Re: [PATCH 1/3] nvme/pci: Start request after doorbell ring

Christoph Hellwig
2017-12-29T09:44:40Z

On Mon, Dec 25, 2017 at 12:12:52PM +0200, Sagi Grimberg wrote:
>
>>> But that does bring up the fact if we should always be doing the
>>> nvme_process_cq(nvmeq) after IO submission. For direct/hipri IO,
>>> maybe it's better to make the submission path faster and skip it?
>>
>> Yes, I am okay to remove the opprotunistic nvme_process_cq in the
>> submission path. Even under deeply queued IO, I've not seen this provide
>> any measurable benefit.
>
> +100 for removing it. Never really understood why it gets us anything...

Yes, we should get rid of it.