Re: Queryable State max number of clients

[Ziyad Muhammed]

Hi Aljoscha, Ufuk

Thank you for the replies.

I'm using RocksDB state backend. Could you please explain the blocking I/O
calls mentioned?
when will it happen? And what will be the effect? A timeout exception?


Best
Ziyad

On Mon, Aug 14, 2017 at 10:17 PM, Ufuk Celebi  wrote:

> This is as Aljoscha describes. Each thread can handle many different
> clients at the same time. You shouldn't need to change the defaults in
> most cases.
>
> The network threads handle the TCP connections and dispatch query
> tasks to the query threads which do the actual querying of the state
> backend. In case of the RocksDB backend for example this might involve
> blocking I/O calls.
>
> – Ufuk
>
> On Mon, Aug 14, 2017 at 12:35 PM, Aljoscha Krettek 
> wrote:
> > Hi,
> >
> > I think the number of network treads and number of query threads only
> > roughly correlate with the number of clients that can query in parallel
> > since this is using asynchronous communication via Akka/Netty. Of course,
> > increasing that number means there can be more connections but I think
> even
> > just 1 Thread or each of those should be able to easily handle multiple
> > queries at the same time.
> >
> > I'm cc'ing Ufuk and Kostas who might know more about this.
> >
> > Best,
> > Aljoscha
> >
> > On 9. Aug 2017, at 17:19, Ziyad Muhammed  wrote:
> >
> > Hi all,
> >
> > I'm trying to understand how many parallel clients will be supported by
> the
> > queryable state.
> >
> > query.server.network-threads: number of network (event loop) threads for
> the
> > KvStateServer (0 => #slots)
> > query.server.query-threads: number of asynchronous query threads for the
> > KvStateServerHandler (0 => #slots).
> >
> > so, if I choose 0 for both these parameters, what will be the maximum
> number
> > of parallel clients supported?
> >
> > I tried more parallel clients than number of slots, but all of them were
> > able to query the state in parallel. Can someone help me to understand
> the
> > logic here?
> >
> > Thanks in advance.
> >
> > Best
> > Ziyad
> >
> >
>

Re: Queryable State max number of clients

[Ufuk Celebi]

This is as Aljoscha describes. Each thread can handle many different
clients at the same time. You shouldn't need to change the defaults in
most cases.

The network threads handle the TCP connections and dispatch query
tasks to the query threads which do the actual querying of the state
backend. In case of the RocksDB backend for example this might involve
blocking I/O calls.

– Ufuk

On Mon, Aug 14, 2017 at 12:35 PM, Aljoscha Krettek  wrote:
> Hi,
>
> I think the number of network treads and number of query threads only
> roughly correlate with the number of clients that can query in parallel
> since this is using asynchronous communication via Akka/Netty. Of course,
> increasing that number means there can be more connections but I think even
> just 1 Thread or each of those should be able to easily handle multiple
> queries at the same time.
>
> I'm cc'ing Ufuk and Kostas who might know more about this.
>
> Best,
> Aljoscha
>
> On 9. Aug 2017, at 17:19, Ziyad Muhammed  wrote:
>
> Hi all,
>
> I'm trying to understand how many parallel clients will be supported by the
> queryable state.
>
> query.server.network-threads: number of network (event loop) threads for the
> KvStateServer (0 => #slots)
> query.server.query-threads: number of asynchronous query threads for the
> KvStateServerHandler (0 => #slots).
>
> so, if I choose 0 for both these parameters, what will be the maximum number
> of parallel clients supported?
>
> I tried more parallel clients than number of slots, but all of them were
> able to query the state in parallel. Can someone help me to understand the
> logic here?
>
> Thanks in advance.
>
> Best
> Ziyad
>
>

Re: Queryable State max number of clients

[Aljoscha Krettek]

Hi,

I think the number of network treads and number of query threads only roughly 
correlate with the number of clients that can query in parallel since this is 
using asynchronous communication via Akka/Netty. Of course, increasing that 
number means there can be more connections but I think even just 1 Thread or 
each of those should be able to easily handle multiple queries at the same time.

I'm cc'ing Ufuk and Kostas who might know more about this.

Best,
Aljoscha

> On 9. Aug 2017, at 17:19, Ziyad Muhammed  wrote:
> 
> Hi all,
> 
> I'm trying to understand how many parallel clients will be supported by the 
> queryable state. 
> 
> query.server.network-threads: number of network (event loop) threads for the 
> KvStateServer (0 => #slots)
> query.server.query-threads: number of asynchronous query threads for the 
> KvStateServerHandler (0 => #slots).
> so, if I choose 0 for both these parameters, what will be the maximum number 
> of parallel clients supported?
> 
> I tried more parallel clients than number of slots, but all of them were able 
> to query the state in parallel. Can someone help me to understand the logic 
> here?
> 
> Thanks in advance.
> 
> Best
> Ziyad

Queryable State max number of clients

[Ziyad Muhammed]

Hi all,

I'm trying to understand how many parallel clients will be supported by the
queryable state.


   - query.server.network-threads: number of network (event loop) threads
   for the KvStateServer (0 => #slots)
   - query.server.query-threads: number of asynchronous query threads for
   the KvStateServerHandler (0 => #slots).

so, if I choose 0 for both these parameters, what will be the maximum
number of parallel clients supported?

I tried more parallel clients than number of slots, but all of them were
able to query the state in parallel. Can someone help me to understand the
logic here?

Thanks in advance.

Best
Ziyad