From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from 0122700014.0.fullrate.dk ([95.166.99.235]:36939 "EHLO kernel.dk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750953Ab0BWJ2u (ORCPT ); Tue, 23 Feb 2010 04:28:50 -0500 Date: Tue, 23 Feb 2010 10:28:49 +0100 From: Jens Axboe Subject: Re: Verification failures with mixed read/write case Message-ID: <20100223092849.GP1025@kernel.dk> References: <1266456009.19149.72.camel@cfslap.wizy.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1266456009.19149.72.camel@cfslap.wizy.org> Sender: fio-owner@vger.kernel.org List-Id: fio@vger.kernel.org To: "Ricardo M. Correia" Cc: fio@vger.kernel.org On Thu, Feb 18 2010, Ricardo M. Correia wrote: > (Please CC me in the reply, I'm not subscribed) > > Hi, > > I've been observing verification failures with the following > configuration file: > > ----------- > [global] > ioengine=libaio > iodepth=30 > rw=randrw > bs=512-128k > direct=1 > rwmixcycle=40 > verify=sha256 > verify_async=8 > > [/dev/sda2] > -------------------- > > This happens on both RHEL5.4 and Ubuntu 9.10. > > I was observing that with fio-1.36, but I just tried cloning fio from > the git repo and I'm experiencing the same problem. > > Any ideas of what might be wrong? > > I found this email of a few months ago: > http://www.spinics.net/lists/fio/msg00205.html > > And I just verified that this patch is in my just-cloned git tree. Mixed read-write workloads generally don't work well with verify. The reason being that if you do verify && read, then fio will assume that you want to verify previously written data. That should not happen for a generated read as part of a mixed workload, I'll check what happens here. > Also, an unrelated issue is that fio complains about 'rwmixcycle' being > deprecated but the man page doesn't specify what parameter I should be > using instead. The time based approach didn't work well for buffered writes, so it was switched to an issue based count instead only. So you use rwmixread/rwmixwrite to set the percentages. -- Jens Axboe