Received: from localhost (maia-1.hub.org [200.46.204.191]) by postgresql.org (Postfix) with ESMTP id A0B929F957C for ; Mon, 13 Aug 2007 13:13:08 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.191]) (amavisd-maia, port 10024) with ESMTP id 50305-09 for ; Mon, 13 Aug 2007 13:13:01 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey-1.7.5 Received: from lists.commandprompt.com (host-254.commandprompt.net [207.173.203.254]) by postgresql.org (Postfix) with ESMTP id C45879F95AA for ; Mon, 13 Aug 2007 13:13:00 -0300 (ADT) Received: from [192.168.1.50] (or-67-76-146-141.sta.embarqhsd.net [67.76.146.141]) (authenticated bits=0) by lists.commandprompt.com (8.13.7/8.13.6) with ESMTP id l7DGD00V000833 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Mon, 13 Aug 2007 09:13:00 -0700 Message-ID: <46C083A7.6000408@commandprompt.com> Date: Mon, 13 Aug 2007 09:15:35 -0700 From: "Joshua D. Drake" User-Agent: Thunderbird 1.5.0.12 (X11/20070604) MIME-Version: 1.0 To: Gregory Stark CC: Jonathan Ellis , smiley2211 , pgsql-performance@postgresql.org Subject: Re: How to ENABLE SQL capturing??? References: <12060736.post@talk.nabble.com> <20070808203612.GA26143@uio.no> <12096180.post@talk.nabble.com> <12099590.post@talk.nabble.com> <46BCDDAA.3060703@commandprompt.com> <46C07BFA.8000500@commandprompt.com> <87vebjqv6m.fsf@oxford.xeocode.com> In-Reply-To: <87vebjqv6m.fsf@oxford.xeocode.com> X-Enigmail-Version: 0.94.2.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Virus-Scanned: ClamAV 0.91.1/3944/Sun Aug 12 23:12:09 2007 on projects.commandprompt.com X-Virus-Status: Clean X-Greylist: Sender succeded SMTP AUTH authentication, not delayed by milter-greylist-1.6 (lists.commandprompt.com [192.168.2.159]); Mon, 13 Aug 2007 09:13:01 -0700 (PDT) X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200708/131 X-Sequence-Number: 26261 -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Gregory Stark wrote: > "Joshua D. Drake" 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-----