From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: with ECARTIS (v1.0.0; list xfs); Fri, 22 Sep 2006 04:51:23 -0700 (PDT) Received: from cuda.sgi.com (cuda1.sgi.com [192.48.168.28]) by oss.sgi.com (8.12.10/8.12.10/SuSE Linux 0.7) with ESMTP id k8MBpDaG019667 for ; Fri, 22 Sep 2006 04:51:14 -0700 Received: from mail.moloch.sk (chrocht.moloch.sk [62.176.169.44]) by cuda.sgi.com (Spam Firewall) with ESMTP id 003C645BF10 for ; Fri, 22 Sep 2006 03:44:38 -0700 (PDT) Received: from dezo.moloch.sk (dezo.moloch.sk [62.176.172.4]) by mail.moloch.sk (Postfix) with ESMTP id 979B6340F14D for ; Fri, 22 Sep 2006 12:44:18 +0200 (CEST) Date: Fri, 22 Sep 2006 12:44:17 +0200 From: Martin Lucina Subject: Write barrier support with LVM2/md Message-ID: <20060922104417.GA4161@dezo.moloch.sk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: xfs-bounce@oss.sgi.com Errors-to: xfs-bounce@oss.sgi.com List-Id: xfs To: xfs@oss.sgi.com Hello, Having recently upgraded several systems to Linux 2.6.16/2.6.18 I learnt about the issues with modern drives and write caching. Thanks for the excellent FAQ entry on this. Unfortunately it seems that write barriers do not work when using XFS on top of LVM2 (device-mapper). Trying an explicit mount with -o barrier gives: Filesystem "dm-4": Disabling barriers, not supported by the underlying device Is anyone working on a fix for this? It might be a good idea to add to the FAQ that write barriers are not supported on dm devices. -mato