Received: from localhost (unknown [200.46.204.183]) by postgresql.org (Postfix) with ESMTP id 1392B64FFC4 for ; Thu, 28 Aug 2008 10:54:01 -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 62594-10 for ; Thu, 28 Aug 2008 10:53:51 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from mx00.pub.collaborativefusion.com (mx00.pub.collaborativefusion.com [206.210.89.199]) by postgresql.org (Postfix) with ESMTP id DCC3564FD22 for ; Thu, 28 Aug 2008 10:53:56 -0300 (ADT) Received: from vanquish.ws.pitbpa0.priv.collaborativefusion.com (vanquish.ws.pitbpa0.priv.collaborativefusion.com [192.168.2.162]) (SSL: TLSv1/SSLv3,256bits,AES256-SHA) by wingspan with esmtp; Thu, 28 Aug 2008 09:53:54 -0400 id 0005644B.0000000048B6ADF2.00011C42 Date: Thu, 28 Aug 2008 09:53:25 -0400 From: Bill Moran To: Matthew Wakeling Cc: pgsql-performance@postgresql.org Subject: Re: select on 22 GB table causes "An I/O error occured while sending to the backend." exception Message-Id: <20080828095325.3c95f867.wmoran@collaborativefusion.com> In-Reply-To: References: <82bpze3ou8.fsf@mid.bfk.de> Organization: Collaborative Fusion X-Mailer: Sylpheed 2.5.0 (GTK+ 2.12.11; i386-portbld-freebsd7.0) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit 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: 200808/370 X-Sequence-Number: 31251 In response to Matthew Wakeling : > > Probably the best solution is to just tell the kernel somehow to never > kill the postmaster. This thread interested me enough to research this a bit. In linux, it's possible to tell the OOM killer never to consider certain processes for the axe, using /proc magic. See this page: http://linux-mm.org/OOM_Killer Perhaps this should be in the PostgreSQL docs somewhere? -- Bill Moran Collaborative Fusion Inc. http://people.collaborativefusion.com/~wmoran/ wmoran@collaborativefusion.com Phone: 412-422-3463x4023