From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760163AbZF2Ph6 (ORCPT ); Mon, 29 Jun 2009 11:37:58 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751489AbZF2Phs (ORCPT ); Mon, 29 Jun 2009 11:37:48 -0400 Received: from moutng.kundenserver.de ([212.227.126.171]:59642 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750731AbZF2Phr (ORCPT ); Mon, 29 Jun 2009 11:37:47 -0400 Message-ID: <4A48DFBA.1070608@vlnb.net> Date: Mon, 29 Jun 2009 19:37:30 +0400 From: Vladislav Bolkhovitin User-Agent: Thunderbird 2.0.0.21 (X11/20090320) MIME-Version: 1.0 To: Wu Fengguang CC: Ronald Moesbergen , Andrew Morton , "kosaki.motohiro@jp.fujitsu.com" , "Alan.Brunelle@hp.com" , "hifumi.hisashi@oss.ntt.co.jp" , "linux-kernel@vger.kernel.org" , "linux-fsdevel@vger.kernel.org" , "jens.axboe@oracle.com" , "randy.dunlap@oracle.com" , Bart Van Assche Subject: Re: [RESEND] [PATCH] readahead:add blk_run_backing_dev References: <20090620035504.GA19516@localhost> <4A3CD62B.1020407@vlnb.net> <20090629093423.GB1315@localhost> <4A489DAC.7000007@vlnb.net> <20090629125434.GA8416@localhost> <4A48BBF9.6050408@vlnb.net> <20090629131326.GA23668@localhost> <20090629132841.GA26171@localhost> <20090629145147.GA29433@localhost> In-Reply-To: <20090629145147.GA29433@localhost> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-Provags-ID: V01U2FsdGVkX1+7n3baWUljOPcNKlmBSAC7vyLVEym9/dtcKxD 3Hol8xMhSHEh+mX8J1XBosacq3As00APP6vFheaZ2cEdIXhsK8 uoDuS7kiNMl7eCKpJGXig== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Wu Fengguang, on 06/29/2009 06:51 PM wrote: > On Mon, Jun 29, 2009 at 10:43:48PM +0800, Ronald Moesbergen wrote: >> 2009/6/29 Wu Fengguang : >>> On Mon, Jun 29, 2009 at 09:13:27PM +0800, Wu Fengguang wrote: >>>> On Mon, Jun 29, 2009 at 09:04:57PM +0800, Vladislav Bolkhovitin wrote: >>>>> Wu Fengguang, on 06/29/2009 04:54 PM wrote: >>>>>> Why not 2.6.30? :) >>>>> We started with 2.6.29, so why not complete with it (to save additional >>>>> Ronald's effort to move on 2.6.30)? >>>> OK, that's fair enough. >>> btw, I backported the 2.6.31 context readahead patches to 2.6.29, just >>> in case it will help the SCST performance. >>> >>> Ronald, if you run context readahead, please make sure that the server >>> side readahead size is bigger than the client side readahead size. >> I tried this patch on a vanilla kernel and no other patches applied, >> but it does not seem to help. The iSCSI throughput does not go above >> 60MB/s. (1GB in 17 seconds). I have tried several readahead settings >> from 128KB up to 4MB and kept the server readahead at twice the client >> readahead, but it never comes above 60MB/s. This is using SCST on the > > OK, thanks for the tests anyway! > >> serverside and openiscsi on the client. I get much better throughput >> (90 MB/s) when using the patches supplied with SCST, together with the > > What do you mean by "patches supplied with SCST"? Ronald means io_context patch (http://scst.svn.sourceforge.net/viewvc/scst/trunk/scst/kernel/io_context-2.6.29.patch?revision=717), which allows SCST's I/O threads to share a single IO context. Vlad