Received: from localhost (maia-3.hub.org [200.46.204.184]) by postgresql.org (Postfix) with ESMTP id 443EB9FA344 for ; Tue, 2 Jan 2007 13:30:34 -0400 (AST) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.184]) (amavisd-new, port 10024) with ESMTP id 39134-07 for ; Tue, 2 Jan 2007 13:30:25 -0400 (AST) X-Greylist: from auto-whitelisted by SQLgrey-1.7.4 Received: from sss.pgh.pa.us (sss.pgh.pa.us [66.207.139.130]) by postgresql.org (Postfix) with ESMTP id BF6509FA334 for ; Tue, 2 Jan 2007 13:30:25 -0400 (AST) Received: from sss2.sss.pgh.pa.us (tgl@localhost [127.0.0.1]) by sss.pgh.pa.us (8.13.6/8.13.6) with ESMTP id l02HUOSl005877; Tue, 2 Jan 2007 12:30:24 -0500 (EST) To: Erik Jones cc: pgsql-performance@postgresql.org Subject: Re: Slow dump? In-reply-to: <459A8B51.8000906@myemma.com> References: <459A8B51.8000906@myemma.com> Comments: In-reply-to Erik Jones message dated "Tue, 02 Jan 2007 10:41:53 -0600" Date: Tue, 02 Jan 2007 12:30:24 -0500 Message-ID: <5876.1167759024@sss.pgh.pa.us> From: Tom Lane X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200701/20 X-Sequence-Number: 22621 Erik Jones writes: > Hello, we recently migrated our system from 8.1.x to 8.2 and when > running dumps have noticed an extreme decrease in speed where the dump > is concerned (by more than a factor of 2). That's odd. pg_dump is normally pretty much I/O bound, at least assuming your tables are sizable. The only way it wouldn't be is if you have a datatype with a very slow output converter. Have you looked into exactly which tables are slow to dump and what datatypes they contain? (Running pg_dump with log_min_duration_statement enabled would provide useful data about which steps take a long time, if you're not sure.) regards, tom lane