path: root/Documentation/filesystems/tmpfs.txt
diff options
authorHugh Dickins <hugh@veritas.com>2005-06-21 17:15:04 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-06-21 18:46:18 -0700
commit0edd73b33426df61b1d8a0a50d1f2ec097500abb (patch)
treeedbc6d9b53ebd107befaf53fbefaaf1a55244273 /Documentation/filesystems/tmpfs.txt
parent65ed0b337bd2b47097cf6c772f024772513b7b0d (diff)
[PATCH] shmem: restore superblock info
To improve shmem scalability, we allowed tmpfs instances which don't need their blocks or inodes limited not to count them, and not to allocate any sbinfo. Which was okay when the only use for the sbinfo was accounting blocks and inodes; but since then a couple of unrelated projects extending tmpfs want to store other data in the sbinfo. Whether either extension reaches mainline is beside the point: I'm guilty of a bad design decision, and should restore sbinfo to make any such future extensions easier. So, once again allocate a shmem_sb_info for every shmem/tmpfs instance, and now let max_blocks 0 indicate unlimited blocks, and max_inodes 0 unlimited inodes. Brent Casavant verified (many months ago) that this does not perceptibly impact the scalability (since the unlimited sbinfo cacheline is repeatedly accessed but only once dirtied). And merge shmem_set_size into its sole caller shmem_remount_fs. Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'Documentation/filesystems/tmpfs.txt')
1 files changed, 3 insertions, 3 deletions
diff --git a/Documentation/filesystems/tmpfs.txt b/Documentation/filesystems/tmpfs.txt
index 417e3095fe39..0d783c504ead 100644
--- a/Documentation/filesystems/tmpfs.txt
+++ b/Documentation/filesystems/tmpfs.txt
@@ -71,8 +71,8 @@ can be changed on remount. The size parameter also accepts a suffix %
to limit this tmpfs instance to that percentage of your physical RAM:
the default, when neither size nor nr_blocks is specified, is size=50%
-If both nr_blocks (or size) and nr_inodes are set to 0, neither blocks
-nor inodes will be limited in that instance. It is generally unwise to
+If nr_blocks=0 (or size=0), blocks will not be limited in that instance;
+if nr_inodes=0, inodes will not be limited. It is generally unwise to
mount with such options, since it allows any user with write access to
use up all the memory on the machine; but enhances the scalability of
that instance in a system with many cpus making intensive use of it.
@@ -97,4 +97,4 @@ RAM/SWAP in 10240 inodes and it is only accessible by root.
Christoph Rohland <cr@sap.com>, 1.12.01
- Hugh Dickins <hugh@veritas.com>, 01 September 2004
+ Hugh Dickins <hugh@veritas.com>, 13 March 2005