[pgpool-general: 3961] Re: accept() scalability issues

[Pablo Sanchez]

[ Comments below, in-line ]


On 08/13/2015 09:18 AM, Michael Renner wrote:
>
>> On 10 Aug 2015, at 11:25, Tatsuo Ishii <ishii at postgresql.org> wrote:
>>
>> [ trimmed ]
>>
>> Ok, here is the experimental patch to serialize select(2) for
>> listen fds by using semaphore. Could you please try it out?  The
>> patch is against 3.3-stable.
>
>
> Thank you very much, that worked fine!
>
> In a synthetic test with 1000 children and ~30 connections per
> second this lowered the amount of context switches from ~38.000/sec to
> ~1.000/sec.
>

Hey Michael,

Do you have any /sar -u 3 XXX/ data showing CPU usage between /before/
and /after/?

Thx!
--
Pablo Sanchez - Blueoak Database Engineering, Inc
Ph:    819.459.1926         Blog:  http://pablo-blog.blueoakdb.com
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