[PATCH] vm: Document that setting vfs_cache_pressure to 0 isn't a good idea

[PATCH] vm: Document that setting vfs_cache_pressure to 0 isn't a good idea

[Jan Kara]

Reported-by: Christian Thaeter <ct@pipapo.org>
Signed-off-by: Jan Kara <jack@suse.cz>
---
 Documentation/sysctl/vm.txt |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)

 Andrew, would you merge this please? Thanks.

diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt
index c4de635..76e8671 100644
--- a/Documentation/sysctl/vm.txt
+++ b/Documentation/sysctl/vm.txt
@@ -585,7 +585,9 @@ caching of directory and inode objects.
 At the default value of vfs_cache_pressure=100 the kernel will attempt to
 reclaim dentries and inodes at a "fair" rate with respect to pagecache and
 swapcache reclaim.  Decreasing vfs_cache_pressure causes the kernel to prefer
-to retain dentry and inode caches.  Increasing vfs_cache_pressure beyond 100
+to retain dentry and inode caches. When vfs_cache_pressure=0, the kernel will
+never reclaim dentries and inodes due to memory pressure and this can easily
+lead to out-of-memory conditions. Increasing vfs_cache_pressure beyond 100
 causes the kernel to prefer to reclaim dentries and inodes.
 
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1.6.0.2