From: Dave Chinner Subject: Re: [ANNOUNCE] fsperf: a simple fs/block performance testing framework Date: Tue, 10 Oct 2017 08:09:20 +1100 Message-ID: <20171009210920.GO3666@dastard> References: <20171006210956.vf326sydjiphsefo@destiny> <20171009005137.GA3666@dastard> <20171009022509.rz6goq3sec5ppxrr@destiny> <20171009051731.GK3666@dastard> <20171009130050.ufnmdhslc53bwpgc@destiny> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-fsdevel@vger.kernel.org, kernel-team@fb.com, linux-btrfs@vger.kernel.org, linux-block@vger.kernel.org, linux-ext4@vger.kernel.org, linux-xfs@vger.kernel.org, linux-kernel@vger.kernel.org To: Josef Bacik Return-path: Content-Disposition: inline In-Reply-To: <20171009130050.ufnmdhslc53bwpgc@destiny> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org On Mon, Oct 09, 2017 at 09:00:51AM -0400, Josef Bacik wrote: > On Mon, Oct 09, 2017 at 04:17:31PM +1100, Dave Chinner wrote: > > On Sun, Oct 08, 2017 at 10:25:10PM -0400, Josef Bacik wrote: > > > > Integrating into fstests means it will be immediately available to > > > > all fs developers, it'll run on everything that everyone already has > > > > setup for filesystem testing, and it will have familiar mkfs/mount > > > > option setup behaviour so there's no new hoops for everyone to jump > > > > through to run it... > > > > > > > > > > TBF I specifically made it as easy as possible because I know we all hate trying > > > to learn new shit. > > > > Yeah, it's also hard to get people to change their workflows to add > > a whole new test harness into them. It's easy if it's just a new > > command to an existing workflow :P > > > > Agreed, so if you probably won't run this outside of fstests then I'll add it to > xfstests. I envision this tool as being run by maintainers to verify their pull > requests haven't regressed since the last set of patches, as well as by anybody > trying to fix performance problems. So it's way more important to me that you, > Ted, and all the various btrfs maintainers will run it than anybody else. > > > > I figured this was different enough to warrant a separate > > > project, especially since I'm going to add block device jobs so Jens can test > > > block layer things. If we all agree we'd rather see this in fstests then I'm > > > happy to do that too. Thanks, > > > > I'm not fussed either way - it's a good discussion to have, though. > > > > If I want to add tests (e.g. my time-honoured fsmark tests), where > > should I send patches? > > > > I beat you to that! I wanted to avoid adding fs_mark to the suite because it > means parsing another different set of outputs, so I added a new ioengine to fio > for this > > http://www.spinics.net/lists/fio/msg06367.html > > and added a fio job to do 500k files > > https://github.com/josefbacik/fsperf/blob/master/tests/500kemptyfiles.fio > > The test is disabled by default for now because obviously the fio support hasn't > landed yet. That seems .... misguided. fio is good, but it's not a universal solution. > I'd _like_ to expand fio for cases we come up with that aren't possible, as > there's already a ton of measurements that are taken, especially around > latencies. To be properly useful it needs to support more than just fio to run tests. Indeed, it's largely useless to me if that's all it can do or it's a major pain to add support for different tools like fsmark. e.g. my typical perf regression test that you see the concurrnet fsmark create workload is actually a lot more. It does: fsmark to create 50m zero length files umount, run parallel xfs_repair (excellent mmap_sem/page fault punisher) mount run parallel find -ctime (readdir + lookup traversal) unmount, mount run parallel ls -R (readdir + dtype traversal) unmount, mount parallel rm -rf of 50m files I have variants that use small 4k files or large files rather than empty files, taht use different fsync patterns to stress the log, use grep -R to traverse the data as well as the directory/inode structure instead of find, etc. > That said I'm not opposed to throwing new stuff in there, it just > means we have to add stuff to parse the output and store it in the database in a > consistent way, which seems like more of a pain than just making fio do what we > need it to. Thanks, fio is not going to be able to replace the sort of perf tests I run from week to week. If that's all it's going to do then it's not directly useful to me... Cheers, Dave. -- Dave Chinner david@fromorbit.com