diff options
| author | Tejun Heo <tj@kernel.org> | 2016-05-27 14:34:46 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-07-27 09:47:29 -0700 |
| commit | 400850bd980554801a61737c43f47817adeaa5f5 (patch) | |
| tree | 1475167724e1ae8ec8a250cd4cba62ae34e430fc /fs/nfsd | |
| parent | a519bfe6aeccf9a3555d76b30f9fdefa5b261c0c (diff) | |
writeback: use higher precision calculation in domain_dirty_limits()
commit 62a584fe05eef1f80ed49a286a29328f1a224fb9 upstream.
As vm.dirty_[background_]bytes can't be applied verbatim to multiple
cgroup writeback domains, they get converted to percentages in
domain_dirty_limits() and applied the same way as
vm.dirty_[background]ratio. However, if the specified bytes is lower
than 1% of available memory, the calculated ratios become zero and the
writeback domain gets throttled constantly.
Fix it by using per-PAGE_SIZE instead of percentage for ratio
calculations. Also, the updated DIV_ROUND_UP() usages now should
yield 1/4096 (0.0244%) as the minimum ratio as long as the specified
bytes are above zero.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Miao Xie <miaoxie@huawei.com>
Link: http://lkml.kernel.org/g/57333E75.3080309@huawei.com
Fixes: 9fc3a43e1757 ("writeback: separate out domain_dirty_limits()")
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Adjusted comment based on Jan's suggestion.
Signed-off-by: Jens Axboe <axboe@fb.com>
Diffstat (limited to 'fs/nfsd')
0 files changed, 0 insertions, 0 deletions