Received: from localhost (unknown [200.46.204.183]) by postgresql.org (Postfix) with ESMTP id EB1BE37BE27 for ; Fri, 3 Oct 2008 05:47:49 -0300 (ADT) Received: from postgresql.org ([200.46.204.86]) by localhost (mx1.hub.org [200.46.204.183]) (amavisd-maia, port 10024) with ESMTP id 14510-02 for ; Fri, 3 Oct 2008 05:47:42 -0300 (ADT) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from fk-out-0910.google.com (fk-out-0910.google.com [209.85.128.186]) by postgresql.org (Postfix) with ESMTP id E8D6D37BD8E for ; Fri, 3 Oct 2008 05:47:41 -0300 (ADT) Received: by fk-out-0910.google.com with SMTP id e30so1177143fke.3 for ; Fri, 03 Oct 2008 01:47:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:subject :cc:in-reply-to:mime-version:content-type:content-transfer-encoding :content-disposition:references; bh=pa6zDhHiQNbXfM9ONyqWUhY7zhxeVoxEp9502/iJtHE=; b=x5JXv5aJXV5HZ1YvWhP/NLpoitVE7QVlmTs97rMPP6fU24JntqHQGMd5jDfyBLNgY2 r3vz2f7LEe4rhWRtwECtpBnnWizQ/6pMyQuf8sn6t82ZxekrlSHIxQocbivDkL7uZ3IM yjKiu8hUH9tFuEgXdWX07KR6n8j+6D9WRgxW4= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:subject:cc:in-reply-to:mime-version :content-type:content-transfer-encoding:content-disposition :references; b=djPLgYLIAtJ1yqxsKuHabjnqQty2I+uoYgWm1Y2PTZ2/DuUEDsuBY+w4RknK8jLc49 LWUWZZ/6DWvlN3y7JZc5IQsOZUbIh8EqW6j658PttM6vOyqgTo20975s+DoC+MaVacbq rZ1sr4lxuFtjMAljf6BqL7Vi3XK+T77iT8dJw= Received: by 10.103.6.6 with SMTP id j6mr446310mui.89.1223023658234; Fri, 03 Oct 2008 01:47:38 -0700 (PDT) Received: by 10.103.213.6 with HTTP; Fri, 3 Oct 2008 01:47:38 -0700 (PDT) Message-ID: Date: Fri, 3 Oct 2008 09:47:38 +0100 From: "Peter Childs" Subject: Re: Slow Inserts on large tables Cc: "Postgresql Performance" In-Reply-To: <48E5D62D.7060400@gmx.net> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <48E5D62D.7060400@gmx.net> X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=1.581 tagged_above=0 required=5 tests=MISSING_HEADERS=1.581 X-Spam-Level: * X-Archive-Number: 200810/22 X-Sequence-Number: 31603 2008/10/3 Peter Eisentraut : > Peter Childs wrote: >> >> I have a problem where by an insert on a "large" table will sometimes >> take longer than usual. > >> I think the problem might have something to do with checkpoints, > > Then show us your checkpointing-related parameters. Or try to set them to a > lot higher values so checkpoints happen more rarely and see if that makes a > difference. > > More often or less often? I've currently got them set to checkpoint_segments = 3 checkpoint_timeout = 180s checkpoint_completion_target = 0.5 after reading that doing more smaller checkpoints might make each checkpoint work quicker and hence less of a performance hit when they actually happen. Regards Peter