From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail143.messagelabs.com (mail143.messagelabs.com [216.82.254.35]) by kanga.kvack.org (Postfix) with SMTP id 9650D6B0055 for ; Tue, 26 May 2009 22:34:53 -0400 (EDT) Received: from m6.gw.fujitsu.co.jp ([10.0.50.76]) by fgwmail6.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id n4R2ZOvI019898 for (envelope-from kosaki.motohiro@jp.fujitsu.com); Wed, 27 May 2009 11:35:24 +0900 Received: from smail (m6 [127.0.0.1]) by outgoing.m6.gw.fujitsu.co.jp (Postfix) with ESMTP id 27E8C45DE50 for ; Wed, 27 May 2009 11:35:24 +0900 (JST) Received: from s6.gw.fujitsu.co.jp (s6.gw.fujitsu.co.jp [10.0.50.96]) by m6.gw.fujitsu.co.jp (Postfix) with ESMTP id 0C96945DD72 for ; Wed, 27 May 2009 11:35:24 +0900 (JST) Received: from s6.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s6.gw.fujitsu.co.jp (Postfix) with ESMTP id D0BACE38005 for ; Wed, 27 May 2009 11:35:23 +0900 (JST) Received: from ml14.s.css.fujitsu.com (ml14.s.css.fujitsu.com [10.249.87.104]) by s6.gw.fujitsu.co.jp (Postfix) with ESMTP id CC8F8E38002 for ; Wed, 27 May 2009 11:35:22 +0900 (JST) From: KOSAKI Motohiro Subject: Re: [PATCH] readahead:add blk_run_backing_dev In-Reply-To: <6.0.0.20.2.20090527110937.0770c420@172.19.0.2> References: <20090527020909.GB17658@localhost> <6.0.0.20.2.20090527110937.0770c420@172.19.0.2> Message-Id: <20090527113211.6891.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Date: Wed, 27 May 2009 11:35:21 +0900 (JST) Sender: owner-linux-mm@kvack.org To: Hisashi Hifumi Cc: kosaki.motohiro@jp.fujitsu.com, Wu Fengguang , Andrew Morton , "linux-kernel@vger.kernel.org" , "linux-fsdevel@vger.kernel.org" , "linux-mm@kvack.org" , "jens.axboe@oracle.com" List-ID: > >> >even consumed 9% of a CPU, so where on earth has the kernel gone to? > >> > > >> >Have you been able to reproduce this in your testing? > >> > >> Yes, this test on my environment is reproducible. > > > >Hisashi, does your environment have some special configurations? > > Hi. > My testing environment is as follows: > Hardware: HP DL580 > CPU:Xeon 3.2GHz *4 HT enabled > Memory:8GB > Storage: Dothill SANNet2 FC (7Disks RAID-0 Array) > > I did dd to this disk-array and got improved performance number. > > I noticed that when a disk is just one HDD, performance improvement > is very small. thas's odd. Why your patch depend on transfer rate difference? -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org