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author | Dave Chinner <dchinner@redhat.com> | 2024-08-13 10:39:38 +0300 |
---|---|---|
committer | Chandan Babu R <chandanbabu@kernel.org> | 2024-09-03 07:37:38 +0300 |
commit | 816e3599ca9b9bbfdc456433cc707e75f2c31104 (patch) | |
tree | 069f225f91b2a25c90f35b8434478419f5cbffd5 /fs/xfs/xfs_file.c | |
parent | c741d79c1a975cc3904ed8a491d6338ac852d43d (diff) | |
download | linux-816e3599ca9b9bbfdc456433cc707e75f2c31104.tar.xz |
xfs: don't free post-EOF blocks on read close
When we have a workload that does open/read/close in parallel with other
allocation, the file becomes rapidly fragmented. This is due to close()
calling xfs_file_release() and removing the speculative preallocation
beyond EOF.
Add a check for a writable context to xfs_file_release to skip the
post-EOF block freeing (an the similarly pointless flushing on truncate
down).
Before:
Test 1: sync write fragmentation counts
/mnt/scratch/file.0: 919
/mnt/scratch/file.1: 916
/mnt/scratch/file.2: 919
/mnt/scratch/file.3: 920
/mnt/scratch/file.4: 920
/mnt/scratch/file.5: 921
/mnt/scratch/file.6: 916
/mnt/scratch/file.7: 918
After:
Test 1: sync write fragmentation counts
/mnt/scratch/file.0: 24
/mnt/scratch/file.1: 24
/mnt/scratch/file.2: 11
/mnt/scratch/file.3: 24
/mnt/scratch/file.4: 3
/mnt/scratch/file.5: 24
/mnt/scratch/file.6: 24
/mnt/scratch/file.7: 23
Signed-off-by: Dave Chinner <dchinner@redhat.com>
[darrick: wordsmithing, fix commit message]
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
[hch: ported to the new ->release code structure]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Diffstat (limited to 'fs/xfs/xfs_file.c')
-rw-r--r-- | fs/xfs/xfs_file.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index dae8dd122355..60424e642307 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -1217,12 +1217,18 @@ xfs_file_release( * There is no point in freeing blocks here for open but unlinked files * as they will be taken care of by the inactivation path soon. * + * When releasing a read-only context, don't flush data or trim post-EOF + * blocks. This avoids open/read/close workloads from removing EOF + * blocks that other writers depend upon to reduce fragmentation. + * * If we can't get the iolock just skip truncating the blocks past EOF * because we could deadlock with the mmap_lock otherwise. We'll get * another chance to drop them once the last reference to the inode is * dropped, so we'll never leak blocks permanently. */ - if (inode->i_nlink && xfs_ilock_nowait(ip, XFS_IOLOCK_EXCL)) { + if (inode->i_nlink && + (file->f_mode & FMODE_WRITE) && + xfs_ilock_nowait(ip, XFS_IOLOCK_EXCL)) { if (xfs_can_free_eofblocks(ip) && !xfs_iflags_test(ip, XFS_IDIRTY_RELEASE)) { /* |