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 BB18852A01 for ; Sun, 17 Jul 2005 14:08:43 -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 30619-04 for ; Sun, 17 Jul 2005 17:08:36 +0000 (GMT) Received: from wproxy.gmail.com (wproxy.gmail.com [64.233.184.198]) by svr1.postgresql.org (Postfix) with ESMTP id F2759529AE for ; Sun, 17 Jul 2005 14:08:34 -0300 (ADT) Received: by wproxy.gmail.com with SMTP id i20so896329wra for ; Sun, 17 Jul 2005 10:08:34 -0700 (PDT) DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:reply-to:to:subject:mime-version:content-type:content-transfer-encoding:content-disposition; b=npB0MedYWEN3MZti1i8wYb+RpUXj7rV2X3itk7CErwulQ3FcXOWCcapGJer/zfxQgV7v9A/CjjR3xGeLoOrziVzDLxU1r+4vN+kdHSlcDceg3b3EJws3cu/fHikb1UrRBm5cUf82o+ibwlnd62p4YE+lUt7TpaXLi54jdpdFqps= Received: by 10.54.32.52 with SMTP id f52mr126241wrf; Sun, 17 Jul 2005 10:08:34 -0700 (PDT) Received: by 10.54.120.11 with HTTP; Sun, 17 Jul 2005 10:08:34 -0700 (PDT) Message-ID: <59d991c4050717100874c08a86@mail.gmail.com> Date: Sun, 17 Jul 2005 13:08:34 -0400 From: Christopher Petrilli Reply-To: Christopher Petrilli To: pgsql-performance@postgresql.org Subject: Impact of checkpoint_segments under continual load conditions Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, hits=0.128 tagged_above=0 required=5 tests=AWL, RCVD_BY_IP X-Spam-Level: X-Archive-Number: 200507/238 X-Sequence-Number: 13479 I have a unique scenerio. My DB is under "continual load", meaning that I am constantly using COPY to insert new data into the DB. There is no "quiet period" for the database, at least not for hours on end.=20 Normally, checkpoint_segments can help absorb some of that, but my experience is that if I crank the number up, it simply delays the impact, and when it occurs, it takes a VERY long time (minutes) to clear. Thoughts? Chris --=20 | Christopher Petrilli | petrilli@gmail.com