From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755505AbXFYQES (ORCPT ); Mon, 25 Jun 2007 12:04:18 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752441AbXFYQEJ (ORCPT ); Mon, 25 Jun 2007 12:04:09 -0400 Received: from viefep18-int.chello.at ([213.46.255.22]:10292 "EHLO viefep14-int.chello.at" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752259AbXFYQEI (ORCPT ); Mon, 25 Jun 2007 12:04:08 -0400 Date: Mon, 25 Jun 2007 18:04:12 +0200 From: Carlo Wood To: Lennart Sorensen Cc: 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: <20070625160412.GB2432@alinoe.com> Mail-Followup-To: Carlo Wood , Lennart Sorensen , Henrique de Moraes Holschuh , Arjan van de Ven , Jeff Garzik , linux-kernel@vger.kernel.org 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> <20070625151841.GK10008@csclub.uwaterloo.ca> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070625151841.GK10008@csclub.uwaterloo.ca> User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jun 25, 2007 at 11:18:41AM -0400, Lennart Sorensen wrote: > How do you know 165MB/s is correct? It is the maximum value I measure. It's also the value that I measure consistently with NCQ off, like with 2.6.18. Finally, even before I bought this PC, I did some research and the RAID with Raptors was recommended by someone with a lot of experience with them. He told me that I could count on (N - 1) * 75 MB/s (on average) for an array with N disks. I had expected 150 MB/s, which is about what I get. The 165 MB/s is on the outside of the disk (low partition). -- Carlo Wood