f2fs: compress: support compress level

Expand 'compress_algorithm' mount option to accept parameter as format of
<algorithm>:<level>, by this way, it gives a way to allow user to do more
specified config on lz4 and zstd compression level, then f2fs compression
can provide higher compress ratio.

In order to set compress level for lz4 algorithm, it needs to set
CONFIG_LZ4HC_COMPRESS and CONFIG_F2FS_FS_LZ4HC config to enable lz4hc
compress algorithm.

CR and performance number on lz4/lz4hc algorithm:

dd if=enwik9 of=compressed_file conv=fsync

Original blocks:	244382

			lz4			lz4hc-9
compressed blocks	170647			163270
compress ratio		69.8%			66.8%
speed			16.4207 s, 60.9 MB/s	26.7299 s, 37.4 MB/s

compress ratio = after / before

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This commit is contained in:
Chao Yu
2021-01-22 17:46:43 +08:00
committed by Jaegeuk Kim
parent 8723b85860
commit d0d83de42f
6 changed files with 152 additions and 5 deletions

View File

@@ -274,6 +274,9 @@ struct f2fs_inode {
__u8 i_compress_algorithm; /* compress algorithm */
__u8 i_log_cluster_size; /* log of cluster size */
__le16 i_compress_flag; /* compress flag */
/* 0 bit: chksum flag
* [10,15] bits: compress level
*/
__le32 i_extra_end[0]; /* for attribute size calculation */
} __packed;
__le32 i_addr[DEF_ADDRS_PER_INODE]; /* Pointers to data blocks */