From: Jens Axboe <axboe@kernel.dk>
To: "muraliraja.muniraju" <muraliraja.muniraju@rubrik.com>
Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] Adding multiple workers to the loop device.
Date: Thu, 23 Jan 2020 12:02:04 -0700 [thread overview]
Message-ID: <2571ea8b-9d64-b0c1-0311-be0a69cf1320@kernel.dk> (raw)
In-Reply-To: <88d16046-f9aa-d5e8-1b1c-7c3ff9516290@kernel.dk>
On 1/23/20 11:59 AM, Jens Axboe wrote:
> On 1/21/20 12:25 PM, muraliraja.muniraju wrote:
>> Current loop device implementation has a single kthread worker and
>> drains one request at a time to completion. If the underneath device is
>> slow then this reduces the concurrency significantly. To help in these
>> cases, adding multiple loop workers increases the concurrency. Also to
>> retain the old behaviour the default number of loop workers is 1 and can
>> be tuned via the ioctl.
>
> Have you considered using blk-mq for this? Right now loop just does
> some basic checks and then queues for a thread. If you bump nr_hw_queues
> up (provide a parameter for that) and set BLK_MQ_F_BLOCKING in the
> tag flags, then that might be a more viable approach for handling this.
Then you could also dump cmd->work, which would shrink loop_cmd by more
than 1/3rd.
--
Jens Axboe
next prev parent reply other threads:[~2020-01-23 19:02 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-21 19:25 muraliraja.muniraju
2020-01-23 18:59 ` Jens Axboe
2020-01-23 19:02 ` Jens Axboe [this message]
2020-01-23 19:25 ` Muraliraja Muniraju
2020-01-23 19:29 ` Jens Axboe
2020-01-23 19:45 ` Muraliraja Muniraju
[not found] <DM6PR04MB5754D8E261B4200AA62D442D860D0@DM6PR04MB5754.namprd04.prod.outlook.com>
2020-01-21 20:01 ` muraliraja.muniraju
2020-01-21 20:03 ` muraliraja.muniraju
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