RE: [PATCH v3] mmc: rtsx: improve performance for multi block rw

From: Ricky WU
Date: Fri Dec 24 2021 - 02:23:53 EST


> -----Original Message-----
> From: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
> Sent: Thursday, December 23, 2021 6:37 PM
> To: Ricky WU <ricky_wu@xxxxxxxxxxx>
> Cc: tommyhebb@xxxxxxxxx; linux-mmc@xxxxxxxxxxxxxxx;
> linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH v3] mmc: rtsx: improve performance for multi block rw
>
> On Thu, 23 Dec 2021 at 11:27, Ricky WU <ricky_wu@xxxxxxxxxxx> wrote:
> >
> > > -----Original Message-----
> > > From: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
> > > Sent: Tuesday, December 21, 2021 8:51 PM
> > > To: Ricky WU <ricky_wu@xxxxxxxxxxx>
> > > Cc: tommyhebb@xxxxxxxxx; linux-mmc@xxxxxxxxxxxxxxx;
> > > linux-kernel@xxxxxxxxxxxxxxx
> > > Subject: Re: [PATCH v3] mmc: rtsx: improve performance for multi
> > > block rw
> > >
> > > On Tue, 21 Dec 2021 at 13:24, Ricky WU <ricky_wu@xxxxxxxxxxx> wrote:
> > > >
> > > > Improving performance for the CMD is multi-block read/write and
> > > > the data is sequential.
> > > > sd_check_multi_seq() to distinguish multi-block RW (CMD 18/25) or
> > > > normal RW (CMD 17/24) if the CMD is multi-block and the data is
> > > > sequential then call to sd_rw_multi_seq()
> > > >
> > > > This patch mainly to control the timing of reply at CMD 12/13.
> > > > Originally code driver reply CMD 12/13 at every RW (CMD 18/25).
> > > > The new code to distinguish multi-block RW(CMD 18/25) and the data
> > > > is sequential or not, if the data is sequential RW driver do not
> > > > send CMD
> > > > 12 and bypass CMD 13 until wait the different direction RW CMD or
> > > > trigger the delay_work to sent CMD 12.
> > > >
> > > > run benchmark result as below:
> > > > SD Card : Samsumg Pro Plus 128GB
> > > > Number of Samples:100, Sample Size:10MB <Before> Read : 86.9 MB/s,
> > > > Write : 38.3 MB/s <After> Read : 91.5 MB/s, Write : 55.5 MB/s
> > >
> > > A much nicer commit message, thanks a lot! Would you mind running
> > > some additional tests, like random I/O read/writes?
> > >
> > > Also, please specify the benchmark tool and command you are using.
> > > In the meantime, I will continue to look at the code.
> > >
> >
> > The Tool just use Ubuntu internal GUI benchmark Tool in the "Disks"
> > and the Tool don't have random I/O to choice...
> >
> > Do you have any suggestion for testing random I/O But we think random
> > I/O will not change much
>
> I would probably look into using fio, https://fio.readthedocs.io/en/latest/
>

Filled random I/O data
Before the patch:
CMD (Randread):
sudo fio -filename=/dev/mmcblk0 -direct=1 -numjobs=1 -thread -group_reporting -ioengine=psync -iodepth=1 -size=1G -name=mytest -bs=1M -rw=randread

mytest: (g=0): rw=randread, bs=(R) 1024KiB-1024KiB, (W) 1024KiB-1024KiB, (T) 1024KiB-1024KiB, ioengine=psync, iodepth=1
fio-3.16
Starting 1 thread
Jobs: 1 (f=1): [r(1)][100.0%][r=86.0MiB/s][r=86 IOPS][eta 00m:00s]
mytest: (groupid=0, jobs=1): err= 0: pid=2663: Fri Dec 24 14:28:33 2021
read: IOPS=85, BW=85.1MiB/s (89.3MB/s)(1024MiB/12026msec)
clat (usec): min=11253, max=34579, avg=11735.57, stdev=742.16
lat (usec): min=11254, max=34580, avg=11736.34, stdev=742.16
clat percentiles (usec):
| 1.00th=[11338], 5.00th=[11469], 10.00th=[11600], 20.00th=[11600],
| 30.00th=[11600], 40.00th=[11600], 50.00th=[11731], 60.00th=[11731],
| 70.00th=[11863], 80.00th=[11863], 90.00th=[11863], 95.00th=[11863],
| 99.00th=[11863], 99.50th=[12518], 99.90th=[15664], 99.95th=[34341],
| 99.99th=[34341]
bw ( KiB/s): min=81920, max=88064, per=99.91%, avg=87110.67, stdev=1467.81, samples=24
iops : min= 80, max= 86, avg=85.00, stdev= 1.41, samples=24
lat (msec) : 20=99.90%, 50=0.10%
cpu : usr=0.17%, sys=1.26%, ctx=2048, majf=0, minf=256
IO depths : 1=100.0%, 2=0.0%, 4=0.0%, 8=0.0%, 16=0.0%, 32=0.0%, >=64=0.0%
submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
issued rwts: total=1024,0,0,0 short=0,0,0,0 dropped=0,0,0,0
latency : target=0, window=0, percentile=100.00%, depth=1

Run status group 0 (all jobs):
READ: bw=85.1MiB/s (89.3MB/s), 85.1MiB/s-85.1MiB/s (89.3MB/s-89.3MB/s), io=1024MiB (1074MB), run=12026-12026msec

Disk stats (read/write):
mmcblk0: ios=2026/0, merge=0/0, ticks=17612/0, in_queue=17612, util=99.23%

CMD (Randwrite):
sudo fio -filename=/dev/mmcblk0 -direct=1 -numjobs=1 -thread -group_reporting -ioengine=psync -iodepth=1 -size=1G -name=mytest -bs=1M -rw=randwrite

mytest: (g=0): rw=randwrite, bs=(R) 1024KiB-1024KiB, (W) 1024KiB-1024KiB, (T) 1024KiB-1024KiB, ioengine=psync, iodepth=1
fio-3.16
Starting 1 thread
Jobs: 1 (f=1): [w(1)][100.0%][w=41.0MiB/s][w=41 IOPS][eta 00m:00s]
mytest: (groupid=0, jobs=1): err= 0: pid=2738: Fri Dec 24 14:30:05 2021
write: IOPS=38, BW=38.4MiB/s (40.2MB/s)(1024MiB/26695msec); 0 zone resets
clat (usec): min=18862, max=94708, avg=25990.34, stdev=9227.22
lat (usec): min=18910, max=94781, avg=26061.91, stdev=9228.04
clat percentiles (usec):
| 1.00th=[20579], 5.00th=[22414], 10.00th=[22676], 20.00th=[22938],
| 30.00th=[23200], 40.00th=[23462], 50.00th=[23462], 60.00th=[23725],
| 70.00th=[23725], 80.00th=[23987], 90.00th=[24773], 95.00th=[56361],
| 99.00th=[59507], 99.50th=[64226], 99.90th=[86508], 99.95th=[94897],
| 99.99th=[94897]
bw ( KiB/s): min=24576, max=43008, per=99.85%, avg=39221.13, stdev=3860.74, samples=53
iops : min= 24, max= 42, avg=38.30, stdev= 3.77, samples=53
lat (msec) : 20=0.98%, 50=92.38%, 100=6.64%
cpu : usr=0.50%, sys=0.31%, ctx=1024, majf=0, minf=0
IO depths : 1=100.0%, 2=0.0%, 4=0.0%, 8=0.0%, 16=0.0%, 32=0.0%, >=64=0.0%
submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
issued rwts: total=0,1024,0,0 short=0,0,0,0 dropped=0,0,0,0
latency : target=0, window=0, percentile=100.00%, depth=1

Run status group 0 (all jobs):
WRITE: bw=38.4MiB/s (40.2MB/s), 38.4MiB/s-38.4MiB/s (40.2MB/s-40.2MB/s), io=1024MiB (1074MB), run=26695-26695msec

Disk stats (read/write):
mmcblk0: ios=52/2043, merge=0/0, ticks=81/39874, in_queue=39956, util=99.90%


After the patch:

CMD (Randread):
sudo fio -filename=/dev/mmcblk0 -direct=1 -numjobs=1 -thread -group_reporting -ioengine=psync -iodepth=1 -size=1G -name=mytest -bs=1M -rw=randread

mytest: (g=0): rw=randread, bs=(R) 1024KiB-1024KiB, (W) 1024KiB-1024KiB, (T) 1024KiB-1024KiB, ioengine=psync, iodepth=1
fio-3.16
Starting 1 thread
Jobs: 1 (f=1): [r(1)][100.0%][r=87.0MiB/s][r=87 IOPS][eta 00m:00s]
mytest: (groupid=0, jobs=1): err= 0: pid=11614: Fri Dec 24 14:07:06 2021
read: IOPS=86, BW=86.6MiB/s (90.8MB/s)(1024MiB/11828msec)
clat (usec): min=11068, max=32423, avg=11543.12, stdev=733.86
lat (usec): min=11069, max=32424, avg=11543.85, stdev=733.87
clat percentiles (usec):
| 1.00th=[11076], 5.00th=[11338], 10.00th=[11469], 20.00th=[11469],
| 30.00th=[11469], 40.00th=[11469], 50.00th=[11469], 60.00th=[11600],
| 70.00th=[11600], 80.00th=[11600], 90.00th=[11600], 95.00th=[11600],
| 99.00th=[11600], 99.50th=[11731], 99.90th=[21627], 99.95th=[32375],
| 99.99th=[32375]
bw ( KiB/s): min=83968, max=90112, per=99.94%, avg=88598.26, stdev=1410.46, samples=23
iops : min= 82, max= 88, avg=86.52, stdev= 1.38, samples=23
lat (msec) : 20=99.80%, 50=0.20%
cpu : usr=0.09%, sys=1.40%, ctx=2048, majf=0, minf=256
IO depths : 1=100.0%, 2=0.0%, 4=0.0%, 8=0.0%, 16=0.0%, 32=0.0%, >=64=0.0%
submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
issued rwts: total=1024,0,0,0 short=0,0,0,0 dropped=0,0,0,0
latency : target=0, window=0, percentile=100.00%, depth=1

Run status group 0 (all jobs):
READ: bw=86.6MiB/s (90.8MB/s), 86.6MiB/s-86.6MiB/s (90.8MB/s-90.8MB/s), io=1024MiB (1074MB), run=11828-11828msec

Disk stats (read/write):
mmcblk0: ios=2016/0, merge=0/0, ticks=17397/0, in_queue=17397, util=99.21%

CMD (Randwrite):
sudo fio -filename=/dev/mmcblk0 -direct=1 -numjobs=1 -thread -group_reporting -ioengine=psync -iodepth=1 -size=1G -name=mytest -bs=1M -rw=randwrite

mytest: (g=0): rw=randwrite, bs=(R) 1024KiB-1024KiB, (W) 1024KiB-1024KiB, (T) 1024KiB-1024KiB, ioengine=psync, iodepth=1
fio-3.16
Starting 1 thread
Jobs: 1 (f=1): [w(1)][100.0%][w=50.0MiB/s][w=50 IOPS][eta 00m:00s]
mytest: (groupid=0, jobs=1): err= 0: pid=11668: Fri Dec 24 14:08:36 2021
write: IOPS=39, BW=39.3MiB/s (41.2MB/s)(1024MiB/26059msec); 0 zone resets
clat (msec): min=16, max=118, avg=25.37, stdev=16.34
lat (msec): min=16, max=118, avg=25.44, stdev=16.34
clat percentiles (msec):
| 1.00th=[ 17], 5.00th=[ 20], 10.00th=[ 20], 20.00th=[ 20],
| 30.00th=[ 20], 40.00th=[ 20], 50.00th=[ 20], 60.00th=[ 20],
| 70.00th=[ 21], 80.00th=[ 21], 90.00th=[ 52], 95.00th=[ 75],
| 99.00th=[ 78], 99.50th=[ 104], 99.90th=[ 114], 99.95th=[ 120],
| 99.99th=[ 120]
bw ( KiB/s): min=20480, max=51200, per=99.93%, avg=40211.69, stdev=10498.00, samples=52
iops : min= 20, max= 50, avg=39.27, stdev=10.25, samples=52
lat (msec) : 20=72.95%, 50=16.80%, 100=9.57%, 250=0.68%
cpu : usr=0.41%, sys=0.38%, ctx=1024, majf=0, minf=0
IO depths : 1=100.0%, 2=0.0%, 4=0.0%, 8=0.0%, 16=0.0%, 32=0.0%, >=64=0.0%
submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
issued rwts: total=0,1024,0,0 short=0,0,0,0 dropped=0,0,0,0
latency : target=0, window=0, percentile=100.00%, depth=1

Run status group 0 (all jobs):
WRITE: bw=39.3MiB/s (41.2MB/s), 39.3MiB/s-39.3MiB/s (41.2MB/s-41.2MB/s), io=1024MiB (1074MB), run=26059-26059msec

Disk stats (read/write):
mmcblk0: ios=51/2031, merge=0/0, ticks=84/40061, in_queue=40144, util=99.89%

BR,
Ricky

> Another option that I use frequently is iozone, https://www.iozone.org.
> Here's a command line that I often use for iozone ./iozone -az -i0 -i1 -s 20m -y
> 16k -q 4m -I -f /mnt/sdcard/iozone.tmp -e
>
> [...]
>
> Kind regards
> Uffe
> ------Please consider the environment before printing this e-mail.