Received: from maia.hub.org (unknown [200.46.208.211]) by mail.postgresql.org (Postfix) with ESMTP id 0D807634A22 for ; Fri, 26 Feb 2010 02:29:45 -0400 (AST) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.208.211]) (amavisd-maia, port 10024) with ESMTP id 23280-07 for ; Fri, 26 Feb 2010 06:29:32 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from mail.erwied.eu (mail.erwied.eu [85.214.80.157]) by mail.postgresql.org (Postfix) with ESMTP id 5F27A63221A for ; Fri, 26 Feb 2010 02:29:34 -0400 (AST) Received: from dslb-094-220-117-154.pools.arcor-ip.net ([94.220.117.154] helo=erwied.dns2go.com ident=mail) by mail.erwied.eu with esmtpsa (Exim 4.71#1) id 1Nkthb-00056B-D9 ; Fri, 26 Feb 2010 07:29:31 +0100 Received: from joe-lifebook.dhcp.erwied.de ([172.17.10.70] helo=localhost) by erwied.dns2go.com with esmtpsa (Exim 4.71#1) id 1NkthZ-0003uG-9a ; Fri, 26 Feb 2010 07:29:29 +0100 Date: Fri, 26 Feb 2010 07:29:22 +0100 From: Jochen Erwied Organization: Creative Chaos Computing X-Priority: 3 (Normal) Message-ID: <1418021012.20100226072922@erwied.eu> To: Tory M Blue CC: pgsql-performance@postgresql.org Subject: Re: bgwriter, checkpoints, curious (seeing delays) In-Reply-To: <8a547c841002252220o4579ead0vd35a44726fdd5c5f@mail.gmail.com> References: <8a547c841002252212t382cfeb4pde3e668a9d3f2f10@mail.gmail.com> <8a547c841002252220o4579ead0vd35a44726fdd5c5f@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable X-Antivirus: avast! (VPS 100225-0, 25.02.2010), Outbound message X-Antivirus-Status: Clean X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=0.001 tagged_above=-10 required=5 tests=BAYES_50=0.001 X-Spam-Level: X-Archive-Number: 201002/366 X-Sequence-Number: 37787 Friday, February 26, 2010, 7:20:38 AM you wrote: > "checkpoint_completion_target (floating point) > interesting that it's a .5 second default setting and I'm seeing > exactly that .5 second delay. =20 It's not an exact time, but a multiplier to 'checkpoint_timeout'. So a setting of .5 with a timeout of 300 seconds means a checkpoint should be completed after 300*0.5 =3D 150 seconds. --=20 Jochen Erwied | home: jochen@erwied.eu +49-208-38800-18, FAX: -19 Sauerbruchstr. 17 | work: joe@mbs-software.de +49-2151-7294-24, FAX: -50 D-45470 Muelheim | mobile: jochen.erwied@vodafone.de +49-173-5404164