Hi Rusty, On Wed, Dec 21, 2011 at 03:38:03PM +1030, Rusty Russell wrote: > On Wed, 21 Dec 2011 10:00:48 +0900, Minchan Kim <minchan@xxxxxxxxxx> 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 :) Sorry for missing that. w: Sequential Write rw: Random Write r: Sequential Read rr: Random Read > > I can find the source to aio-stress, but no obvious clues. > > Help! > Rusty. -- Kind regards, Minchan Kim -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
