Re: WIP/PoC for parallel backup

On Wed, Apr 29, 2020 at 6:11 PM Suraj Kharage
<suraj(dot)kharage(at)enterprisedb(dot)com> wrote:
>
> Hi,
>
> We at EnterpriseDB did some performance testing around this parallel backup to check how this is beneficial and below are the results. In this testing, we run the backup -
> 1) Without Asif’s patch
> 2) With Asif’s patch and combination of workers 1,2,4,8.
>
> We run those test on two setup
>
> 1) Client and Server both on the same machine (Local backups)
>
> 2) Client and server on a different machine (remote backups)
>
>
> Machine details:
>
> 1: Server (on which local backups performed and used as server for remote backups)
>
> 2: Client (Used as a client for remote backups)
>
>
...
>
>
> Client & Server on the same machine, the result shows around 50% improvement in parallel run with worker 4 and 8. We don’t see the huge performance improvement with more workers been added.
>
>
> Whereas, when the client and server on a different machine, we don’t see any major benefit in performance. This testing result matches the testing results posted by David Zhang up thread.
>
>
>
> We ran the test for 100GB backup with parallel worker 4 to see the CPU usage and other information. What we noticed is that server is consuming the CPU almost 100% whole the time and pg_stat_activity shows that server is busy with ClientWrite most of the time.
>
>

Was this for a setup where the client and server were on the same
machine or where the client was on a different machine? If it was for
the case where both are on the same machine, then ideally, we should
see ClientRead events in a similar proportion?

--
With Regards,
Amit Kapila.
EnterpriseDB: http://www.enterprisedb.com