X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (unknown [200.46.204.144]) by svr1.postgresql.org (Postfix) with ESMTP id 1438E52AF8 for ; Mon, 18 Jul 2005 02:43:34 -0300 (ADT) Received: from svr1.postgresql.org ([200.46.204.71]) by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024) with ESMTP id 94280-02 for ; Mon, 18 Jul 2005 05:43:32 +0000 (GMT) Received: from rambo.iniquinet.com (rambo.iniquinet.com [69.39.89.10]) by svr1.postgresql.org (Postfix) with ESMTP id 113ED52AE1 for ; Mon, 18 Jul 2005 02:43:31 -0300 (ADT) Received: (qmail 9280 invoked by uid 1010); 18 Jul 2005 01:43:32 -0400 Received: from Robert_Creager@LogicalChaos.org by rambo.iniquinet.com by uid 1002 with qmail-scanner-1.20 (clamscan: 0.70. spamassassin: 3.0.3. Clear:RC:0(63.147.78.131):SA:0(?/?):. Processed in 1.237431 secs); 18 Jul 2005 05:43:32 -0000 Received: from unknown (HELO thunder.logicalchaos.org) (perl?test@logicalchaos.org@63.147.78.131) by rambo.iniquinet.com with AES256-SHA encrypted SMTP; 18 Jul 2005 01:43:30 -0400 Received: from logicalchaos.org (thunder.logicalchaos.org [192.168.0.250]) by thunder.logicalchaos.org (Postfix) with ESMTP id 64FE4311CE; Sun, 17 Jul 2005 23:43:29 -0600 (MDT) Date: Sun, 17 Jul 2005 23:43:29 -0600 From: Robert Creager To: Tom Lane Cc: "Matthew T. O'Connor" , PGPerformance Subject: Re: Huge performance problem between 7.4.1 and 8.0.3 - CS Message-ID: <20050717234329.05ce2e52@thunder.logicalchaos.org> In-Reply-To: <24616.1121660310@sss.pgh.pa.us> References: <20050717213416.59dcb52e@thunder.logicalchaos.org> <42DB2684.9020706@zeut.net> <20050717221050.7c4ac241@thunder.logicalchaos.org> <24616.1121660310@sss.pgh.pa.us> Organization: Starlight Vision, LLC. X-Mailer: Sylpheed-Claws 1.0.3 (GTK+ 1.2.10; i586-mandrake-linux-gnu) Mime-Version: 1.0 Content-Type: multipart/signed; boundary=Signature_Sun__17_Jul_2005_23_43_29_-0600_z2HHaZ2Lg_vObEHB; protocol="application/pgp-signature"; micalg=pgp-sha1 X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, hits=0.001 tagged_above=0 required=5 tests=AWL X-Spam-Level: X-Archive-Number: 200507/252 X-Sequence-Number: 13493 --Signature_Sun__17_Jul_2005_23_43_29_-0600_z2HHaZ2Lg_vObEHB Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable When grilled further on (Mon, 18 Jul 2005 00:18:30 -0400), Tom Lane confessed: > Robert Creager writes: > > I am, and it is. It's ANALYZING and VACUUM'ing tables every interval (= 5 mi=3D > > nutes > > - 8.0.3). Right now, for that last 4 hours, I'm not VACUUMing the 7.4.1 > > database and it's still clicking along at < .2 second queries. >=20 > Have you compared physical table sizes? If the autovac daemon did let > things get out of hand, you'd need a VACUUM FULL or CLUSTER or TRUNCATE > to get the table size back down --- plain VACUUM is unlikely to fix it. Table sizes, no. Entire DB size is 45Mb for 803 and 29Mb for 741. Cannot = make a direct comparison between the two as I've run against more machines now w= ith 803 than 741, so I'd expect it to be larger. I'm still running relatively clean on 803 with cron vacuum. The CS are jum= ping from 100 to 120k, but it's not steady state like it was before, and queries= are all under 5 seconds (none hitting the logs) and are typically (glancing at = test runs) still under 1 sec, with some hitting ~2 seconds occasionally. I've 6 runs going concurrently. Just saw (vmstat 1) a set of 8 seconds whe= re the CS didn't drop below 90k, but right now its at ~300 for over 30 seconds= ...=20 It's bouncing all over the place, but staying reasonably well behaved overa= ll. Whoop. Spoke too soon. Just hit the wall. CS at ~80k constant, queries o= ver 10 seconds and rising (30+ now)... Looking at ps, the vacuum is currently running. Going back in the logs, the CS and vacuum hit at about the same t= ime. I'm going to go back to 741 with the same load and see what happens by tomo= rrow morning... I'll change the cron vac to hit the 741 db. Cheers, Rob --=20 23:29:24 up 4 days, 3:04, 6 users, load average: 0.02, 0.07, 0.08 Linux 2.6.5-02 #8 SMP Mon Jul 12 21:34:44 MDT 2004 --Signature_Sun__17_Jul_2005_23_43_29_-0600_z2HHaZ2Lg_vObEHB Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.4 (GNU/Linux) iEYEARECAAYFAkLbQYEACgkQLQ/DKuwDYzn8MgCfSWOcbx4kPIaeGUaDpA5t8nF3 newAn3/EzLgp9ysUXGL8S4/CUWKDDCvw =znj8 -----END PGP SIGNATURE----- --Signature_Sun__17_Jul_2005_23_43_29_-0600_z2HHaZ2Lg_vObEHB--