From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Snitzer Subject: FIXED! [was: awful request merge results while simulating high IOPS] multipath Date: Tue, 24 Feb 2015 23:38:08 -0500 Message-ID: <20150225043808.GA14060@redhat.com> References: <1424796250-38553-1-git-send-email-snitzer@redhat.com> <1424796250-38553-5-git-send-email-snitzer@redhat.com> <54ECAC08.7040603@kernel.dk> <20150224172259.GA39226@redhat.com> <54ECBA78.6020204@kernel.dk> <20150224181257.GA11444@redhat.com> <54ECC000.40604@kernel.dk> <20150224183256.GA11566@redhat.com> <20150225005608.GA13348@redhat.com> Reply-To: device-mapper development Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20150225005608.GA13348@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: Jens Axboe Cc: Keith Busch , jmoyer@redhat.com, shivakrishna.merla@netapp.com, dm-devel@redhat.com, Bart Van Assche List-Id: dm-devel.ids New multipath results using these 2 additional DM patches: https://git.kernel.org/cgit/linux/kernel/git/device-mapper/linux-dm.git/commit/?h=for-next&id=d379ecbac533d3ac45c7f155b1fc1b760abace6e https://git.kernel.org/cgit/linux/kernel/git/device-mapper/linux-dm.git/commit/?h=for-next&id=d379ecbac533d3ac45c7f155b1fc1b760abace6e (the important one being the last patch, thanks to Jens for the suggestion!) Both deadline and noop schedulers work really well this fio test now (cfq is slightly slower): [64_seq_write] #filename=/dev/mapper/skd_mpath filename=/dev/dm-7 rw=write rwmixread=0 blocksize=4k iodepth=16 direct=1 numjobs=64 runtime=100 ioengine=libaio time_based deadline: --------- Run status group 0 (all jobs): WRITE: io=64402MB, aggrb=659426KB/s, minb=8960KB/s, maxb=10348KB/s, mint=100001msec, maxt=100007msec Disk stats (read/write): dm-7: ios=78/951571, merge=0/14721874, ticks=1/6766375, in_queue=6868921, util=100.00%, aggrios=257/951897, aggrmerge=0/0, aggrticks=3/3467932, aggrin_queue=3467835, aggrutil=99.09% skd0: ios=257/951897, merge=0/0, ticks=3/3467932, in_queue=3467835, util=99.09% (deadline is _really_ fast with this test now, noop is fast too, see below) cfq: ---- rotational=0 ------------ Run status group 0 (all jobs): WRITE: io=18719MB, aggrb=191652KB/s, minb=2639KB/s, maxb=4210KB/s, mint=100001msec, maxt=100018msec Disk stats (read/write): dm-7: ios=91/368755, merge=0/4407385, ticks=2/6783504, in_queue=6815287, util=100.00%, aggrios=273/368851, aggrmerge=0/0, aggrticks=5/2962495, aggrin_queue=2962487, aggrutil=95.40% skd0: ios=273/368851, merge=0/0, ticks=5/2962495, in_queue=2962487, util=95.40% rotational=1 ------------ Run status group 0 (all jobs): WRITE: io=19660MB, aggrb=200940KB/s, minb=2304KB/s, maxb=6441KB/s, mint=100001msec, maxt=100188msec Disk stats (read/write): dm-7: ios=91/786111, merge=0/4179472, ticks=2/5820606, in_queue=5834058, util=99.98%, aggrios=182/786507, aggrmerge=0/0, aggrticks=4/131800, aggrin_queue=131758, aggrutil=70.55% skd0: ios=182/786507, merge=0/0, ticks=4/131800, in_queue=131758, util=70.55% noop: ----- Run status group 0 (all jobs): WRITE: io=58264MB, aggrb=596517KB/s, minb=9301KB/s, maxb=9354KB/s, mint=100001msec, maxt=100018msec Disk stats (read/write): dm-7: ios=116/998937, merge=0/13874486, ticks=4/6853397, in_queue=6934793, util=100.00%, aggrios=295/999061, aggrmerge=0/0, aggrticks=8/3776141, aggrin_queue=3776117, aggrutil=98.81% skd0: ios=295/999061, merge=0/0, ticks=8/3776141, in_queue=3776117, util=98.81%