Received: from maia.hub.org (maia-2.hub.org [200.46.204.251]) by mail.postgresql.org (Postfix) with ESMTP id CEA8363367E for ; Fri, 4 Jun 2010 11:25:42 -0300 (ADT) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.204.251]) (amavisd-maia, port 10024) with ESMTP id 80077-03 for ; Fri, 4 Jun 2010 14:25:32 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from sss.pgh.pa.us (sss.pgh.pa.us [66.207.139.130]) by mail.postgresql.org (Postfix) with ESMTP id 03FD76330F6 for ; Fri, 4 Jun 2010 11:25:33 -0300 (ADT) Received: from sss2.sss.pgh.pa.us (tgl@localhost [127.0.0.1]) by sss.pgh.pa.us (8.14.2/8.14.2) with ESMTP id o54EPU3F002504; Fri, 4 Jun 2010 10:25:30 -0400 (EDT) To: Andres Freund cc: pgsql-performance@postgresql.org, Jon Schewe Subject: Re: How filesystems matter with PostgreSQL In-reply-to: <201006041504.03218.andres@anarazel.de> References: <4C08EEDF.7090403@mtu.net> <201006041504.03218.andres@anarazel.de> Comments: In-reply-to Andres Freund message dated "Fri, 04 Jun 2010 15:04:02 +0200" Date: Fri, 04 Jun 2010 10:25:30 -0400 Message-ID: <2503.1275661530@sss.pgh.pa.us> From: Tom Lane X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=-0.011 tagged_above=-10 required=5 tests=BAYES_40=-0.001, T_RP_MATCHES_RCVD=-0.01 X-Spam-Level: X-Archive-Number: 201006/83 X-Sequence-Number: 38939 Andres Freund writes: > On Friday 04 June 2010 14:17:35 Jon Schewe wrote: >> XFS (logbufs=8): ~4 hours to finish >> ext4: ~1 hour 50 minutes to finish >> ext3: 15 minutes to finish >> ext3 on LVM: 15 minutes to finish > My guess is that some of the difference comes from barrier differences. ext4 > uses barriers by default, ext3 does not. Or, to put it more clearly: the reason ext3 is fast is that it's unsafe. regards, tom lane