Hi Song,
On 5/27/21 2:14 PM, Song Liu wrote:
Could you point the place where md enables iostats before the set?
I can't find relevant code for it.
Before this set, we did not set QUEUE_FLAG_IO_STAT, and we didn't
check blk_queue_io_stat() either. So even with /sys/block/mdX/queue/iostats
of 0, we still get iostats for the md device. By setting QUEUE_FLAG_IO_STAT
with the patch, the users still get iostats working by default.
I am okay with enable it by default, though users need to know the
parameter given it affects the performance.
Thanks,
Guoqing
