Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933605Ab0HEPkn (ORCPT ); Thu, 5 Aug 2010 11:40:43 -0400 Received: from rcsinet10.oracle.com ([148.87.113.121]:40151 "EHLO rcsinet10.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753427Ab0HEPkk (ORCPT ); Thu, 5 Aug 2010 11:40:40 -0400 Date: Thu, 5 Aug 2010 11:39:43 -0400 From: Chris Mason To: Dominik Brodowski , josef@redhat.com, Valdis.Kletnieks@vt.edu, Michael Monnerie , Christoph Hellwig , linux-raid@vger.kernel.org, xfs@oss.sgi.com, linux-kernel@vger.kernel.org, dm-devel@redhat.com Subject: Re: direct-io regression [Was: How to track down abysmal performance ata - raid1 - crypto - vg/lv - xfs] Message-ID: <20100805153943.GO29846@think> Mail-Followup-To: Chris Mason , Dominik Brodowski , josef@redhat.com, Valdis.Kletnieks@vt.edu, Michael Monnerie , Christoph Hellwig , linux-raid@vger.kernel.org, xfs@oss.sgi.com, linux-kernel@vger.kernel.org, dm-devel@redhat.com References: <20100805123649.GA18672@dhcp231-156.rdu.redhat.com> <20100805113240.GA29846@think> <20100805153519.GA7242@comet.dominikbrodowski.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20100805153519.GA7242@comet.dominikbrodowski.net> User-Agent: Mutt/1.5.20 (2009-06-14) X-Source-IP: acsmt353.oracle.com [141.146.40.153] X-Auth-Type: Internal IP X-CT-RefId: str=0001.0A090201.4C5ADB55.007B:SCFMA4539814,ss=1,fgs=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 967 Lines: 26 On Thu, Aug 05, 2010 at 05:35:19PM +0200, Dominik Brodowski wrote: > Hey, > > On Thu, Aug 05, 2010 at 07:32:40AM -0400, Chris Mason wrote: > > But, I'm surprised your drive is doing 8K dio reads at 16MB/s, that > > seems a little high. > > Well, that's what it does: > > # $ dd if=/dev/mapper/vg0-home_crypt of=/dev/zero iflag=direct bs=8k count=131072 seek=131072 > # 131072+0 records in > # 131072+0 records out > # 1073741824 bytes (1.1 GB) copied, 62.0177 s, 17.3 MB/s Can I ask you to do the test directly to the real honest to goodness drive? If it were an SSD I'd be less surprised, but then the extra submits shouldn't hurt the ssd that much either. Thanks for testing the patch, I'll send it in. -chris -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/