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| author | Andrey Sidorov <qrxd43@motorola.com> | 2012-09-19 14:14:53 -0400 |
|---|---|---|
| committer | Theodore Ts'o <tytso@mit.edu> | 2012-09-19 14:14:53 -0400 |
| commit | 18888cf0883c286f238d44ee565530fe82752f06 (patch) | |
| tree | ebdc31cf2f7589b07bea8398cfb2d812f1a179c3 | |
| parent | 59e31c156a24d483bbd2ea07d4dc96043a55b6bc (diff) | |
| download | op-kernel-dev-18888cf0883c286f238d44ee565530fe82752f06.zip op-kernel-dev-18888cf0883c286f238d44ee565530fe82752f06.tar.gz | |
ext4: speed up truncate/unlink by not using bforget() unless needed
Do not iterate over data blocks scanning for bh's to forget as they're
never exist. This improves time taken by unlink / truncate syscall.
Tested by continuously truncating file that is being written by dd.
Another test is rm -rf of linux tree while tar unpacks it. With
ordered data mode condition unlikely(!tbh) was always met in
ext4_free_blocks. With journal data mode tbh was found only few times,
so optimisation is also possible.
Unlinking fallocated 60G file after doing sync && echo 3 >
/proc/sys/vm/drop_caches && time rm --help
X86 before (linux 3.6-rc4):
# time rm -f test1
real 0m2.710s
user 0m0.000s
sys 0m1.530s
X86 after:
# time rm -f test1
real 0m0.644s
user 0m0.003s
sys 0m0.060s
MIPS before (linux 2.6.37):
# time rm -f test1
real 0m 4.93s
user 0m 0.00s
sys 0m 4.61s
MIPS after:
# time rm -f test1
real 0m 0.16s
user 0m 0.00s
sys 0m 0.06s
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrey Sidorov <qrxd43@motorola.com>
| -rw-r--r-- | fs/ext4/extents.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index cc6d2b9..a510917 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -2318,10 +2318,13 @@ static int ext4_remove_blocks(handle_t *handle, struct inode *inode, struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); unsigned short ee_len = ext4_ext_get_actual_len(ex); ext4_fsblk_t pblk; - int flags = EXT4_FREE_BLOCKS_FORGET; + int flags = 0; if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) - flags |= EXT4_FREE_BLOCKS_METADATA; + flags |= EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET; + else if (ext4_should_journal_data(inode)) + flags |= EXT4_FREE_BLOCKS_FORGET; + /* * For bigalloc file systems, we never free a partial cluster * at the beginning of the extent. Instead, we make a note |
