6f9524e9e1
Add documentation for mount options and ioctls to Documentation/filesystem/ext4.txt, which has not been udpated for some time. Also add for ext4 sysfs tunables to the Documentation/ABI/testing/sysfs-fs-ext4 file, and fix a few typographical errors in that file. https://bugzilla.kernel.org/show_bug.cgi?id=9423 Signed-off-by: Lukas Czerner <lczerner@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
99 lines
3.2 KiB
Plaintext
99 lines
3.2 KiB
Plaintext
What: /sys/fs/ext4/<disk>/mb_stats
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Date: March 2008
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Contact: "Theodore Ts'o" <tytso@mit.edu>
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Description:
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Controls whether the multiblock allocator should
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collect statistics, which are shown during the unmount.
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1 means to collect statistics, 0 means not to collect
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statistics
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What: /sys/fs/ext4/<disk>/mb_group_prealloc
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Date: March 2008
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Contact: "Theodore Ts'o" <tytso@mit.edu>
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Description:
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The multiblock allocator will round up allocation
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requests to a multiple of this tuning parameter if the
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stripe size is not set in the ext4 superblock
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What: /sys/fs/ext4/<disk>/mb_max_to_scan
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Date: March 2008
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Contact: "Theodore Ts'o" <tytso@mit.edu>
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Description:
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The maximum number of extents the multiblock allocator
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will search to find the best extent
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What: /sys/fs/ext4/<disk>/mb_min_to_scan
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Date: March 2008
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Contact: "Theodore Ts'o" <tytso@mit.edu>
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Description:
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The minimum number of extents the multiblock allocator
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will search to find the best extent
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What: /sys/fs/ext4/<disk>/mb_order2_req
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Date: March 2008
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Contact: "Theodore Ts'o" <tytso@mit.edu>
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Description:
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Tuning parameter which controls the minimum size for
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requests (as a power of 2) where the buddy cache is
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used
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What: /sys/fs/ext4/<disk>/mb_stream_req
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Date: March 2008
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Contact: "Theodore Ts'o" <tytso@mit.edu>
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Description:
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Files which have fewer blocks than this tunable
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parameter will have their blocks allocated out of a
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block group specific preallocation pool, so that small
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files are packed closely together. Each large file
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will have its blocks allocated out of its own unique
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preallocation pool.
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What: /sys/fs/ext4/<disk>/inode_readahead_blks
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Date: March 2008
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Contact: "Theodore Ts'o" <tytso@mit.edu>
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Description:
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Tuning parameter which controls the maximum number of
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inode table blocks that ext4's inode table readahead
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algorithm will pre-read into the buffer cache
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What: /sys/fs/ext4/<disk>/delayed_allocation_blocks
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Date: March 2008
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Contact: "Theodore Ts'o" <tytso@mit.edu>
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Description:
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This file is read-only and shows the number of blocks
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that are dirty in the page cache, but which do not
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have their location in the filesystem allocated yet.
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What: /sys/fs/ext4/<disk>/lifetime_write_kbytes
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Date: March 2008
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Contact: "Theodore Ts'o" <tytso@mit.edu>
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Description:
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This file is read-only and shows the number of kilobytes
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of data that have been written to this filesystem since it was
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created.
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What: /sys/fs/ext4/<disk>/session_write_kbytes
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Date: March 2008
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Contact: "Theodore Ts'o" <tytso@mit.edu>
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Description:
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This file is read-only and shows the number of
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kilobytes of data that have been written to this
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filesystem since it was mounted.
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What: /sys/fs/ext4/<disk>/inode_goal
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Date: June 2008
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Contact: "Theodore Ts'o" <tytso@mit.edu>
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Description:
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Tuning parameter which (if non-zero) controls the goal
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inode used by the inode allocator in preference to
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all other allocation heuristics. This is intended for
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debugging use only, and should be 0 on production
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systems.
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What: /sys/fs/ext4/<disk>/max_writeback_mb_bump
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Date: September 2009
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Contact: "Theodore Ts'o" <tytso@mit.edu>
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Description:
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The maximum number of megabytes the writeback code will
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try to write out before move on to another inode.
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