Subject: Re: [PATCH V2 2/2] blk-mq: immediately dispatch big size request
To: Shaohua Li <shli@fb.com>, Christoph Hellwig <hch@infradead.org>
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 <20161104000954.GA10266@infradead.org>
 <20161104001353.GA58908@omida-mbp.local.dhcp.thefacebook.com>
CC: <linux-block@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
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From: Jens Axboe <axboe@fb.com>
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Date: Thu, 3 Nov 2016 22:00:58 -0600
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On 11/03/2016 06:13 PM, Shaohua Li wrote:
> On Thu, Nov 03, 2016 at 05:09:54PM -0700, Christoph Hellwig wrote:
>> On Thu, Nov 03, 2016 at 05:03:54PM -0700, Shaohua Li wrote:
>>> This is corresponding part for blk-mq. Disk with multiple hardware
>>> queues doesn't need this as we only hold 1 request at most.
>>
>> Any reason you only do this for the SQ and not the MQ case?
>
> Right above:
> Disk with multiple hardware queues doesn't need this as we only hold 1
> request at most.

I've applied 1-2 for 4.10, but we probably should look into unifying
those parts of sq and mq in general. For instance, it doesn't seem to
make a lot of sense why we'd depth limit sq and not mq.

-- 
Jens Axboe