From 54790f30fea74247e2f38b4a632ee3dc2fe42d86 Mon Sep 17 00:00:00 2001 From: Stefan Roesch Date: Fri, 18 Nov 2022 16:52:12 -0800 Subject: [PATCH] mm: document /sys/class/bdi//max_ratio_fine knob This documents the new /sys/class/bdi//max_ratio_fine knob. [akpm@linux-foundation.org: fix htmldocs warnings] Link: https://lkml.kernel.org/r/20221119005215.3052436-18-shr@devkernel.io Signed-off-by: Stefan Roesch Cc: Chris Mason Cc: Jens Axboe Signed-off-by: Andrew Morton --- Documentation/ABI/testing/sysfs-class-bdi | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-class-bdi b/Documentation/ABI/testing/sysfs-class-bdi index a9a2f588a2b7..e9c584db316f 100644 --- a/Documentation/ABI/testing/sysfs-class-bdi +++ b/Documentation/ABI/testing/sysfs-class-bdi @@ -57,6 +57,19 @@ Description: (read-write) +What: /sys/class/bdi//max_ratio_fine +Date: November 2022 +Contact: Stefan Roesch +Description: + Allows limiting a particular device to use not more than the + given value of the write-back cache. The value is given as part + of 1 million. This is useful in situations where we want to avoid + one device taking all or most of the write-back cache. For example + in case of an NFS mount that is prone to get stuck, or a FUSE mount + which cannot be trusted to play fair. + + (read-write) + What: /sys/class/bdi//min_bytes Date: October 2022 Contact: Stefan Roesch