Whamcloud - gitweb
LU-10948 llite: Revalidate dentries in ll_intent_file_open
We might get a lookup lock in response to our open request and we
definitely want to ensure that our dentry is valid, so it could
actually be matched by dcache code in future operations.
Benchmark results:
This patch can significantly improve open-create + stat on the same
client.
This patch in combination with two others:
https://review.whamcloud.com/#/c/33584
https://review.whamcloud.com/#/c/33585
Improves the 'stat' side of open-create + stat by >10x.
Without patches (master branch commit 26a7abe):
mpirun -np 24 --allow-run-as-root /work/tools/bin/mdtest -n 50000 -d /cache1/out/ -F -C -T -v -w 32k
Operation Max Min Mean Std Dev
--------- --- --- ---- -------
File creation : 3838.205 3838.204 3838.204 0.000
File stat : 33459.289 33459.249 33459.271 0.011
File read : 0.000 0.000 0.000 0.000
File removal : 0.000 0.000 0.000 0.000
Tree creation : 3146.841 3146.841 3146.841 0.000
Tree removal : 0.000 0.000 0.000 0.000
With the three patches:
mpirun -np 24 --allow-run-as-root /work/tools/bin/mdtest -n 50000 -d /cache1/out/ -F -C -T -v -w 32k
SUMMARY rate: (of 1 iterations)
Operation Max Min Mean Std Dev
--------- --- --- ---- -------
File creation : 3822.440 3822.439 3822.440 0.000
File stat : 350620.140 350615.980 350617.193 1.051
File read : 0.000 0.000 0.000 0.000
File removal : 0.000 0.000 0.000 0.000
Tree creation : 2076.727 2076.727 2076.727 0.000
Tree removal : 0.000 0.000 0.000 0.000
Note 33K stats/second vs 350K stats/second.
ls -l time of the mdtest directory is also reduced from 23.5 seconds to
5.8 seconds.
Change-Id: I2cb4f94c0300897adb90cc89425e5cfb1c6fe7af
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Reviewed-on: https://review.whamcloud.com/32157
Reviewed-by: Mike Pershin <mpershin@whamcloud.com>
Tested-by: Jenkins
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>