Re: Quantum Flow Engineering Newsletter #18

[David Durst]

While we're pushing forward on Quantum Flow things, there are a lot of
people looking to help out where they can.

To make this at least a little organized, please remember to assign a bug
to yourself if you're working on it (or planning to).
https://charts.mozilla.org/quantum/blockers.html# is showing a few
unassigned that are actually assigned (judging from the comments).

Similarly, if something IS assigned to you, but it's not actively being
worked on and you're OK with someone else doing so, please un-assign
yourself.

Thanks...


--
David Durst [:ddurst]

On Tue, Aug 8, 2017 at 9:26 AM, Mike Conley  wrote:

> Mike Conley ported scrollbox to use smooth scrolling instead of JS driven
>> scrolling .  This
>> affects most importantly scrolling the tab bar, and should make it more
>> smooth by removing a lot of slow code that used to run and off-loading that
>> work to the compositor through CSS-based smooth scrolling!  He notes
>>  on the bug
>> that in order to achieve great performance some follow-ups may be needed.
>
>
> Just to ensure credit is given where it's due - that was 95% Dão
> Gottwald's work. I just helped push the last 5% over the line when he got
> focused on getting square tabs landed. Thanks Dão!
>
> On 4 August 2017 at 04:04, Ehsan Akhgari  wrote:
>
>> Hi everyone,
>>
>> This has been a busy week.  A lot of fixes have landed, setting up the
>> Firefox 57 cycle for a good start.  On the platform side, a notable change
>> that will be in the upcoming Nightly is the fix for document.cookie using
>> synchronous IPC.  This super popular API call slows down various web pages
>> today in Firefox, and starting from tomorrow, the affected pages should
>> experience a great speedup.  I have sometimes seen the slowdown caused by
>> this one issue to amount to a second or more in some situations, thanks a
>> lot to Amy and Josh for their hard work on this feature.  The readers of
>> these newsletters know that the work on fixing this issue has gone on for a
>> long time, and it's great to see it land early in the cycle.
>>
>> On the front-end side, more and more of the UI changes of Photon are
>> landing in Nightly.  One of the overall changes that I have seen is that
>> the interface is starting to feel a lot more responsive and snappy than it
>> was around this time last year.  This is due to many different details.  A
>> lot of work has gone into fixing rough edges in the performance of the
>> existing code, some of which I have covered but most of which is under the 
>> Photon
>> Performance project
>> .  Also the new UI
>> is built with performance in mind, so for example where animations are
>> used, they use the compositor and don't run on the main thread.  All of the
>> pieces of this performance puzzle are nicely coming to fit in together, and
>> it is great to see that this hard work is paying off.
>>
>> On the Speedometer front, things are progressing with fast pace.  We have
>> been fixing issues that have been on our list from the previous findings,
>> which has somewhat slowed down the pace of finding new issues to work on.
>> Although the SpiderMonkey team haven't waited around
>>  and are
>> continually finding new optimization opportunities out of further
>> investigations.  There is still more work to be done there!
>>
>> I will now move own to acknowledge the great work of all of those who
>> helped make Firefox faster last week.  I hope I am not mistakenly
>> forgetting any names here!
>>
>>- Andrew McCreight got rid of some cycle collector overhead
>> related to
>>using QueryInterface to canonicalize the nsISupports pointers stored in 
>> the
>>purple buffer, and similarly for pointers encountered during
>>traversal of native roots
>> as well.
>>- Kris Maglione added some utilities to BrowserUtils
>> that should
>>help our front-end devs avoid synchronous layout and style flushes.
>>- Amy Chung got rid of the sync IPC messages in the cookie service
>>! This was a
>>substantial amount of work and should eliminate jank on a number of sites
>>that get and set cookies frequently.
>>- Jessica Jong made us check a boolean flag instead of doing a linear
>>search looking for an attribute in order to determine whether an Element 
>> is
>>required .
>>- André Bargull made String.prototype.toLower/UpperCase use direct VM
>>calls, and also added specialized unicode::CanLower/UpperCase 

Re: Quantum Flow Engineering Newsletter #18

[Mike Conley]

>
> Mike Conley ported scrollbox to use smooth scrolling instead of JS driven
> scrolling .  This
> affects most importantly scrolling the tab bar, and should make it more
> smooth by removing a lot of slow code that used to run and off-loading that
> work to the compositor through CSS-based smooth scrolling!  He notes
>  on the bug
> that in order to achieve great performance some follow-ups may be needed.


Just to ensure credit is given where it's due - that was 95% Dão Gottwald's
work. I just helped push the last 5% over the line when he got focused on
getting square tabs landed. Thanks Dão!

On 4 August 2017 at 04:04, Ehsan Akhgari  wrote:

> Hi everyone,
>
> This has been a busy week.  A lot of fixes have landed, setting up the
> Firefox 57 cycle for a good start.  On the platform side, a notable change
> that will be in the upcoming Nightly is the fix for document.cookie using
> synchronous IPC.  This super popular API call slows down various web pages
> today in Firefox, and starting from tomorrow, the affected pages should
> experience a great speedup.  I have sometimes seen the slowdown caused by
> this one issue to amount to a second or more in some situations, thanks a
> lot to Amy and Josh for their hard work on this feature.  The readers of
> these newsletters know that the work on fixing this issue has gone on for a
> long time, and it's great to see it land early in the cycle.
>
> On the front-end side, more and more of the UI changes of Photon are
> landing in Nightly.  One of the overall changes that I have seen is that
> the interface is starting to feel a lot more responsive and snappy than it
> was around this time last year.  This is due to many different details.  A
> lot of work has gone into fixing rough edges in the performance of the
> existing code, some of which I have covered but most of which is under the 
> Photon
> Performance project .
> Also the new UI is built with performance in mind, so for example where
> animations are used, they use the compositor and don't run on the main
> thread.  All of the pieces of this performance puzzle are nicely coming to
> fit in together, and it is great to see that this hard work is paying off.
>
> On the Speedometer front, things are progressing with fast pace.  We have
> been fixing issues that have been on our list from the previous findings,
> which has somewhat slowed down the pace of finding new issues to work on.
> Although the SpiderMonkey team haven't waited around
>  and are
> continually finding new optimization opportunities out of further
> investigations.  There is still more work to be done there!
>
> I will now move own to acknowledge the great work of all of those who
> helped make Firefox faster last week.  I hope I am not mistakenly
> forgetting any names here!
>
>- Andrew McCreight got rid of some cycle collector overhead
> related to
>using QueryInterface to canonicalize the nsISupports pointers stored in the
>purple buffer, and similarly for pointers encountered during traversal
>of native roots 
>as well.
>- Kris Maglione added some utilities to BrowserUtils
> that should
>help our front-end devs avoid synchronous layout and style flushes.
>- Amy Chung got rid of the sync IPC messages in the cookie service
>! This was a
>substantial amount of work and should eliminate jank on a number of sites
>that get and set cookies frequently.
>- Jessica Jong made us check a boolean flag instead of doing a linear
>search looking for an attribute in order to determine whether an Element is
>required .
>- André Bargull made String.prototype.toLower/UpperCase use direct VM
>calls, and also added specialized unicode::CanLower/UpperCase overloads for
>Latin1 characters
>.  He also added
>an Ion-inline path for Reflect.getPrototypeOf()
>.  Additionally,
>he made it possible to inline UnsafeGetReservedSlot when the object is
>typed as MIRType::Value
>.  Last but not
>least, he inlined ToObject when called with MIRType::Value
>.
>- Mike Conley ported scrollbox to use smooth scrolling instead of JS
>driven scrolling .
>This affects most 

Quantum Flow Engineering Newsletter #18

[Ehsan Akhgari]

Hi everyone,

This has been a busy week.  A lot of fixes have landed, setting up the
Firefox 57 cycle for a good start.  On the platform side, a notable change
that will be in the upcoming Nightly is the fix for document.cookie using
synchronous IPC.  This super popular API call slows down various web pages
today in Firefox, and starting from tomorrow, the affected pages should
experience a great speedup.  I have sometimes seen the slowdown caused by
this one issue to amount to a second or more in some situations, thanks a
lot to Amy and Josh for their hard work on this feature.  The readers of
these newsletters know that the work on fixing this issue has gone on for a
long time, and it's great to see it land early in the cycle.

On the front-end side, more and more of the UI changes of Photon are
landing in Nightly.  One of the overall changes that I have seen is that
the interface is starting to feel a lot more responsive and snappy than it
was around this time last year.  This is due to many different details.  A
lot of work has gone into fixing rough edges in the performance of the
existing code, some of which I have covered but most of which is under
the Photon
Performance project .
Also the new UI is built with performance in mind, so for example where
animations are used, they use the compositor and don't run on the main
thread.  All of the pieces of this performance puzzle are nicely coming to
fit in together, and it is great to see that this hard work is paying off.

On the Speedometer front, things are progressing with fast pace.  We have
been fixing issues that have been on our list from the previous findings,
which has somewhat slowed down the pace of finding new issues to work on.
Although the SpiderMonkey team haven't waited around
 and are continually
finding new optimization opportunities out of further investigations.
There is still more work to be done there!

I will now move own to acknowledge the great work of all of those who
helped make Firefox faster last week.  I hope I am not mistakenly
forgetting any names here!

   - Andrew McCreight got rid of some cycle collector overhead
    related to using
   QueryInterface to canonicalize the nsISupports pointers stored in the
   purple buffer, and similarly for pointers encountered during traversal
   of native roots 
   as well.
   - Kris Maglione added some utilities to BrowserUtils
    that should help
   our front-end devs avoid synchronous layout and style flushes.
   - Amy Chung got rid of the sync IPC messages in the cookie service
   ! This was a
   substantial amount of work and should eliminate jank on a number of sites
   that get and set cookies frequently.
   - Jessica Jong made us check a boolean flag instead of doing a linear
   search looking for an attribute in order to determine whether an Element is
   required .
   - André Bargull made String.prototype.toLower/UpperCase use direct VM
   calls, and also added specialized unicode::CanLower/UpperCase overloads for
   Latin1 characters .
   He also added an Ion-inline path for Reflect.getPrototypeOf()
   .  Additionally,
   he made it possible to inline UnsafeGetReservedSlot when the object is
   typed as MIRType::Value
   .  Last but not
   least, he inlined ToObject when called with MIRType::Value
   .
   - Mike Conley ported scrollbox to use smooth scrolling instead of JS
   driven scrolling .
   This affects most importantly scrolling the tab bar, and should make it
   more smooth by removing a lot of slow code that used to run and off-loading
   that work to the compositor through CSS-based smooth scrolling!  He notes
    on the bug
   that in order to achieve great performance some follow-ups may be needed.
   - Olli Pettay avoided allocating element state objects needlessly when
   saving the state of  and  elements
   .
   - Tim Taubert and Michael Layzell collaborated on reducing the cost of
   the FormDataListener event handler
    inside
   sessionstore.
   - C.J. Ku fine tuned nsDisplaySVGText::Paint() in several ways
   .
   - Tom Schuster optimized String.prototype.indexOf/lastIndexOf for the
   case where