Received: from localhost (maia-1.hub.org [200.46.204.191]) by postgresql.org (Postfix) with ESMTP id 4C3CD9FBF54 for ; Fri, 13 Jul 2007 09:45:13 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.191]) (amavisd-maia, port 10024) with ESMTP id 87840-09 for ; Fri, 13 Jul 2007 09:45:05 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey-1.7.5 Received: from vms042pub.verizon.net (vms042pub.verizon.net [206.46.252.42]) by postgresql.org (Postfix) with ESMTP id D88EE9FBAF1 for ; Fri, 13 Jul 2007 09:45:05 -0300 (ADT) Received: from osgiliath.mathom.us ([72.66.0.221]) by vms042.mailsrvcs.net (Sun Java System Messaging Server 6.2-6.01 (built Apr 3 2006)) with ESMTPA id <0JL4007D9BEJF5M8@vms042.mailsrvcs.net> for pgsql-performance@postgresql.org; Fri, 13 Jul 2007 07:44:43 -0500 (CDT) Received: from localhost (localhost [127.0.0.1]) by osgiliath.mathom.us (Postfix) with ESMTP id 17B351F816; Fri, 13 Jul 2007 08:44:40 -0400 (EDT) Received: from osgiliath.mathom.us ([127.0.0.1]) by localhost (osgiliath.home.mathom.us [127.0.0.1]) (amavisd-new, port 10024) with LMTP id G+T97l5ugy1y; Fri, 13 Jul 2007 08:44:38 -0400 (EDT) Received: by osgiliath.mathom.us (Postfix, from userid 1000) id 7EEF61F80E; Fri, 13 Jul 2007 08:44:38 -0400 (EDT) Date: Fri, 13 Jul 2007 08:44:38 -0400 From: Michael Stone Subject: Re: TRUNCATE TABLE In-reply-to: <46972DFA.9000900@microbizz.nl> To: Adriaan van Os Cc: pgsql-performance@postgresql.org Mail-followup-to: Adriaan van Os , pgsql-performance@postgresql.org Message-id: <20070713124435.GL31358@mathom.us> MIME-version: 1.0 Content-type: text/plain; charset=us-ascii; format=flowed Content-disposition: inline X-Virus-Scanned: Debian amavisd-new at mathom.us X-Pgp-Fingerprint: 53 FF 38 00 E7 DD 0A 9C 84 52 84 C5 EE DF 7C 88 References: <46953949.3030201@microbizz.nl> <87ps2ypox3.fsf@oxford.xeocode.com> <46972DFA.9000900@microbizz.nl> User-Agent: Mutt/1.5.13 (2006-08-11) X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200707/152 X-Sequence-Number: 25836 On Fri, Jul 13, 2007 at 09:47:06AM +0200, Adriaan van Os wrote: >That's a remarkable advice, because XFS is known to be slow at creating and >deleting files, see and >. xfs' slowness is proportional to the *number* rather than the *size* of the files. In postgres you'll tend to have fewer, larger, files than you would in (e.g.) a source code repository, so it is generally more important to have a filesystem that deletes large files quickly than a filesystem that deletes lots of files quickly. I'd suspect that the same is true for mythtv. Mike Stone