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| author | Li Feng | 2018-11-01 11:38:07 +0100 |
|---|---|---|
| committer | Fam Zheng | 2019-01-09 02:38:34 +0100 |
| commit | 2916405a11d3119cfa367ea73d66e22ea8118382 (patch) | |
| tree | 7a8b3d13cd48bbafde0c95b9bbbff196428f3ded /hw/usb/dev-hub.c | |
| parent | Merge remote-tracking branch 'remotes/kraxel/tags/usb-20190108-pull-request' ... (diff) | |
| download | qemu-2916405a11d3119cfa367ea73d66e22ea8118382.tar.gz qemu-2916405a11d3119cfa367ea73d66e22ea8118382.tar.xz qemu-2916405a11d3119cfa367ea73d66e22ea8118382.zip | |
block/nvme: optimize the performance of nvme driver based on vfio-pci
When the IO size is larger than 2 pages, we move the the pointer one by
one in the pagelist, this is inefficient.
This is a simple benchmark result:
Before:
$ qemu-io -c 'write 0 1G' nvme://0000:00:04.0/1
wrote 1073741824/1073741824 bytes at offset 0
1 GiB, 1 ops; 0:00:02.41 (424.504 MiB/sec and 0.4146 ops/sec)
$ qemu-io -c 'read 0 1G' nvme://0000:00:04.0/1
read 1073741824/1073741824 bytes at offset 0
1 GiB, 1 ops; 0:00:02.03 (503.055 MiB/sec and 0.4913 ops/sec)
After:
$ qemu-io -c 'write 0 1G' nvme://0000:00:04.0/1
wrote 1073741824/1073741824 bytes at offset 0
1 GiB, 1 ops; 0:00:02.17 (471.517 MiB/sec and 0.4605 ops/sec)
$ qemu-io -c 'read 0 1G' nvme://0000:00:04.0/1
read 1073741824/1073741824 bytes at offset 0
1 GiB, 1 ops; 0:00:01.94 (526.770 MiB/sec and 0.5144 ops/sec)
Signed-off-by: Li Feng <lifeng1519@gmail.com>
Message-Id: <20181101103807.25862-1-lifeng1519@gmail.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Diffstat (limited to 'hw/usb/dev-hub.c')
0 files changed, 0 insertions, 0 deletions