From: Martin Knoblauch Subject: Re: regression: 100% io-wait with 2.6.24-rcX Date: Wed, 23 Jan 2008 03:12:39 -0800 (PST) Message-ID: <739290.84170.qm@web32614.mail.mud.yahoo.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Linus Torvalds , Mel Gorman , Fengguang Wu , Mike Snitzer , Peter Zijlstra , jplatte@naasa.net, Ingo Molnar , linux-kernel@vger.kernel.org, "linux-ext4@vger.kernel.org" , James.Bottomley@steeleye.com, Jens Axboe , Milan Broz , Neil Brown To: Alasdair G Kergon Return-path: Received: from web32614.mail.mud.yahoo.com ([68.142.207.241]:46879 "HELO web32614.mail.mud.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1750972AbYAWLMk (ORCPT ); Wed, 23 Jan 2008 06:12:40 -0500 Sender: linux-ext4-owner@vger.kernel.org List-ID: ----- Original Message ---- > From: Alasdair G Kergon > To: Martin Knoblauch > Cc: Linus Torvalds ; Mel Gorman ; Fengguang Wu ; Mike Snitzer ; Peter Zijlstra ; jplatte@naasa.net; Ingo Molnar ; linux-kernel@vger.kernel.org; "linux-ext4@vger.kernel.org" ; James.Bottomley@steeleye.com; Jens Axboe ; Milan Broz ; Neil Brown > Sent: Wednesday, January 23, 2008 12:40:52 AM > Subject: Re: regression: 100% io-wait with 2.6.24-rcX > > On Tue, Jan 22, 2008 at 07:25:15AM -0800, Martin Knoblauch wrote: > > [root@lpsdm52 ~]# dmsetup table > > VolGroup00-LogVol02: 0 350945280 linear 104:2 67109248 > > VolGroup00-LogVol01: 0 8388608 linear 104:2 418054528 > > VolGroup00-LogVol00: 0 67108864 linear 104:2 384 > > The IO should pass straight through simple linear targets like > that without needing to get broken up, so I wouldn't expect those patches to > make any difference in this particular case. > Alasdair, LVM/DM are off the hook :-) I converted one box to direct using partitions and the performance is the same disappointment as with LVM/DM. Thanks anyway for looking at my problem. I will move the discussion now to a new thread, targetting CCISS directly. Cheers Martin