Re: [PATCH] Block SQ/MQ Request Priority

From: Jens Axboe
Date: Tue Apr 04 2017 - 17:40:44 EST


On 04/04/2017 09:25 AM, adam.manzanares@xxxxxxx wrote:
> From: Adam Manzanares <adam.manzanares@xxxxxxx>
>
> In 4.10 I introduced a patch that associates the ioc priority with
> each request in the block layer. This work was done in the single queue
> block layer code. This patch unifies ioc priority to request mapping across
> the single/multi queue block layers.
>
> I have tested this patch with the null block device driver with the following
> parameters.
>
> null_blk queue_mode=2 irqmode=0 use_per_node_hctx=1 nr_devices=1
>
> I have not seen a performance regression with this patch and I would appreciate
> any feedback or additional testing.
>
> I have also verified that io priorities are passed to the device when using
> the SQ and MQ path to a SATA HDD that supports io priorities.

Applied, with an updated subject line, it didn't really describe what
the patch does. Thanks.

--
Jens Axboe