On Wed, Sep 18, 2019 at 5:47 PM Bart Van Assche <bvanassche@xxxxxxx> wrote: > Combining multiple queues (a) into a single queue (b) that is smaller > than the combined source queues without sacrificing performance is > tricky. We already have one such implementation in the block layer core > and it took considerable time to get that implementation right. See e.g. > blk_mq_sched_mark_restart_hctx() and blk_mq_sched_restart(). Roma, can you please estimate the performance impact in case we switch to it?