On Thu, Mar 14, 2024 at 11:20 AM <junxiao.bi@xxxxxxxxxx> wrote: > [...] > >> > >> This patch eliminated the benefit of blk_plug, i think it will not be > >> good for IO performance perspective? > > > > There is only one daemon thread, so IO should not be handled here as > > much as possible. The IO should be handled by the thread that is > > submitting the IO, and let daemon to hanldle the case that IO failed or > > can't be submitted at that time. raid5 can have multiple threads calling handle_stripe(). See raid5_do_work(). Only chunk_aligned_read() can be handled in raid5_make_request. > > I am not sure how much it will impact regarding drop the blk_plug. > > Song, what's your take on this? I think we need to evaluate the impact of (removing) blk_plug. We had some performance regressions related to blk_plug a couple years ago. Thanks, Song