Re: [PATCH 0/1] improve brd performance with blk-mq

[Ming Lei <ming.lei@redhat.com>]

On Fri, Feb 03, 2023 at 04:00:05PM +0530, Pankaj Raghav wrote:
> Hi Jens,
>  brd is one of the few block drivers that still uses submit_bio instead
>  of blk-mq framework. The following patch converts brd to start using
>  blk-mq framework. Performance gains are pretty evident for read workloads.
>  The performance numbers are also attached as a part of
>  the commit log.
> 
>  Performance (WD=[read|randread|write|randwrite]):
>  $ modprobe brd rd_size=1048576 rd_nr=1
>  $ echo "none" > /sys/block/ram0/queue/scheduler
>  $ fio --name=<WD>  --ioengine=io_uring --iodepth=64 --rw=<WD> --size=1G \
>    --io_size=20G --loop=4 --cpus_allowed=1 --filename=/dev/ram0 --iodepth=64
>    --direct=[0/1]
> 
>   --direct=0

Can you share perf data on other non-io_uring engine often used? The
thing is that we still have lots of non-io_uring workloads, which can't
be hurt now.


Thanks
Ming