I can take responsibility of the tracking for this library.
>> >
>> > Thanks,
>> > Dongjin
>> >
>> > On Tue, Jan 10, 2017 at 7:09 AM, Ismael Juma  wrote:
>> >
>> > > Thanks for posting the KIP, ZStandard looks like a nice improvement over
>> > > the existing compression algorithms. A couple of questions:
>> > >
>> > > 1. Can you please elaborate on the details of the benchmark?
>> > > 2. About https://github.com/luben/zstd-jni, can we rely on it? A few
>> > > things
>> > > to consider: are there other projects using it, does it have good test
>> > > coverage, are there performance tests, does it track upstream closely?
>> > >
>> > > Thanks,
>> > > Ismael
>> > >
>> > > On Fri, Jan 6, 2017 at 2:40 AM, Dongjin Lee  wrote:
>> > >
>> > > > Hi all,
>> > > >
>> > > > I've just posted a new KIP "KIP-110: Add Codec for ZStandard
>> > Compression"
>> > > > for
>> > > > discussion:
>> > > >
>> > > > https://cwiki.apache.org/confluence/display/KAFKA/KIP-
>> > > > 110%3A+Add+Codec+for+ZStandard+Compression
>> > > >
>> > > > Please have a look when you are free.
>> > > >
>> > > > Best,
>> > > > Dongjin
>> > > >
>> > > > --
>> > > > *Dongjin Lee*
>> > > >
>> > > >
>> > > > *Software developer in Line+.So interested in massive-scale machine
>> > > > learning.facebook: www.facebook.com/dongjin.lee.kr
>> > > > linkedin:
>> > > > kr.linkedin.com/in/dongjinleekr
>> > > > github:
>> > > > github.com/dongjinleekr
>> > > > twitter: www.twitter.com/dongjinleekr
>> > > > *
>> > > >
>> > >
>> >
>> >
>> >
>> > --
>> > *Dongjin Lee*
>> >
>> >
>> > *Software developer in Line+.So interested in massive-scale machine
>> > learning.facebook: www.facebook.com/dongjin.lee.kr
>> > linkedin:
>> > kr.linkedin.com/in/dongjinleekr
>> > github:
>> > github.com/dongjinleekr
>> > twitter: www.twitter.com/dongjinleekr
>> > *
>> >
>>
>>


-- 
*Dongjin Lee*


*Software developer in Line+.So interested in massive-scale machine
learning.facebook: www.facebook.com/dongjin.lee.kr
linkedin:
kr.linkedin.com/in/dongjinleekr
github:
github.com/dongjinleekr
twitter: www.twitter.com/dongjinleekr
*

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression

[Dongjin Lee]

Ismael,
I see. Then, I will share the benchmark code I used by tomorrow. Thanks for 
your guidance.
Best,Dongjin
-

Dongjin Lee

Software developer in Line+.
So interested in massive-scale machine learning.

facebook: www.facebook.com/dongjin.lee.kr
linkedin: kr.linkedin.com/in/dongjinleekr
github: github.com/dongjinleekr
twitter: www.twitter.com/dongjinleekr




On Tue, Jan 10, 2017 at 7:24 PM +0900, "Ismael Juma"  wrote:










Dongjin,

The KIP states:

"I compared the compressed size and compression time of 3 1kb-sized
messages (3102 bytes in total), with the Draft-implementation of ZStandard
Compression Codec and all currently available CompressionCodecs. All
elapsed times are the average of 20 trials."

But doesn't give any details of how this was implemented. Is the source
code available somewhere? Micro-benchmarking in the JVM is pretty tricky so
it needs verification before numbers can be trusted. A performance test
with kafka-producer-perf-test.sh would be nice to have as well, if possible.

Thanks,
Ismael

On Tue, Jan 10, 2017 at 7:44 AM, Dongjin Lee  wrote:

> Ismael,
>
> 1. Is the benchmark in the KIP page not enough? You mean we need a whole
> performance test using kafka-producer-perf-test.sh?
>
> 2. It seems like no major project is relying on it currently. However,
> after reviewing the code, I concluded that at least this project has a good
> test coverage. And for the problem of upstream tracking - although there is
> no significant update on ZStandard to judge this problem, it seems not bad.
> If required, I can take responsibility of the tracking for this library.
>
> Thanks,
> Dongjin
>
> On Tue, Jan 10, 2017 at 7:09 AM, Ismael Juma  wrote:
>
> > Thanks for posting the KIP, ZStandard looks like a nice improvement over
> > the existing compression algorithms. A couple of questions:
> >
> > 1. Can you please elaborate on the details of the benchmark?
> > 2. About https://github.com/luben/zstd-jni, can we rely on it? A few
> > things
> > to consider: are there other projects using it, does it have good test
> > coverage, are there performance tests, does it track upstream closely?
> >
> > Thanks,
> > Ismael
> >
> > On Fri, Jan 6, 2017 at 2:40 AM, Dongjin Lee  wrote:
> >
> > > Hi all,
> > >
> > > I've just posted a new KIP "KIP-110: Add Codec for ZStandard
> Compression"
> > > for
> > > discussion:
> > >
> > > https://cwiki.apache.org/confluence/display/KAFKA/KIP-
> > > 110%3A+Add+Codec+for+ZStandard+Compression
> > >
> > > Please have a look when you are free.
> > >
> > > Best,
> > > Dongjin
> > >
> > > --
> > > *Dongjin Lee*
> > >
> > >
> > > *Software developer in Line+.So interested in massive-scale machine
> > > learning.facebook: www.facebook.com/dongjin.lee.kr
> > > linkedin:
> > > kr.linkedin.com/in/dongjinleekr
> > > github:
> > > github.com/dongjinleekr
> > > twitter: www.twitter.com/dongjinleekr
> > > *
> > >
> >
>
>
>
> --
> *Dongjin Lee*
>
>
> *Software developer in Line+.So interested in massive-scale machine
> learning.facebook: www.facebook.com/dongjin.lee.kr
> linkedin:
> kr.linkedin.com/in/dongjinleekr
> github:
> github.com/dongjinleekr
> twitter: www.twitter.com/dongjinleekr
> *
>

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression

[Ismael Juma]

Dongjin,

The KIP states:

"I compared the compressed size and compression time of 3 1kb-sized
messages (3102 bytes in total), with the Draft-implementation of ZStandard
Compression Codec and all currently available CompressionCodecs. All
elapsed times are the average of 20 trials."

But doesn't give any details of how this was implemented. Is the source
code available somewhere? Micro-benchmarking in the JVM is pretty tricky so
it needs verification before numbers can be trusted. A performance test
with kafka-producer-perf-test.sh would be nice to have as well, if possible.

Thanks,
Ismael

On Tue, Jan 10, 2017 at 7:44 AM, Dongjin Lee  wrote:

> Ismael,
>
> 1. Is the benchmark in the KIP page not enough? You mean we need a whole
> performance test using kafka-producer-perf-test.sh?
>
> 2. It seems like no major project is relying on it currently. However,
> after reviewing the code, I concluded that at least this project has a good
> test coverage. And for the problem of upstream tracking - although there is
> no significant update on ZStandard to judge this problem, it seems not bad.
> If required, I can take responsibility of the tracking for this library.
>
> Thanks,
> Dongjin
>
> On Tue, Jan 10, 2017 at 7:09 AM, Ismael Juma  wrote:
>
> > Thanks for posting the KIP, ZStandard looks like a nice improvement over
> > the existing compression algorithms. A couple of questions:
> >
> > 1. Can you please elaborate on the details of the benchmark?
> > 2. About https://github.com/luben/zstd-jni, can we rely on it? A few
> > things
> > to consider: are there other projects using it, does it have good test
> > coverage, are there performance tests, does it track upstream closely?
> >
> > Thanks,
> > Ismael
> >
> > On Fri, Jan 6, 2017 at 2:40 AM, Dongjin Lee  wrote:
> >
> > > Hi all,
> > >
> > > I've just posted a new KIP "KIP-110: Add Codec for ZStandard
> Compression"
> > > for
> > > discussion:
> > >
> > > https://cwiki.apache.org/confluence/display/KAFKA/KIP-
> > > 110%3A+Add+Codec+for+ZStandard+Compression
> > >
> > > Please have a look when you are free.
> > >
> > > Best,
> > > Dongjin
> > >
> > > --
> > > *Dongjin Lee*
> > >
> > >
> > > *Software developer in Line+.So interested in massive-scale machine
> > > learning.facebook: www.facebook.com/dongjin.lee.kr
> > > linkedin:
> > > kr.linkedin.com/in/dongjinleekr
> > > github:
> > > github.com/dongjinleekr
> > > twitter: www.twitter.com/dongjinleekr
> > > *
> > >
> >
>
>
>
> --
> *Dongjin Lee*
>
>
> *Software developer in Line+.So interested in massive-scale machine
> learning.facebook: www.facebook.com/dongjin.lee.kr
> linkedin:
> kr.linkedin.com/in/dongjinleekr
> github:
> github.com/dongjinleekr
> twitter: www.twitter.com/dongjinleekr
> *
>

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression

[Dongjin Lee]

Ismael,

1. Is the benchmark in the KIP page not enough? You mean we need a whole
performance test using kafka-producer-perf-test.sh?

2. It seems like no major project is relying on it currently. However,
after reviewing the code, I concluded that at least this project has a good
test coverage. And for the problem of upstream tracking - although there is
no significant update on ZStandard to judge this problem, it seems not bad.
If required, I can take responsibility of the tracking for this library.

Thanks,
Dongjin

On Tue, Jan 10, 2017 at 7:09 AM, Ismael Juma  wrote:

> Thanks for posting the KIP, ZStandard looks like a nice improvement over
> the existing compression algorithms. A couple of questions:
>
> 1. Can you please elaborate on the details of the benchmark?
> 2. About https://github.com/luben/zstd-jni, can we rely on it? A few
> things
> to consider: are there other projects using it, does it have good test
> coverage, are there performance tests, does it track upstream closely?
>
> Thanks,
> Ismael
>
> On Fri, Jan 6, 2017 at 2:40 AM, Dongjin Lee  wrote:
>
> > Hi all,
> >
> > I've just posted a new KIP "KIP-110: Add Codec for ZStandard Compression"
> > for
> > discussion:
> >
> > https://cwiki.apache.org/confluence/display/KAFKA/KIP-
> > 110%3A+Add+Codec+for+ZStandard+Compression
> >
> > Please have a look when you are free.
> >
> > Best,
> > Dongjin
> >
> > --
> > *Dongjin Lee*
> >
> >
> > *Software developer in Line+.So interested in massive-scale machine
> > learning.facebook: www.facebook.com/dongjin.lee.kr
> > linkedin:
> > kr.linkedin.com/in/dongjinleekr
> > github:
> > github.com/dongjinleekr
> > twitter: www.twitter.com/dongjinleekr
> > *
> >
>



-- 
*Dongjin Lee*


*Software developer in Line+.So interested in massive-scale machine
learning.facebook: www.facebook.com/dongjin.lee.kr
linkedin:
kr.linkedin.com/in/dongjinleekr
github:
github.com/dongjinleekr
twitter: www.twitter.com/dongjinleekr
*

Re: [DISCUSS] KIP-110: Add Codec for ZStandard Compression

[Dongjin Lee]

It seems like no one needs any update on this KIP. If then, May I start the
vote?

Regards,
Dongjin

On Fri, Jan 6, 2017 at 11:40 AM, Dongjin Lee  wrote:

> Hi all,
>
> I've just posted a new KIP "KIP-110: Add Codec for ZStandard Compression"
> for
> discussion:
>
> https://cwiki.apache.org/confluence/display/KAFKA/KIP-
> 110%3A+Add+Codec+for+ZStandard+Compression
>
> Please have a look when you are free.
>
> Best,
> Dongjin
>
> --
> *Dongjin Lee*
>
>
> *Software developer in Line+.So interested in massive-scale machine
> learning.facebook: www.facebook.com/dongjin.lee.kr
> linkedin: 
> kr.linkedin.com/in/dongjinleekr
> github:
> github.com/dongjinleekr
> twitter: www.twitter.com/dongjinleekr
> *
>



-- 
*Dongjin Lee*


*Software developer in Line+.So interested in massive-scale machine
learning.facebook: www.facebook.com/dongjin.lee.kr
linkedin:
kr.linkedin.com/in/dongjinleekr
github:
github.com/dongjinleekr
twitter: www.twitter.com/dongjinleekr
*

[DISCUSS] KIP-110: Add Codec for ZStandard Compression

[Dongjin Lee]

Hi all,

I've just posted a new KIP "KIP-110: Add Codec for ZStandard Compression"
for
discussion:

https://cwiki.apache.org/confluence/display/KAFKA/KIP-110%3A+Add+Codec+for+ZStandard+Compression

Please have a look when you are free.

Best,
Dongjin

-- 
*Dongjin Lee*


*Software developer in Line+.So interested in massive-scale machine
learning.facebook: www.facebook.com/dongjin.lee.kr
linkedin:
kr.linkedin.com/in/dongjinleekr
github:
github.com/dongjinleekr
twitter: www.twitter.com/dongjinleekr
*