Whamcloud - gitweb
LU-12043 llite: don't miss every first stride page
Whenever we need skip some pages for stride io read, we
will calculate next start page index, however, this page
index is skipped every time, because loop start from index + 1
Testing command: iozone -w -c -i 5 -t1 -j 2 -s 100m -r 1m -F data
Without patch: 587384.69 kB/sec
read write
pages per rpc rpcs % cum % | rpcs % cum %
1: 16 19 19 | 0 0 0
2: 0 0 19 | 0 0 0
4: 0 0 19 | 0 0 0
8: 0 0 19 | 0 0 0
16: 0 0 19 | 0 0 0
32: 0 0 19 | 0 0 0
64: 0 0 19 | 0 0 0
128: 0 0 19 | 0 0 0
256: 0 0 19 | 0 0 0
512: 22 26 46 | 0 0 0
1024: 44 53 100 | 0 0 0
With patch: 744635.56 kB/sec
read write
pages per rpc rpcs % cum % | rpcs % cum %
1: 0 0 0 | 0 0 0
2: 0 0 0 | 0 0 0
4: 0 0 0 | 0 0 0
8: 0 0 0 | 0 0 0
16: 0 0 0 | 0 0 0
32: 0 0 0 | 0 0 0
64: 0 0 0 | 0 0 0
128: 0 0 0 | 0 0 0
256: 0 0 0 | 0 0 0
512: 8 13 13 | 0 0 0
1024: 50 86 100 | 0 0 0
We get better performances ~27% up here, and all 1 page RPC
disappear.
Change-Id: I126674cbe15197f0abdff256fdde3fc0c49c6898
Signed-off-by: Wang Shilong <wshilong@ddn.com>
Reviewed-on: https://review.whamcloud.com/35216
Tested-by: jenkins <devops@whamcloud.com>
Reviewed-by: Li Xi <lixi@ddn.com>
Reviewed-by: Patrick Farrell <pfarrell@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>
git://git.whamcloud.com / fs / lustre-release.git / commit