Re: [PATCH] range-bw: Another I/O scheduling policy of dm-ioband supporting the predicable I/O bandwidth (range bandwidth)

[Dong-Jae Kang <baramsori72@gmail.com>]

Hi, Ryo

I released bug-fixed range-bw(V1) controller several minutes ago

Although several WARNINGs of checkpatch are remained,
but patch file was strictly checked by checkpatch.pl
It was very time-consuming job :)
Thank you for your advice

>>
>> > I used fio 1.22. The below is a script which I actually ran.
>> >
>> >  #!/bin/sh
>> >  dev1=/dev/sdb4 # SATA disk
>> >  echo "0 $(sudo blockdev --getsize $dev1) ioband $dev1 share2 0 0
>> >    cgroup range-bw 0" | sudo dmsetup create ioband1
>> >
>> >  arg="--time_based --runtime=10 --ioengine=libaio --iodepth=50 \
>> >       --direct=1 --norandommap"
>> >
>> >  dmsetup message ioband1 0 attach 2
>> >  dmsetup message ioband1 0 attach 3
>> >  dmsetup message ioband1 0 min-bw 2:100
>> >  dmsetup message ioband1 0 max-bw 2:100
>> >  dmsetup message ioband1 0 min-bw 3:200
>> >  dmsetup message ioband1 0 max-bw 3:200
>>
>> I recommend it is better to use different value in min-bw and max-bw
>> because its concept is to support range-bw with the minimum
>> guaranteeing and maximum limitation.
>> exampe - min-bw : 1024 / max-bw : 3072
>>
>> >  echo $$ > /cgroup/grp1/tasks
>> >  fio $arg --rw=randread --name=grp1 --filename=/dev/mapper/ioband1 \
>> >          --output=r2-1.log &
>> >  echo $$ > /cgroup/grp2/tasks
>> >  fio $arg --rw=randread --name=grp2 --filename=/dev/mapper/ioband1 \
>> >          --output=r2-2.log &
>> >  wait

after bug-fix,I evaluated range-bw according to your configuration and
test environment
the result is in new relesed range-bw mail, [PATCH 0/2]
and more detailed documentation is also available and it can be
referred in [PATCH 1/2]

Ryo,
can you check the result ?

> bio-cgroup is renamed to bklio-cgroup. :)
> I don't clearly understand about range-bw but I think that you don't
> need to consider to support them and it should be taken care of by
> blkio-cgroup and the common part of dm-ioband, not the policy
> implementation. Do you have any problems with AIO or delayed write?

if you are interested in range-bw, more information is available to you
and any questions and comments about range-bw is always welcom.  :)

Ryo,
blkio-cgroup can be applied to dm-ioband ver1.10.3 without modification?
I didn't check blkio-cgroup yet.

Thank you
>> --
>> Best Regards,
>> Dong-Jae Kang
>



-- 
Best Regards,
Dong-Jae Kang