From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mxi1.enovance.com ([94.143.114.217]:35283 "EHLO mxi1.enovance.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756032Ab3JJVBD (ORCPT ); Thu, 10 Oct 2013 17:01:03 -0400 Message-ID: <5257158A.2050707@enovance.com> Date: Thu, 10 Oct 2013 23:00:58 +0200 From: Erwan Velu MIME-Version: 1.0 Subject: Re: IO scheduler References: <52571453.4050101@nellans.org> In-Reply-To: <52571453.4050101@nellans.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: fio-owner@vger.kernel.org List-Id: fio@vger.kernel.org To: David Nellans Cc: "Brian L." , "fio@vger.kernel.org" On 10/10/2013 22:55, David Nellans wrote: > [...] > init 1 is overkill. In a previous life doing a lot of measuring of > flash - I found that simply making sure the machine was "idle" you > could get easily get repeatability within 1% for devices doing several > hundred thousand IOPS, even those with on-load architectures that were > sensitive to CPU usage. On my side, I've been creating a specific ramfs that does the fio testing I want. This way I'm sure that nothing else is running on my system (like daemons or gui stuff). That's a little bit extreme but it insures the same OS & environment to be used over & over making all my tests much more comparable over time. My 2 cents, Erwan,