From: Scott Marlowe <smarlowe@g2switchworks.com>
To: Jérôme BENOIS <benois@argia-engineering.fr>
Cc: Guillaume Smet <guillaume.smet@gmail.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: High CPU Load
Date: Thu, 14 Sep 2006 09:17:24 -0500
Message-ID: <1158243444.24726.10.camel@state.g2switchworks.com> (raw)
In-Reply-To: <1158242414.5226.31.camel@localhost.localdomain>
References: <1158239339.5226.17.camel@localhost.localdomain>
<1d4e0c10609140646g6ad1ab4w51dec49afba11fd7@mail.gmail.com>
<1158242414.5226.31.camel@localhost.localdomain>
On Thu, 2006-09-14 at 09:00, Jérôme BENOIS wrote:
> Hi Guillaume,
>
> Le jeudi 14 septembre 2006 à 15:46 +0200, Guillaume Smet a écrit :
> > On 9/14/06, Jérôme BENOIS <benois@argia-engineering.fr> wrote:
> > > I migrated Postgres server from 7.4.6 to 8.1.4, But my server is
> > > completely full, by moment load average > 40
> > > All queries analyzed by EXPLAIN, all indexes are used .. IO is good ...
> >
> > What is the bottleneck? Are you CPU bound? Do you have iowait? Do you
> > swap? Any weird things in vmstat output?
> the load average goes up and goes down between 1 and 70, it's strange.
> IO wait and swap are good. I have just very high CPU load. And it's user
> land time.
>
> top output :
>
> top - 15:57:57 up 118 days, 9:04, 4 users, load average: 8.16, 9.16,
> 15.51
> Tasks: 439 total, 7 running, 432 sleeping, 0 stopped, 0 zombie
> Cpu(s): 87.3% us, 6.8% sy, 0.0% ni, 4.8% id, 0.1% wa, 0.2% hi,
> 0.8% si
> Mem: 2076404k total, 2067812k used, 8592k free, 13304k buffers
> Swap: 1954312k total, 236k used, 1954076k free, 1190296k cached
>
> PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
> 15667 postgres 25 0 536m 222m 532m R 98.8 11.0 1:39.29 postmaster
> 19533 postgres 25 0 535m 169m 532m R 92.9 8.3 0:38.68 postmaster
> 16278 postgres 25 0 537m 285m 532m R 86.3 14.1 1:37.56 postmaster
> 18695 postgres 16 0 535m 171m 532m S 16.1 8.5 0:14.46 postmaster
> 18092 postgres 16 0 544m 195m 532m R 11.5 9.7 0:31.87 postmaster
> 16896 postgres 15 0 534m 215m 532m S 6.3 10.6 0:27.13 postmaster
Somewhere, the query planner is likely making a really bad decision.
Have you analyzed your dbs?
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-performance@postgresql.org
Cc: smarlowe@g2switchworks.com, benois@argia-engineering.fr, guillaume.smet@gmail.com
Subject: Re: High CPU Load
In-Reply-To: <1158243444.24726.10.camel@state.g2switchworks.com>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox