From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cuda.sgi.com (cuda1.sgi.com [192.48.157.11]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id o749L3Cj026721 for ; Wed, 4 Aug 2010 04:21:03 -0500 Received: from bombadil.infradead.org (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id 97CC514C61D7 for ; Wed, 4 Aug 2010 02:29:26 -0700 (PDT) Received: from bombadil.infradead.org (bombadil.infradead.org [18.85.46.34]) by cuda.sgi.com with ESMTP id DFBoWPufgCtocjbb for ; Wed, 04 Aug 2010 02:29:26 -0700 (PDT) Date: Wed, 4 Aug 2010 05:21:22 -0400 From: Christoph Hellwig Subject: Re: How to track down abysmal performance ata - raid1 - crypto - vg/lv - xfs Message-ID: <20100804092122.GA2998@infradead.org> References: <20100804073546.GA7494@comet.dominikbrodowski.net> <20100804085039.GA11671@infradead.org> <20100804091317.GA27779@isilmar-3.linta.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20100804091317.GA27779@isilmar-3.linta.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: Dominik Brodowski , Christoph Hellwig , linux-raid@vger.kernel.org, xfs@oss.sgi.com, linux-kernel@vger.kernel.org On Wed, Aug 04, 2010 at 11:13:17AM +0200, Dominik Brodowski wrote: > > show these problems? > > No, 2.6.31 to 2.6.34 show similar behaviour. Ok, so it's been around for a while. Can you test the write speed of each individual device layer by doing a large read from it, using: dd if= of=/dev/null bs=8k iflag=direct where device starts with the /dev/sda* device, and goes up to the MD device, the dm-crypt device and the LV. And yes, it's safe to read from the device while it's otherwise mounted/used. _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs