From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.fusionio.com ([64.244.102.30]:33860 "EHLO mx1.fusionio.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755320Ab0KJTwt (ORCPT ); Wed, 10 Nov 2010 14:52:49 -0500 Message-ID: <4CDAF809.6010709@fusionio.com> Date: Wed, 10 Nov 2010 20:52:41 +0100 From: Jens Axboe MIME-Version: 1.0 Subject: Re: IOPS higher than expected on randwrite, direct=1 tests References: <20101109182801.GP15588@sebastiankayser.de> <20101110082223.GB14261@sebastiankayser.de> <4CDAA783.9050902@fusionio.com> <20101110171856.GI28050@sebastiankayser.de> <20101110185826.GJ28050@sebastiankayser.de> In-Reply-To: Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Sender: fio-owner@vger.kernel.org List-Id: fio@vger.kernel.org To: John Cagle Cc: Sebastian Kayser , "fio@vger.kernel.org" On 2010-11-10 20:50, John Cagle wrote: > If the disk is 2TB, then your 100GB test is only using 5% of it-- thus > your observed IOPS will be a lot better than expected due to > short-stroking. Right? That is also true, but probably not that much. See my previous email, rotational latency should dominate here. -- Jens Axboe