diff options
author | Eric Sandeen <sandeen@redhat.com> | 2010-04-30 12:09:34 -0400 |
---|---|---|
committer | Jan Kara <jack@suse.cz> | 2010-05-21 13:30:41 -0400 |
commit | 0636c73ee7b129f77f577aaaefc8dde057be6d18 (patch) | |
tree | 6cf9dba3119f9ec6fa346572c8a5bd693828bf45 /Documentation/filesystems/ext3.txt | |
parent | dde9588853b1bde542eab247f8838c472806688f (diff) |
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/ext3.txt')
-rw-r--r-- | Documentation/filesystems/ext3.txt | 15 |
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 | |||
59 | Setting it to very large values will improve | 59 | Setting it to very large values will improve |
60 | performance. | 60 | performance. |
61 | 61 | ||
62 | barrier=1 This enables/disables barriers. barrier=0 disables | 62 | barrier=<0(*)|1> This enables/disables the use of write barriers in |
63 | it, barrier=1 enables it. | 63 | barrier the jbd code. barrier=0 disables, barrier=1 enables. |
64 | nobarrier (*) This also requires an IO stack which can support | ||
65 | barriers, and if jbd gets an error on a barrier | ||
66 | write, it will disable again with a warning. | ||
67 | Write barriers enforce proper on-disk ordering | ||
68 | of journal commits, making volatile disk write caches | ||
69 | safe to use, at some performance penalty. If | ||
70 | your disks are battery-backed in one way or another, | ||
71 | disabling barriers may safely improve performance. | ||
72 | The mount options "barrier" and "nobarrier" can | ||
73 | also be used to enable or disable barriers, for | ||
74 | consistency with other ext3 mount options. | ||
64 | 75 | ||
65 | orlov (*) This enables the new Orlov block allocator. It is | 76 | orlov (*) This enables the new Orlov block allocator. It is |
66 | enabled by default. | 77 | enabled by default. |