From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.fusionio.com ([64.244.102.31]:54937 "EHLO mx2.fusionio.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756187Ab1D2Jos (ORCPT ); Fri, 29 Apr 2011 05:44:48 -0400 Received: from mail1.int.fusionio.com (mail1.int.fusionio.com [10.101.1.21]) by mx2.fusionio.com with ESMTP id 3Rxt4dsPYnwLPnZz for ; Fri, 29 Apr 2011 03:44:39 -0600 (MDT) Message-ID: <4DBA8884.5040605@fusionio.com> Date: Fri, 29 Apr 2011 11:44:36 +0200 From: Jens Axboe MIME-Version: 1.0 Subject: Fio 1.52 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: "fio@vger.kernel.org" Hi, I have tagged version 1.52 of fio. There's not much exciting since 1.51, but one change in particular warrants a note. As of 1.52, the random generator used for generating IO offset for random workloads has been changed. We used to rely on the one supplied by glibc (and similar on other platforms), but this has a few down sides: - We did not necessarily generate the same sequences on all platforms. - Our internal generator is faster and from some testing of higher quality than the glibc provided one. So on the plus side we now generate the same IO patterns on all platforms. The only real downside is that we do not generate the same IO patterns as 1.51 and previous. This _should_ not cause any issues, since the pattern should be equally random. But it will be different. So it is something to keep in mind, if people use fio for regression runs and watch performance. We are not at the point where manufacturers will optimize for a fio workload, so I don't envision any issues from this change :-) -- Jens Axboe