Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757349AbXFYPSv (ORCPT ); Mon, 25 Jun 2007 11:18:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755897AbXFYPSn (ORCPT ); Mon, 25 Jun 2007 11:18:43 -0400 Received: from caffeine.uwaterloo.ca ([129.97.134.17]:50351 "EHLO caffeine.csclub.uwaterloo.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757277AbXFYPSm (ORCPT ); Mon, 25 Jun 2007 11:18:42 -0400 Date: Mon, 25 Jun 2007 11:18:41 -0400 To: Carlo Wood , Henrique de Moraes Holschuh , Arjan van de Ven , Jeff Garzik , linux-kernel@vger.kernel.org Subject: Re: SATA Harddisk speed drop of 100 MB/s Message-ID: <20070625151841.GK10008@csclub.uwaterloo.ca> 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> <20070623013132.GA1702@khazad-dum.debian.net> <20070623025906.GA24336@alinoe.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070623025906.GA24336@alinoe.com> User-Agent: Mutt/1.5.13 (2006-08-11) From: lsorense@csclub.uwaterloo.ca (Lennart Sorensen) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1343 Lines: 36 On Sat, Jun 23, 2007 at 04:59:06AM +0200, Carlo Wood wrote: > Just one kernel version? The problem here is in every > kernel revision after 551c012d7eea3dc5ec063c7ff9c718d39e77634f > > 2.6.20-rc2,rc3,rc4,rc5,rc6,rc7 ... 2.6.20 ... 2.6.21 ... 2.6.22-rc5 > > noop: > Timing buffered disk reads: 254 MB in 3.00 seconds = 84.66 MB/sec > > anticipatory: > Timing buffered disk reads: 252 MB in 3.02 seconds = 83.43 MB/sec > > deadline: > Timing buffered disk reads: 258 MB in 3.02 seconds = 85.41 MB/sec > > cfq: > Timing buffered disk reads: 194 MB in 3.03 seconds = 64.06 MB/sec > > The normal value is cfq. So, all other schedulars are somewhat faster, > but still far from the correct 165 MB/s. How do you know 165MB/s is correct? As for 10k rpm being faster, well remember rotation speed _and_ areal density is what gives transfer rate. a 750GB 7200rpm is likely able to have a higher throughput than a 73GB 10k rpm drive since more bits pass by the head in any given unit of time on the larger drive. The 7200 rpm has a slower average access time though. -- Len Sorensen - 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/