Merge git://git.kernel.org/pub/scm/linux/kernel/git/hirofumi/fatfs-2.6
[linux-2.6] / Documentation / ABI / testing / sysfs-fs-ext4
1 What:           /sys/fs/ext4/<disk>/mb_stats
2 Date:           March 2008
3 Contact:        "Theodore Ts'o" <tytso@mit.edu>
4 Description:
5                  Controls whether the multiblock allocator should
6                  collect statistics, which are shown during the unmount.
7                  1 means to collect statistics, 0 means not to collect
8                  statistics
9
10 What:           /sys/fs/ext4/<disk>/mb_group_prealloc
11 Date:           March 2008
12 Contact:        "Theodore Ts'o" <tytso@mit.edu>
13 Description:
14                 The multiblock allocator will round up allocation
15                 requests to a multiple of this tuning parameter if the
16                 stripe size is not set in the ext4 superblock
17
18 What:           /sys/fs/ext4/<disk>/mb_max_to_scan
19 Date:           March 2008
20 Contact:        "Theodore Ts'o" <tytso@mit.edu>
21 Description:
22                 The maximum number of extents the multiblock allocator
23                 will search to find the best extent
24
25 What:           /sys/fs/ext4/<disk>/mb_min_to_scan
26 Date:           March 2008
27 Contact:        "Theodore Ts'o" <tytso@mit.edu>
28 Description:
29                 The minimum number of extents the multiblock allocator
30                 will search to find the best extent
31
32 What:           /sys/fs/ext4/<disk>/mb_order2_req
33 Date:           March 2008
34 Contact:        "Theodore Ts'o" <tytso@mit.edu>
35 Description:
36                 Tuning parameter which controls the minimum size for 
37                 requests (as a power of 2) where the buddy cache is
38                 used
39
40 What:           /sys/fs/ext4/<disk>/mb_stream_req
41 Date:           March 2008
42 Contact:        "Theodore Ts'o" <tytso@mit.edu>
43 Description:
44                 Files which have fewer blocks than this tunable
45                 parameter will have their blocks allocated out of a
46                 block group specific preallocation pool, so that small
47                 files are packed closely together.  Each large file
48                  will have its blocks allocated out of its own unique
49                  preallocation pool.
50
51 What:           /sys/fs/ext4/<disk>/inode_readahead
52 Date:           March 2008
53 Contact:        "Theodore Ts'o" <tytso@mit.edu>
54 Description:
55                 Tuning parameter which controls the maximum number of
56                 inode table blocks that ext4's inode table readahead
57                 algorithm will pre-read into the buffer cache
58
59 What:           /sys/fs/ext4/<disk>/delayed_allocation_blocks
60 Date:           March 2008
61 Contact:        "Theodore Ts'o" <tytso@mit.edu>
62 Description:
63                 This file is read-only and shows the number of blocks
64                 that are dirty in the page cache, but which do not
65                 have their location in the filesystem allocated yet.
66
67 What:           /sys/fs/ext4/<disk>/lifetime_write_kbytes
68 Date:           March 2008
69 Contact:        "Theodore Ts'o" <tytso@mit.edu>
70 Description:
71                 This file is read-only and shows the number of kilobytes
72                 of data that have been written to this filesystem since it was
73                 created.
74
75 What:           /sys/fs/ext4/<disk>/session_write_kbytes
76 Date:           March 2008
77 Contact:        "Theodore Ts'o" <tytso@mit.edu>
78 Description:
79                 This file is read-only and shows the number of
80                 kilobytes of data that have been written to this
81                 filesystem since it was mounted.