From: Mike Snitzer <snitzer@redhat.com>
To: Sagi Grimberg <sagig@dev.mellanox.co.il>
Cc: axboe@kernel.dk, Christoph Hellwig <hch@infradead.org>,
"linux-nvme@lists.infradead.org" <linux-nvme@lists.infradead.org>,
"keith.busch@intel.com" <keith.busch@intel.com>,
device-mapper development <dm-devel@redhat.com>,
Bart Van Assche <bart.vanassche@sandisk.com>
Subject: Re: dm-multipath low performance with blk-mq
Date: Wed, 27 Jan 2016 13:42:46 -0500 [thread overview]
Message-ID: <20160127184245.GC31802@redhat.com> (raw)
In-Reply-To: <56A904B6.50407@dev.mellanox.co.il>
On Wed, Jan 27 2016 at 12:56pm -0500,
Sagi Grimberg <sagig@dev.mellanox.co.il> wrote:
>
>
> On 27/01/2016 19:48, Mike Snitzer wrote:
> >
> >BTW, I _cannot_ get null_blk to come even close to your reported 1500K+
> >IOPs on 2 "fast" systems I have access to. Which arguments are you
> >loading the null_blk module with?
> >
> >I've been using:
> >modprobe null_blk gb=4 bs=4096 nr_devices=1 queue_mode=2 submit_queues=12
>
> $ for f in /sys/module/null_blk/parameters/*; do echo $f; cat $f; done
> /sys/module/null_blk/parameters/bs
> 512
> /sys/module/null_blk/parameters/completion_nsec
> 10000
> /sys/module/null_blk/parameters/gb
> 250
> /sys/module/null_blk/parameters/home_node
> -1
> /sys/module/null_blk/parameters/hw_queue_depth
> 64
> /sys/module/null_blk/parameters/irqmode
> 1
> /sys/module/null_blk/parameters/nr_devices
> 2
> /sys/module/null_blk/parameters/queue_mode
> 2
> /sys/module/null_blk/parameters/submit_queues
> 24
> /sys/module/null_blk/parameters/use_lightnvm
> N
> /sys/module/null_blk/parameters/use_per_node_hctx
> N
>
> $ fio --group_reporting --rw=randread --bs=4k --numjobs=24
> --iodepth=32 --runtime=99999999 --time_based --loops=1
> --ioengine=libaio --direct=1 --invalidate=1 --randrepeat=1
> --norandommap --exitall --name task_nullb0 --filename=/dev/nullb0
> task_nullb0: (g=0): rw=randread, bs=4K-4K/4K-4K/4K-4K,
> ioengine=libaio, iodepth=32
> ...
> fio-2.1.10
> Starting 24 processes
> Jobs: 24 (f=24): [rrrrrrrrrrrrrrrrrrrrrrrr] [0.0% done]
> [7234MB/0KB/0KB /s] [1852K/0/0 iops] [eta 1157d:09h:46m:22s]
Thanks, the number of fio threads was pretty important. I'm still
seeing better IOPs with queue_mode=0 (bio-based).
Jobs: 24 (f=24): [r(24)] [11.7% done] [11073MB/0KB/0KB /s] [2835K/0/0 iops] [eta 14m:42s]
(with queue_mode=2 I get ~1930K IOPs.. which I need to use to stack
request-based DM multipath ontop)
Now I can focus on why dm-multipath is slow...
WARNING: multiple messages have this Message-ID (diff)
From: snitzer@redhat.com (Mike Snitzer)
Subject: dm-multipath low performance with blk-mq
Date: Wed, 27 Jan 2016 13:42:46 -0500 [thread overview]
Message-ID: <20160127184245.GC31802@redhat.com> (raw)
In-Reply-To: <56A904B6.50407@dev.mellanox.co.il>
On Wed, Jan 27 2016 at 12:56pm -0500,
Sagi Grimberg <sagig@dev.mellanox.co.il> wrote:
>
>
> On 27/01/2016 19:48, Mike Snitzer wrote:
> >
> >BTW, I _cannot_ get null_blk to come even close to your reported 1500K+
> >IOPs on 2 "fast" systems I have access to. Which arguments are you
> >loading the null_blk module with?
> >
> >I've been using:
> >modprobe null_blk gb=4 bs=4096 nr_devices=1 queue_mode=2 submit_queues=12
>
> $ for f in /sys/module/null_blk/parameters/*; do echo $f; cat $f; done
> /sys/module/null_blk/parameters/bs
> 512
> /sys/module/null_blk/parameters/completion_nsec
> 10000
> /sys/module/null_blk/parameters/gb
> 250
> /sys/module/null_blk/parameters/home_node
> -1
> /sys/module/null_blk/parameters/hw_queue_depth
> 64
> /sys/module/null_blk/parameters/irqmode
> 1
> /sys/module/null_blk/parameters/nr_devices
> 2
> /sys/module/null_blk/parameters/queue_mode
> 2
> /sys/module/null_blk/parameters/submit_queues
> 24
> /sys/module/null_blk/parameters/use_lightnvm
> N
> /sys/module/null_blk/parameters/use_per_node_hctx
> N
>
> $ fio --group_reporting --rw=randread --bs=4k --numjobs=24
> --iodepth=32 --runtime=99999999 --time_based --loops=1
> --ioengine=libaio --direct=1 --invalidate=1 --randrepeat=1
> --norandommap --exitall --name task_nullb0 --filename=/dev/nullb0
> task_nullb0: (g=0): rw=randread, bs=4K-4K/4K-4K/4K-4K,
> ioengine=libaio, iodepth=32
> ...
> fio-2.1.10
> Starting 24 processes
> Jobs: 24 (f=24): [rrrrrrrrrrrrrrrrrrrrrrrr] [0.0% done]
> [7234MB/0KB/0KB /s] [1852K/0/0 iops] [eta 1157d:09h:46m:22s]
Thanks, the number of fio threads was pretty important. I'm still
seeing better IOPs with queue_mode=0 (bio-based).
Jobs: 24 (f=24): [r(24)] [11.7% done] [11073MB/0KB/0KB /s] [2835K/0/0 iops] [eta 14m:42s]
(with queue_mode=2 I get ~1930K IOPs.. which I need to use to stack
request-based DM multipath ontop)
Now I can focus on why dm-multipath is slow...
next prev parent reply other threads:[~2016-01-27 18:42 UTC|newest]
Thread overview: 127+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-01-18 12:04 dm-multipath low performance with blk-mq Sagi Grimberg
2016-01-19 10:37 ` Sagi Grimberg
2016-01-19 22:45 ` Mike Snitzer
2016-01-19 22:45 ` Mike Snitzer
2016-01-25 21:40 ` Mike Snitzer
2016-01-25 21:40 ` Mike Snitzer
2016-01-25 23:37 ` Benjamin Marzinski
2016-01-25 23:37 ` [dm-devel] " Benjamin Marzinski
2016-01-26 13:29 ` Mike Snitzer
2016-01-26 13:29 ` Mike Snitzer
2016-01-26 14:01 ` Hannes Reinecke
2016-01-26 14:47 ` Mike Snitzer
2016-01-26 14:47 ` Mike Snitzer
2016-01-26 14:56 ` Christoph Hellwig
2016-01-26 14:56 ` Christoph Hellwig
2016-01-26 15:27 ` Mike Snitzer
2016-01-26 15:27 ` Mike Snitzer
2016-01-26 15:57 ` Benjamin Marzinski
2016-01-27 11:14 ` Sagi Grimberg
2016-01-27 11:14 ` Sagi Grimberg
2016-01-27 17:48 ` Mike Snitzer
2016-01-27 17:48 ` Mike Snitzer
2016-01-27 17:51 ` Jens Axboe
2016-01-27 17:51 ` Jens Axboe
2016-01-27 18:16 ` Mike Snitzer
2016-01-27 18:16 ` Mike Snitzer
2016-01-27 18:26 ` Jens Axboe
2016-01-27 18:26 ` Jens Axboe
2016-01-27 19:14 ` Mike Snitzer
2016-01-27 19:14 ` Mike Snitzer
2016-01-27 19:50 ` Jens Axboe
2016-01-27 19:50 ` Jens Axboe
2016-01-27 17:56 ` Sagi Grimberg
2016-01-27 17:56 ` Sagi Grimberg
2016-01-27 18:42 ` Mike Snitzer [this message]
2016-01-27 18:42 ` Mike Snitzer
2016-01-27 19:49 ` Jens Axboe
2016-01-27 19:49 ` Jens Axboe
2016-01-27 20:45 ` Mike Snitzer
2016-01-27 20:45 ` Mike Snitzer
2016-01-29 23:35 ` Mike Snitzer
2016-01-29 23:35 ` Mike Snitzer
2016-01-30 8:52 ` Hannes Reinecke
2016-01-30 8:52 ` Hannes Reinecke
2016-01-30 19:12 ` Mike Snitzer
2016-01-30 19:12 ` Mike Snitzer
2016-02-01 6:46 ` Hannes Reinecke
2016-02-01 6:46 ` Hannes Reinecke
2016-02-03 18:04 ` Mike Snitzer
2016-02-03 18:04 ` Mike Snitzer
2016-02-03 18:24 ` Mike Snitzer
2016-02-03 18:24 ` Mike Snitzer
2016-02-03 19:22 ` Mike Snitzer
2016-02-03 19:22 ` Mike Snitzer
2016-02-04 6:54 ` Hannes Reinecke
2016-02-04 6:54 ` Hannes Reinecke
2016-02-04 13:54 ` Mike Snitzer
2016-02-04 13:54 ` Mike Snitzer
2016-02-04 13:58 ` Hannes Reinecke
2016-02-04 13:58 ` Hannes Reinecke
2016-02-04 14:09 ` Mike Snitzer
2016-02-04 14:09 ` Mike Snitzer
2016-02-04 14:32 ` Hannes Reinecke
2016-02-04 14:32 ` Hannes Reinecke
2016-02-04 14:44 ` Mike Snitzer
2016-02-04 14:44 ` Mike Snitzer
2016-02-05 15:13 ` [RFC PATCH] dm: fix excessive dm-mq context switching Mike Snitzer
2016-02-05 15:13 ` Mike Snitzer
2016-02-05 18:05 ` Mike Snitzer
2016-02-05 18:05 ` Mike Snitzer
2016-02-05 19:19 ` Mike Snitzer
2016-02-05 19:19 ` Mike Snitzer
2016-02-07 15:41 ` Sagi Grimberg
2016-02-07 15:41 ` Sagi Grimberg
2016-02-07 16:07 ` Mike Snitzer
2016-02-07 16:07 ` Mike Snitzer
2016-02-07 16:42 ` Sagi Grimberg
2016-02-07 16:42 ` Sagi Grimberg
2016-02-07 16:37 ` Bart Van Assche
2016-02-07 16:37 ` Bart Van Assche
2016-02-07 16:43 ` Sagi Grimberg
2016-02-07 16:43 ` Sagi Grimberg
2016-02-07 16:53 ` Mike Snitzer
2016-02-07 16:53 ` Mike Snitzer
2016-02-07 16:54 ` Sagi Grimberg
2016-02-07 16:54 ` Sagi Grimberg
2016-02-07 17:20 ` Mike Snitzer
2016-02-07 17:20 ` Mike Snitzer
2016-02-08 12:21 ` Sagi Grimberg
2016-02-08 12:21 ` Sagi Grimberg
2016-02-08 14:34 ` Mike Snitzer
2016-02-08 14:34 ` Mike Snitzer
2016-02-09 7:50 ` Hannes Reinecke
2016-02-09 7:50 ` Hannes Reinecke
2016-02-09 14:55 ` Mike Snitzer
2016-02-09 14:55 ` Mike Snitzer
2016-02-09 15:32 ` Hannes Reinecke
2016-02-09 15:32 ` Hannes Reinecke
2016-02-10 0:45 ` Mike Snitzer
2016-02-10 0:45 ` Mike Snitzer
2016-02-11 1:50 ` RCU-ified dm-mpath for testing/review Mike Snitzer
2016-02-11 3:35 ` Mike Snitzer
2016-02-11 3:35 ` Mike Snitzer
2016-02-11 15:34 ` Mike Snitzer
2016-02-11 15:34 ` Mike Snitzer
2016-02-12 15:18 ` Hannes Reinecke
2016-02-12 15:18 ` Hannes Reinecke
2016-02-12 15:26 ` Mike Snitzer
2016-02-12 15:26 ` Mike Snitzer
2016-02-12 16:04 ` Hannes Reinecke
2016-02-12 16:04 ` Hannes Reinecke
2016-02-12 18:00 ` Mike Snitzer
2016-02-12 18:00 ` Mike Snitzer
2016-02-15 6:47 ` Hannes Reinecke
2016-02-15 6:47 ` Hannes Reinecke
2016-01-26 1:49 ` dm-multipath low performance with blk-mq Benjamin Marzinski
2016-01-26 1:49 ` [dm-devel] " Benjamin Marzinski
2016-01-26 16:03 ` Mike Snitzer
2016-01-26 16:03 ` Mike Snitzer
2016-01-26 16:44 ` Christoph Hellwig
2016-01-26 16:44 ` Christoph Hellwig
2016-01-27 2:09 ` Mike Snitzer
2016-01-27 2:09 ` Mike Snitzer
2016-01-27 11:10 ` Sagi Grimberg
2016-01-27 11:10 ` Sagi Grimberg
2016-01-26 21:40 ` Benjamin Marzinski
2016-01-26 21:40 ` [dm-devel] " Benjamin Marzinski
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