From: Jens Axboe <axboe@kernel.dk>
To: Ming Lei <ming.lei@redhat.com>, Bart Van Assche <bvanassche@acm.org>
Cc: linux-block@vger.kernel.org, Christoph Hellwig <hch@lst.de>,
Jaegeuk Kim <jaegeuk@kernel.org>,
Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>,
Martijn Coenen <maco@android.com>
Subject: Re: [PATCH v2 2/3] loop: Select I/O scheduler 'none' from inside add_disk()
Date: Wed, 4 Aug 2021 11:58:43 -0600 [thread overview]
Message-ID: <7cf7cf6d-bf89-0df2-9aec-6ea7d3efd515@kernel.dk> (raw)
In-Reply-To: <YQn924DHk4axOUso@T590>
On 8/3/21 8:39 PM, Ming Lei wrote:
> On Tue, Aug 03, 2021 at 11:23:03AM -0700, Bart Van Assche wrote:
>> We noticed that the user interface of Android devices becomes very slow
>> under memory pressure. This is because Android uses the zram driver on top
>> of the loop driver for swapping, because under memory pressure the swap
>> code alternates reads and writes quickly, because mq-deadline is the
>> default scheduler for loop devices and because mq-deadline delays writes by
>
> Maybe we can bypass io scheduler always for request with REQ_SWAP, such as:
I don't think that's a good idea at all, what happens if you have a mixed
swap in/out on a rotating drive?
--
Jens Axboe
next prev parent reply other threads:[~2021-08-04 17:58 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-08-03 18:23 [PATCH v2 0/3] Improve loop driver I/O scheduler and QD selection Bart Van Assche
2021-08-03 18:23 ` [PATCH v2 1/3] blk-mq: Introduce the BLK_MQ_F_NO_SCHED_BY_DEFAULT flag Bart Van Assche
2021-08-03 18:23 ` [PATCH v2 2/3] loop: Select I/O scheduler 'none' from inside add_disk() Bart Van Assche
2021-08-04 2:39 ` Ming Lei
2021-08-04 17:43 ` Bart Van Assche
2021-08-05 3:26 ` Ming Lei
2021-08-05 16:49 ` Bart Van Assche
2021-08-04 17:58 ` Jens Axboe [this message]
2021-08-04 5:35 ` Christoph Hellwig
2021-08-04 17:58 ` Bart Van Assche
2021-08-04 18:04 ` Jens Axboe
2021-08-05 6:39 ` Christoph Hellwig
2021-08-03 18:23 ` [PATCH v2 3/3] loop: Add the default_queue_depth kernel module parameter Bart Van Assche
2021-08-04 6:07 ` Greg KH
2021-08-04 17:38 ` Bart Van Assche
2021-08-04 19:33 ` Greg KH
2021-08-05 6:14 ` Chaitanya Kulkarni
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