[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <87mxamjyvg.fsf@rustcorp.com.au>
Date: Wed, 21 Dec 2011 15:38:03 +1030
From: Rusty Russell <rusty@...tcorp.com.au>
To: Minchan Kim <minchan@...nel.org>
Cc: Chris Wright <chrisw@...s-sol.org>, Jens Axboe <axboe@...nel.dk>,
Stefan Hajnoczi <stefanha@...ux.vnet.ibm.com>,
kvm@...r.kernel.org, linux-kernel@...r.kernel.org,
Christoph Hellwig <hch@...radead.org>,
Minchan Kim <minchan@...nel.org>
Subject: Re: [PATCH 0/6][RFC] virtio-blk: Change I/O path from request to BIO
On Wed, 21 Dec 2011 10:00:48 +0900, Minchan Kim <minchan@...nel.org> wrote:
> This patch is follow-up of Christohp Hellwig's work
> [RFC: ->make_request support for virtio-blk].
> http://thread.gmane.org/gmane.linux.kernel/1199763
>
> Quote from hch
> "This patchset allows the virtio-blk driver to support much higher IOP
> rates which can be driven out of modern PCI-e flash devices. At this
> point it really is just a RFC due to various issues."
>
> I fixed race bug and add batch I/O for enhancing sequential I/O,
> FLUSH/FUA emulation.
>
> I tested this patch on fusion I/O device by aio-stress.
> Result is following as.
>
> Benchmark : aio-stress (64 thread, test file size 512M, 8K io per IO, O_DIRECT write)
> Environment: 8 socket - 8 core, 2533.372Hz, Fusion IO 320G storage
> Test repeated by 20 times
> Guest I/O scheduler : CFQ
> Host I/O scheduler : NOOP
>
> Request BIO(patch 1-4) BIO-batch(patch 1-6)
> (MB/s) stddev (MB/s) stddev (MB/s) stddev
> w 737.820 4.063 613.735 31.605 730.288 24.854
> rw 208.754 20.450 314.630 37.352 317.831 41.719
> r 770.974 2.340 347.483 51.370 750.324 8.280
> rr 250.391 16.910 350.053 29.986 325.976 24.846
So, you dropped w and r down 2%, but rw and rr up 40%.
If I knew what the various rows were, I'd have something intelligent to
say, I'm sure :)
I can find the source to aio-stress, but no obvious clues.
Help!
Rusty.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists