Received: from localhost (unknown [200.46.204.183]) by mail.postgresql.org (Postfix) with ESMTP id A484464FDDF for ; Tue, 25 Nov 2008 09:37:01 -0400 (AST) Received: from mail.postgresql.org ([200.46.204.86]) by localhost (mx1.hub.org [200.46.204.183]) (amavisd-maia, port 10024) with ESMTP id 45678-05 for ; Tue, 25 Nov 2008 09:36:59 -0400 (AST) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from sss.pgh.pa.us (sss.pgh.pa.us [66.207.139.130]) by mail.postgresql.org (Postfix) with ESMTP id EDA9764FDBF for ; Tue, 25 Nov 2008 09:36:58 -0400 (AST) Received: from sss2.sss.pgh.pa.us (tgl@localhost [127.0.0.1]) by sss.pgh.pa.us (8.14.2/8.14.2) with ESMTP id mAPDal1h014977; Tue, 25 Nov 2008 08:36:47 -0500 (EST) To: vegard.bones@met.no cc: pgsql-performance@postgresql.org Subject: Re: Deteriorating performance when loading large objects In-reply-to: <63696.85.166.86.82.1227617663.squirrel@webmailsunny.oslo.dnmi.no> References: <63696.85.166.86.82.1227617663.squirrel@webmailsunny.oslo.dnmi.no> Comments: In-reply-to "=?iso-8859-1?Q?Vegard_B=F8nes?=" message dated "Tue, 25 Nov 2008 12:54:23 +0000" Date: Tue, 25 Nov 2008 08:36:46 -0500 Message-ID: <14976.1227620206@sss.pgh.pa.us> From: Tom Lane X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=0 tagged_above=0 required=5 tests=none X-Spam-Level: X-Archive-Number: 200811/255 X-Sequence-Number: 31986 "=?iso-8859-1?Q?Vegard_B=F8nes?=" writes: > I have a problem with large objects in postgresql 8.1: The performance of > loading large objects into a database goes way down after a few days of > operation. > I have a cron job kicking in twice a day, which generates and loads around > 6000 large objects of 3.7MB each. Each night, old data is deleted, so > there is never more than 24000 large object in the database. Are you sure you're deleting the large objects themselves (ie, lo_unlink), and not just deleting some references to them? A manual "vacuum verbose" on pg_largeobject might be informative. regards, tom lane