Re: How to ENABLE SQL capturing???

From: "Joshua D(dot) Drake" <jd(at)commandprompt(dot)com>
To: Gregory Stark <stark(at)enterprisedb(dot)com>
Cc: Jonathan Ellis <jonathan(at)utahpython(dot)org>, smiley2211 <smiley2211(at)yahoo(dot)com>, pgsql-performance(at)postgresql(dot)org
Subject: Re: How to ENABLE SQL capturing???
Date: 2007-08-13 16:15:35
Message-ID: 46C083A7.6000408@commandprompt.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-performance

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Gregory Stark wrote:
> "Joshua D. Drake" <jd(at)commandprompt(dot)com> writes:
>
>> If I recall correctly, it is because syslog is blocking.
>
> Are you sure it isn't just that syslog fsyncs its log files after every log
> message?

Nope I am not sure at all ;). Darcy actually found the issue and can
speak better to it, I never use syslog and have always logged direct to
file.

I don't think the individual syslogs are synchronous but if syslog
> falls behind the buffer will fill and throttle the sender.
>
> If your Postgres data is on the same device as the syslogs those fsyncs will
> probably cause a big slowdown directly on Postgres's I/O as well.
>
> You can turn off the fsyncs in syslog by putting a - before the filename.
>

- --

=== The PostgreSQL Company: Command Prompt, Inc. ===
Sales/Support: +1.503.667.4564 24x7/Emergency: +1.800.492.2240
PostgreSQL solutions since 1997 http://www.commandprompt.com/
UNIQUE NOT NULL
Donate to the PostgreSQL Project: http://www.postgresql.org/about/donate
PostgreSQL Replication: http://www.commandprompt.com/products/

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.6 (GNU/Linux)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

iD8DBQFGwIOnATb/zqfZUUQRAqWqAKCEhoW/01Hc//cDEpREit8ipn2SZwCfUxPE
1Ir6eyuD4EcShwsn4sMAeKA=
=W2cJ
-----END PGP SIGNATURE-----

In response to

Browse pgsql-performance by date

  From Date Subject
Next Message Kevin Grittner 2007-08-13 16:25:01 Re: Help optimize view
Previous Message Gregory Stark 2007-08-13 16:02:41 Re: How to ENABLE SQL capturing???