On Tue, Oct 17, 2017 at 01:04:16PM +0800, Ming Lei wrote: > Hi Jens, > > The 1st patch runs idle hctx after dealy in scsi_mq_get_budget(), > so that we can keep same behaviour with before, and it can be > thought as a fix. > > The 2nd patch cleans up RESTART, and removes handling for TAG_SHARED > from current blk-mq's RESTART mechanism because SCSI_MQ can covers its > restart by itself, so that no need to handle TAG_SHARED in blk-mq > RESTART. And >20% IOPS boost is observed in my rand read test over > scsi_debug. > > John, please test this two patches and see if it may improve your SAS > IO performance, and you can find the two patches in the following branch: > > https://github.com/ming1/linux/commits/blk_mq_improve_restart_V1 Forget to mention, you need to either pull the above branch directly or apply the two patches against for-next branch of Jens' block tree: git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git #for-next -- Ming
