| From: | Dmitriy Sarafannikov <d(dot)sarafannikov(at)bk(dot)ru> |
|---|---|
| To: | andres <andres(at)anarazel(dot)de> |
| Cc: | root(at)simply(dot)name, pgsql-performance(at)postgresql(dot)org, PostgreSQL-development <pgsql-hackers(at)postgresql(dot)org> |
| Subject: | Re: [HACKERS] [PERFORM] 9.4 -> 9.5 regression with queries through pgbouncer on RHEL 6 |
| Date: | 2016-07-15 09:24:21 |
| Message-ID: | 1468574661.605279425@f427.i.mail.ru |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers pgsql-performance |
>I don't really see anything suspicious in the profile. This looks more
>like a kernel scheduler issue than a postgres bottleneck one. It seems
>that somehow using nonblocking IO (started in 9.5) causes scheduling
>issues when pgbouncer is also local.
>
>Could you do perf stat -ddd -a sleep 10 or something during both runs? I
>suspect that the context switch ratios will be quite different.
Perf show that in 9.5 case context switches occurs about 2 times less.
Perf output is attached.
Regards,
Dmitriy Sarafannikov
| Attachment | Content-Type | Size |
|---|---|---|
| perf.stat | application/octet-stream | 5.8 KB |
| From | Date | Subject | |
|---|---|---|---|
| Next Message | AMatveev | 2016-07-15 09:29:27 | Re: One process per session lack of sharing |
| Previous Message | Andreas 'ads' Scherbaum | 2016-07-15 08:49:35 | Re: sslmode=require fallback |
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Jan Wieck | 2016-07-17 01:14:50 | Re: slony rpm help slony1-95-2.2.2-1.rhel6.x86_64 |
| Previous Message | Andres Freund | 2016-07-14 18:53:38 | Re: [PERFORM] 9.4 -> 9.5 regression with queries through pgbouncer on RHEL 6 |