Defrag heuristic use extent lengh as threshold,
kernel autodefrag use SZ_256KiB and btrfs-progs use SZ_32MiB as
target extent lengh.
Problem:
Compressed extents always have lengh at < 128KiB (BTRFS_MAX_COMPRESSED)
So btrfs_defrag_file() always rewrite all extents in defrag range.
Hot fix that by force set target extent size to BTRFS_MAX_COMPRESSED,
if file allowed to be compressed.
Signed-off-by: Timofey Titovets <nefelim...@gmail.com>
---
fs/btrfs/ioctl.c | 23 +++++++++++++++++++++++
1 file changed, 23 insertions(+)
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index be5bd81b3669..952364ff4108 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -1232,6 +1232,26 @@ static int cluster_pages_for_defrag(struct inode *inode,
}
+static inline int inode_use_compression(struct inode *inode)
+{
+ struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
+
+ /* force compress */
+ if (btrfs_test_opt(fs_info, FORCE_COMPRESS))
+ return 1;
+ /* defrag ioctl */
+ if (BTRFS_I(inode)->defrag_compress)
+ return 1;
+ /* bad compression ratios */
+ if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS)
+ return 0;
+ if (btrfs_test_opt(fs_info, COMPRESS) ||
+ BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS ||
+ BTRFS_I(inode)->prop_compress)
+ return 1;
+ return 0;
+}
+
int btrfs_defrag_file(struct inode *inode, struct file *file,
struct btrfs_ioctl_defrag_range_args *range,
u64 newer_than, unsigned long max_to_defrag)
@@ -1270,6 +1290,9 @@ int btrfs_defrag_file(struct inode *inode, struct file
*file,
compress_type = range->compress_type;
}
+ if (inode_use_compression(inode))
+ extent_thresh = BTRFS_MAX_COMPRESSED;
+
if (extent_thresh == 0)
extent_thresh = SZ_256K;
--
2.15.1
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