diff options
| author |   NeilBrown <neilb@suse.de> | 2012-07-31 09:08:14 +0200 |
|---|---|---|
| committer |   Jens Axboe <axboe@kernel.dk> | 2012-07-31 09:08:14 +0200 |
| commit | 0021b7bc045e4b0b85d8c53614342aaf84ca96a5 (patch) | |
| tree | 1432761eec4c49bbacea55df083e73599e18ea1c /drivers/md/md.h | |
| parent | block/nbd: micro-optimization in nbd request completion (diff) | |
| download | linux-dev-0021b7bc045e4b0b85d8c53614342aaf84ca96a5.tar.xz linux-dev-0021b7bc045e4b0b85d8c53614342aaf84ca96a5.zip | |
md: remove plug_cnt feature of plugging.
This seemed like a good idea at the time, but after further thought I
cannot see it making a difference other than very occasionally and
testing to try to exercise the case it is most likely to help did not
show any performance difference by removing it.
So remove the counting of active plugs and allow 'pending writes' to
be activated at any time, not just when no plugs are active.
This is only relevant when there is a write-intent bitmap, and the
updating of the bitmap will likely introduce enough delay that
the single-threading of bitmap updates will be enough to collect large
numbers of updates together.
Removing this will make it easier to centralise the unplug code, and
will clear the other for other unplug enhancements which have a
measurable effect.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers/md/md.h')
| -rw-r--r-- | drivers/md/md.h | 3 |
1 files changed, 0 insertions, 3 deletions
diff --git a/drivers/md/md.h b/drivers/md/md.h index 7b4a3c318cae..91786c46b85c 100644 --- a/drivers/md/md.h +++ b/drivers/md/md.h @@ -266,9 +266,6 @@ struct mddev { int new_chunk_sectors; int reshape_backwards; - atomic_t plug_cnt; /* If device is expecting - * more bios soon. - */ struct md_thread *thread; /* management thread */ struct md_thread *sync_thread; /* doing resync or reconstruct */ sector_t curr_resync; /* last block scheduled */ |