From: Jens Axboe <axboe@fb.com>
To: Christoph Hellwig <hch@lst.de>
Cc: <linux-kernel@vger.kernel.org>
Subject: Re: blk-mq: refactor request allocation
Date: Wed, 28 May 2014 09:47:23 -0600 [thread overview]
Message-ID: <5386050B.4000900@fb.com> (raw)
In-Reply-To: <20140528051919.GA21566@lst.de>
On 2014-05-27 23:19, Christoph Hellwig wrote:
> On Tue, May 27, 2014 at 02:58:08PM -0600, Jens Axboe wrote:
>> On 05/27/2014 12:59 PM, Christoph Hellwig wrote:
>>> This series streamlines the request allocation path.
>>>
>>
>> Series looks innocuous enough to me, but it's about a 1.5% performance
>> drop here with an actual device. These tests are very stable, anything
>> over ~0.1% is definitely outside of noise. I repeated and rebooted a few
>> times and tested both, it's persistent. No smoking guns in the profile.
>
> Can you do a bisect to narrow it down to one of the patches?
Did bisect and even one-by-one, and now it doesn't show up of course.
The nvme branch was rebased on top of a new base since yesterday, so it
could just be layout weirdness from the previous one.
So I think we can call it fine, I'll apply it.
--
Jens Axboe
prev parent reply other threads:[~2014-05-28 15:47 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-05-27 18:59 blk-mq: refactor request allocation Christoph Hellwig
2014-05-27 18:59 ` [PATCH 1/5] blk-mq: merge blk_mq_alloc_reserved_request into blk_mq_alloc_request Christoph Hellwig
2014-05-27 18:59 ` [PATCH 2/5] blk-mq: initialize request in __blk_mq_alloc_request Christoph Hellwig
2014-05-27 18:59 ` [PATCH 3/5] blk-mq: remove blk_mq_wait_for_tags Christoph Hellwig
2014-05-27 18:59 ` [PATCH 4/5] blk-mq: do not use blk_mq_alloc_request_pinned in blk_mq_map_request Christoph Hellwig
2014-05-27 18:59 ` [PATCH 5/5] blk-mq: remove blk_mq_alloc_request_pinned Christoph Hellwig
2014-05-27 20:58 ` blk-mq: refactor request allocation Jens Axboe
2014-05-28 5:19 ` Christoph Hellwig
2014-05-28 14:20 ` Jens Axboe
2014-05-28 15:47 ` Jens Axboe [this message]
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