From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cuda.sgi.com (cuda3.sgi.com [192.48.176.15]) by oss.sgi.com (8.12.11.20060308/8.12.11/SuSE Linux 0.7) with ESMTP id mAQMnrQB017274 for ; Wed, 26 Nov 2008 16:49:53 -0600 Received: from ipmail05.adl2.internode.on.net (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id 4A4CA160748C for ; Wed, 26 Nov 2008 14:49:51 -0800 (PST) Received: from ipmail05.adl2.internode.on.net (ipmail05.adl2.internode.on.net [203.16.214.145]) by cuda.sgi.com with ESMTP id mAIArUAoW5ooU9lH for ; Wed, 26 Nov 2008 14:49:51 -0800 (PST) Date: Thu, 27 Nov 2008 08:43:08 +1100 From: Dave Chinner Subject: Re: Extreme slowness with xfs [WAS: Re: Slowness with new pc] Message-ID: <20081126214308.GJ6291@disturbed> References: <1226760254.5089.11.camel@chevrolet> <492B5684.2080107@sandeen.net> <1227647010.7992.34.camel@chevrolet> <200811261330.27328.Martin@lichtvoll.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <200811261330.27328.Martin@lichtvoll.de> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: xfs-bounces@oss.sgi.com Errors-To: xfs-bounces@oss.sgi.com To: Martin Steigerwald Cc: xfs@oss.sgi.com On Wed, Nov 26, 2008 at 01:30:26PM +0100, Martin Steigerwald wrote: > I wonder whether XFS performance with barriers enabled can be improved? Not really. It requires fundamentally altering the way the transaction system works, and that's no easy task. I have a few things that I'm looking at, but nothing that would be considered short-term.... > And whether XFS with disabled write cache (via hdparm) but without > barriers might even be *faster* than XFS with barriers... One thing to > test eventually. Yes, it often is with SATA drives - it depends on the quality of the NCQ implementation in the drive. For SCSI drives, no write cache or barriers is almost always faster than using WC+barriers. Cheers, Dave. -- Dave Chinner david@fromorbit.com _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs