summaryrefslogtreecommitdiffstats
path: root/Documentation/filesystems
diff options
context:
space:
mode:
authorEric Sandeen <sandeen@redhat.com>2010-04-30 11:09:34 -0500
committerJan Kara <jack@suse.cz>2010-05-21 19:30:41 +0200
commit0636c73ee7b129f77f577aaaefc8dde057be6d18 (patch)
tree6cf9dba3119f9ec6fa346572c8a5bd693828bf45 /Documentation/filesystems
parentdde9588853b1bde542eab247f8838c472806688f (diff)
downloadlinux-0636c73ee7b129f77f577aaaefc8dde057be6d18.tar.bz2
ext3: make barrier options consistent with ext4
ext4 was updated to accept barrier/nobarrier mount options in addition to the older barrier=0/1. The barrier story is complex enough, we should help people by making the options the same at least, even if the defaults are different. This patch allows the barrier/nobarrier mount options for ext3, while keeping nobarrier the default. It also unconditionally displays barrier status in show_options, and prints a message at mount time if barriers are not enabled, just as ext4 does. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Jan Kara <jack@suse.cz>
Diffstat (limited to 'Documentation/filesystems')
-rw-r--r--Documentation/filesystems/ext3.txt15
1 files changed, 13 insertions, 2 deletions
diff --git a/Documentation/filesystems/ext3.txt b/Documentation/filesystems/ext3.txt
index 867c5b50cb42..272f80d5f966 100644
--- a/Documentation/filesystems/ext3.txt
+++ b/Documentation/filesystems/ext3.txt
@@ -59,8 +59,19 @@ commit=nrsec (*) Ext3 can be told to sync all its data and metadata
Setting it to very large values will improve
performance.
-barrier=1 This enables/disables barriers. barrier=0 disables
- it, barrier=1 enables it.
+barrier=<0(*)|1> This enables/disables the use of write barriers in
+barrier the jbd code. barrier=0 disables, barrier=1 enables.
+nobarrier (*) This also requires an IO stack which can support
+ barriers, and if jbd gets an error on a barrier
+ write, it will disable again with a warning.
+ Write barriers enforce proper on-disk ordering
+ of journal commits, making volatile disk write caches
+ safe to use, at some performance penalty. If
+ your disks are battery-backed in one way or another,
+ disabling barriers may safely improve performance.
+ The mount options "barrier" and "nobarrier" can
+ also be used to enable or disable barriers, for
+ consistency with other ext3 mount options.
orlov (*) This enables the new Orlov block allocator. It is
enabled by default.