From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ronald Moesbergen Subject: Re: [RESEND] [PATCH] readahead:add blk_run_backing_dev Date: Mon, 29 Jun 2009 16:56:18 +0200 Message-ID: References: <20090620035504.GA19516@localhost> <20090629093423.GB1315@localhost> <4A489DAC.7000007@vlnb.net> <20090629125434.GA8416@localhost> <4A48BBF9.6050408@vlnb.net> <20090629131326.GA23668@localhost> <20090629132841.GA26171@localhost> <20090629145147.GA29433@localhost> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Vladislav Bolkhovitin , 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 To: Wu Fengguang Return-path: Received: from mail-ew0-f210.google.com ([209.85.219.210]:40940 "EHLO mail-ew0-f210.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752821AbZF2O4Q (ORCPT ); Mon, 29 Jun 2009 10:56:16 -0400 In-Reply-To: <20090629145147.GA29433@localhost> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: 2009/6/29 Wu Fengguang : > 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! You're welcome. >> 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"? These: http://scst.svn.sourceforge.net/viewvc/scst/trunk/scst/kernel/ Regards, Ronald.