Commit d46a857a authored by Stefan Roesch's avatar Stefan Roesch Committed by Yifan Qiao
Browse files

mm: document /sys/class/bdi/<bdi>/min_ratio_fine knob 

mainline inclusion
from mainline-v6.2-rc1
commit eba39236
category: feature
bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAN96I

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=eba39236f18da7a50b6c51df5d902ee72c43e760

--------------------------------

This documents the new /sys/class/bdi/<bdi>/max_ratio_fine knob.

[akpm@linux-foundation.org: fix htmldocs warnings]
Link: https://lkml.kernel.org/r/20221119005215.3052436-21-shr@devkernel.io


Signed-off-by: default avatarStefan Roesch <shr@devkernel.io>
Cc: Chris Mason <clm@meta.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Conflicts:
	Documentation/ABI/testing/sysfs-class-bdi
[Adapt to same document style.]
Signed-off-by: default avatarYifan Qiao <qiaoyifan4@huawei.com>
parent 9450ff8d

Documentation/ABI/testing/sysfs-class-bdi

+11 −0
Original line number Diff line number Diff line
@@ -39,6 +39,17 @@ min_ratio (read-write) 
	percentage of the write-back cache to a particular device.

	For example, this is useful for providing a minimum QoS.



min_ratio_fine (read-write)



	Under normal circumstances each device is given a part of the

	total write-back cache that relates to its current average

	writeout speed in relation to the other devices.



	The 'min_ratio_fine' parameter allows assigning a minimum reserve

	of the write-back cache to a particular device. The value is

	expressed as part of 1 million. For example, this is useful for

	providing a minimum QoS.



max_ratio (read-write)



	Allows limiting a particular device to use not more than the