[Devel] Re: [PATCH] cfq: async queue allocation per priority

[Jens Axboe]

On Wed, Jul 18 2007, Vasily Tarasov wrote:
> Jens, I think the last patch, that makes queues allocation per priority,
> has a problem.
> 
> If we have two processes with different ioprio_class, but the same
> ioprio_data, their async requests will fall into the same queue. I guess
> such behavior is not expected, because it's not right to put real-time
> requests and best-effort requests in the same queue.
> 
> The attached patch fixes the problem by introducing additional *cfqq
> fields on cfqd, pointing to per-(class,priority) async queues.

Ugh yes. I'm pretty tempted just to reinstate the cfqq hash again, it
used to be a clean up but now the it's not stacking up so well.

-- 
Jens Axboe