From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759064AbYEUScY (ORCPT ); Wed, 21 May 2008 14:32:24 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751360AbYEUScN (ORCPT ); Wed, 21 May 2008 14:32:13 -0400 Received: from www.church-of-our-saviour.ORG ([69.25.196.31]:50563 "EHLO thunker.thunk.org" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751199AbYEUScM (ORCPT ); Wed, 21 May 2008 14:32:12 -0400 Date: Wed, 21 May 2008 14:29:49 -0400 From: Theodore Tso To: Andrew Morton Cc: Pavel Machek , Chris Mason , Eric Sandeen , Andi Kleen , linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: Re: [PATCH 0/4] (RESEND) ext3[34] barrier changes Message-ID: <20080521182949.GL8581@mit.edu> Mail-Followup-To: Theodore Tso , Andrew Morton , Pavel Machek , Chris Mason , Eric Sandeen , Andi Kleen , linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org References: <482DDA56.6000301@redhat.com> <20080518211140.b29bee30.akpm@linux-foundation.org> <200805191316.27551.chris.mason@oracle.com> <200805191439.36577.chris.mason@oracle.com> <20080521112224.GD5028@ucw.cz> <20080521110324.668048e0.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080521110324.668048e0.akpm@linux-foundation.org> User-Agent: Mutt/1.5.15+20070412 (2007-04-11) X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: tytso@mit.edu X-SA-Exim-Scanned: No (on thunker.thunk.org); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, May 21, 2008 at 11:03:24AM -0700, Andrew Morton wrote: > > afaik there is no need to enable this feature if the machine (actually > the disks) are on a UPS, yes? Yes, as long as you're confident that there won't be a kernel bug/regression causing a lockup while the server is under severe memory pressure while doing lots of fsync's, file creations, renames, etc. And as long as your 100% confident that UPS's will never fail, janitors will never accidentally hit the Emergency Power Office switch, and so on. - Ted