From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay3.corp.sgi.com [198.149.34.15]) by oss.sgi.com (Postfix) with ESMTP id 82C877F37 for ; Thu, 21 Mar 2013 16:12:40 -0500 (CDT) Received: from cuda.sgi.com (cuda3.sgi.com [192.48.176.15]) by relay3.corp.sgi.com (Postfix) with ESMTP id 0D21AAC006 for ; Thu, 21 Mar 2013 14:12:36 -0700 (PDT) Received: from ipmail06.adl6.internode.on.net (ipmail06.adl6.internode.on.net [150.101.137.145]) by cuda.sgi.com with ESMTP id rrOfKZFwPNqQR1k4 for ; Thu, 21 Mar 2013 14:12:35 -0700 (PDT) Date: Fri, 22 Mar 2013 08:12:18 +1100 From: Dave Chinner Subject: Re: [PATCH] xfstests: add execution of a custom command to fsstress (-x and -X options) Message-ID: <20130321211218.GP17758@dastard> References: <1363863585-25598-1-git-send-email-list.xfs@jan-o-sch.net> <20130321195054.GO17758@dastard> <514B72B9.1010005@jan-o-sch.net> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <514B72B9.1010005@jan-o-sch.net> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: Jan Schmidt Cc: xfs@oss.sgi.com On Thu, Mar 21, 2013 at 09:51:05PM +0100, Jan Schmidt wrote: > > > On 21.03.2013 20:50, Dave Chinner wrote: > > On Thu, Mar 21, 2013 at 11:59:45AM +0100, Jan Schmidt wrote: > >> From: Jan Schmidt > >> > >> This patch adds execution of a custom command in the middle of all fsstress > >> operations. Its intended use is the creation of snapshots in the middle of a > >> test run. > > > > Why do you need fsstress to do this? Why can't you just run fsstress > > in the background and run a loop creating periodic snapshots in the > > control script? > > Because I want reproducible results. Same random seed should result in > the very same snapshots being created. Why can't you run fsstress for N operations, run a snapshot, then run it again for M operations? That will give you exactly the same results, wouldn't it? > > Also, did you intend that every process creates a snapshot? i.e. it > > looks lik eif you run a 1000 processes, they'll all run a snapshot > > operation at X operations? i.e. this will generate nproc * X > > snapshots in a single run. This doesn't seem very wise to me.... > > Agreed, I haven't thought of running more than one process. For the sake > of reproducibility, I wouldn't want multiple processes for my test case > either. > > I'm not sure if there are other applications than snapshot creation for > such a feature, so I cannot argue whether to have each process execute > such a command or not. If such a feature is necessary, I'd suggest that implementing the snapshot ioctl as just another operation directly into fsstress is probably a better way to implement this functionality. That way you can control the frequency via the command line in exactly the same way as every other operation.... Cheers, Dave. -- Dave Chinner david@fromorbit.com _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs