From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Lord Subject: Re: kernel history of ide performance Date: Wed, 13 Apr 2005 14:57:53 -0400 Message-ID: <425D6BB1.1040904@rtr.ca> References: <1112690797.4252506dd574e@kiun.homelinux.net> <4252541B.3030209@gmx.de> <58cb370e050405021470f3a851@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from cpu1185.adsl.bellglobal.com ([207.236.110.166]:13969 "EHLO mail.rtr.ca") by vger.kernel.org with ESMTP id S261181AbVDMS55 (ORCPT ); Wed, 13 Apr 2005 14:57:57 -0400 In-Reply-To: <58cb370e050405021470f3a851@mail.gmail.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Bartlomiej Zolnierkiewicz Cc: "Oliver.Korpilla@gmx.de" , kiu , linux-ide@vger.kernel.org Note that hdparm has a "--direct" flag to perform O_DIRECT I/O, which can sometimes give different information than the default method. But the one weakness with 'hdparm -t' in either case, is that it performs a single READ at a time, rather than queuing up a pipeline full of READs. So it should always slightly under report achievable throughput. Cheers