From: Christoph Hellwig <hch@lst.de>
To: Pankaj Raghav <p.raghav@samsung.com>
Cc: axboe@kernel.dk, hch@lst.de, mcgrof@kernel.org,
gost.dev@samsung.com, linux-block@vger.kernel.org
Subject: Re: [PATCH] brd: improve performance with blk-mq
Date: Mon, 6 Feb 2023 16:50:48 +0100 [thread overview]
Message-ID: <20230206155048.GA13392@lst.de> (raw)
In-Reply-To: <20230203103005.31290-2-p.raghav@samsung.com>
On Fri, Feb 03, 2023 at 04:00:06PM +0530, Pankaj Raghav wrote:
> move to blk-mq based request processing as brd is one of the few drivers
> that still uses submit_bio interface. The changes are pretty trivial
> to start using blk-mq. The performance increases up to 125% for direct IO
> read workloads. There is a slight dip in performance for direct IO write
> workload but considering the general performance gain with blk-mq
> support, it is not a lot.
Can you find out why writes regress, and what improves for reads?
In general blk-mq is doing a lot more work for better batching, but much
of that batching should not matter for a simple ramdisk. So the results
look a little odd to me, and extra numbers and explanations would
really help.
next prev parent reply other threads:[~2023-02-06 15:50 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CGME20230203103122eucas1p161c0f0b674d26e23cf38466d5415420e@eucas1p1.samsung.com>
2023-02-03 10:30 ` [PATCH 0/1] improve brd performance with blk-mq Pankaj Raghav
2023-02-03 10:30 ` [PATCH] brd: improve " Pankaj Raghav
2023-02-06 15:50 ` Christoph Hellwig [this message]
2023-02-06 16:10 ` Pankaj Raghav
2023-02-07 1:43 ` [PATCH 0/1] improve brd " Ming Lei
2023-02-13 5:56 ` Pankaj Raghav
2023-02-13 8:10 ` Ming Lei
2023-02-14 14:48 ` Pankaj Raghav
2023-02-15 6:47 ` Christoph Hellwig
2023-02-15 23:38 ` Jens Axboe
2023-02-15 23:39 ` Jens Axboe
2023-02-17 14:27 ` Pankaj Raghav
2023-02-17 14:40 ` Jens Axboe
2023-02-17 14:52 ` Pankaj Raghav
2023-02-21 21:59 ` Luis Chamberlain
2023-02-21 23:51 ` Jens Axboe
2023-02-22 22:42 ` Luis Chamberlain
2023-02-22 22:47 ` Jens Axboe
2023-02-22 22:54 ` Luis Chamberlain
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