Re: [patch]blk-mq: blk_mq_tag_to_rq should handle flush request

Christoph Hellwig
2014-06-04T15:10:24Z

On Wed, Jun 04, 2014 at 09:08:12AM -0600, Jens Axboe wrote:
> >The performance regression is caused by "blk-mq: avoid code
> >duplication", but I don't really understand why yet.
>
> Gah, looks like this one dropped the tag idling. I bet that is why.

Ah, thanks. It's indeed exactly the same sort of slow down I bisected
back then, this should have rung a bell instead of keeping me occupied
for hours..