Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752492AbXFWBbw (ORCPT ); Fri, 22 Jun 2007 21:31:52 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750925AbXFWBbm (ORCPT ); Fri, 22 Jun 2007 21:31:42 -0400 Received: from out4.smtp.messagingengine.com ([66.111.4.28]:58979 "EHLO out4.smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750875AbXFWBbh (ORCPT ); Fri, 22 Jun 2007 21:31:37 -0400 X-Sasl-enc: vqsnP2sDt6uSrUwqUiUCGBkyeqFQ9YvPZoTNjSa5gJrH 1182562315 Date: Fri, 22 Jun 2007 22:31:32 -0300 From: Henrique de Moraes Holschuh To: Carlo Wood , Arjan van de Ven , Jeff Garzik , linux-kernel@vger.kernel.org Subject: Re: SATA Harddisk speed drop of 100 MB/s Message-ID: <20070623013132.GA1702@khazad-dum.debian.net> References: <20070620224847.GA5488@alinoe.com> <4679B2DE.9090903@garzik.org> <1182397012.2863.0.camel@laptopd505.fenrus.org> <20070622162142.GA603@alinoe.com> <20070622211746.GB21769@khazad-dum.debian.net> <20070622212758.GA6970@alinoe.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070622212758.GA6970@alinoe.com> X-GPG-Fingerprint: 1024D/1CDB0FE3 5422 5C61 F6B7 06FB 7E04 3738 EE25 DE3F 1CDB 0FE3 User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1347 Lines: 35 Hi Carlo! On Fri, 22 Jun 2007, Carlo Wood wrote: > On Fri, Jun 22, 2007 at 06:17:46PM -0300, Henrique de Moraes Holschuh wrote: > > On Fri, 22 Jun 2007, Carlo Wood wrote: > > > So far I found out that it's RAID only. > > > > If you change the IO schedulers, does it help? > > How do I do that? for i in /sys/block/sd*/queue/scheduler ; do echo -n "scheduler for $i was:" ; cat $i ; echo anticipatory > $i ; done Should show you the scheduler for all libata/scsi discs, and switch to anticipatory. It probably works for hd* as well, but I don't have any around to test. I had ridiculous md raid performance (on resync) using cfq at least once. Unfortunately I never bothered trying to track it down, and I didn't check the throughput after the resync was done either. Also, I don't recall the kernel version, but it was either 2.6.18 or 2.6.20. Since it is a very simple test... -- "One disk to rule them all, One disk to find them. One disk to bring them all and in the darkness grind them. In the Land of Redmond where the shadows lie." -- The Silicon Valley Tarot Henrique Holschuh - 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/