On 10/10/2017 14:45, Ming Lei wrote:
Hi John,
All change in V6.2 is blk-mq/scsi-mq only, which shouldn't
affect non SCSI_MQ, so I suggest you to compare the perf
between deadline and mq-deadline, like Johannes mentioned.
>
> V6.2 series with default SCSI_MQ
> read, rw, write IOPS
> 700K, 130K/128K, 640K
If possible, could you provide your fio script and log on both
non SCSI_MQ(deadline) and SCSI_MQ(mq_deadline)? Maybe some clues
can be figured out.
Also, I just put another patch on V6.2 branch, which may improve
a bit too. You may try that in your test.
https://github.com/ming1/linux/commit/e31e2eec46c9b5ae7cfa181e9b77adad2c6a97ce
-- Ming .
Hi Ming Lei,
OK, I have tested deadline vs mq-deadline for your v6.2 branch and
4.12-rc2. Unfortunately I don't have time now to test your experimental
patches.
4.14-rc2 without default SCSI_MQ, deadline scheduler
read, rw, write IOPS
920K, 115K/115K, 806K
4.14-rc2 with default SCSI_MQ, mq-deadline scheduler
read, rw, write IOPS
280K, 99K/99K, 300K
V6.2 series without default SCSI_MQ, deadline scheduler
read, rw, write IOPS
919K, 117K/117K, 806K
V6.2 series with default SCSI_MQ, mq-deadline scheduler
read, rw, write IOPS
688K, 128K/128K, 630K
I think that the non-mq results look a bit more sensible - that is,
consistent results.
Here's my script sample:
[global]
rw=rW
direct=1
ioengine=libaio
iodepth=2048
numjobs=1
bs=4k
;size=10240000m
;zero_buffers=1
group_reporting=1
group_reporting=1
;ioscheduler=noop
cpumask=0xff
;cpus_allowed=0-3
;gtod_reduce=1
;iodepth_batch=2
;iodepth_batch_complete=2
runtime=100000000
;thread
loops = 10000
[job1]
filename=/dev/sdb:
[job1]
filename=/dev/sdc:
[job1]
filename=/dev/sdd:
[job1]
filename=/dev/sde:
[job1]
filename=/dev/sdf:
[job1]
filename=/dev/sdg:
John