From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933084AbXDFVb1 (ORCPT ); Fri, 6 Apr 2007 17:31:27 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S933100AbXDFVb1 (ORCPT ); Fri, 6 Apr 2007 17:31:27 -0400 Received: from mail.tmr.com ([64.65.253.246]:59286 "EHLO gaimboi.tmr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933084AbXDFVbZ (ORCPT ); Fri, 6 Apr 2007 17:31:25 -0400 Message-ID: <4616BC95.8070009@tmr.com> Date: Fri, 06 Apr 2007 17:33:09 -0400 From: Bill Davidsen User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8.0.8) Gecko/20061105 SeaMonkey/1.0.6 MIME-Version: 1.0 To: Paa Paa CC: nickpiggin@yahoo.com.au, linux-kernel@vger.kernel.org Subject: Re: Lower HD transfer rate with NCQ enabled? References: <46121BCF.50401@yahoo.com.au> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Paa Paa wrote: >>> Q: What conclusion can I make on "hdparm -t" results or can I make >>> any conclusions? Do I really have lower performance with NCQ or not? >>> If I do, is this because of my HD or because of kernel? >> >> What IO scheduler are you using? If AS or CFQ, could you try with >> deadline? > > I was using CFQ. I now tried with Deadline and that doesn't seem to > degrade the performance at all! With Deadline I got 60MB/s both with and > without NCQ. This was with "hdparm -t". > > So what does this tell us? > It suggests that it's time to test with real load and see if deadline works well for you in the general case. -- Bill Davidsen "We have more to fear from the bungling of the incompetent than from the machinations of the wicked." - from Slashdot