From a6fa6fae40ec336c7df6155255ae64ebef43a8bc Mon Sep 17 00:00:00 2001 From: Li Zefan Date: Mon, 25 Oct 2010 15:12:26 +0800 Subject: btrfs: Add lzo compression support Lzo is a much faster compression algorithm than gzib, so would allow more users to enable transparent compression, and some users can choose from compression ratio and speed for different applications Usage: # mount -t btrfs -o compress[=] dev /mnt or # mount -t btrfs -o compress-force[=] dev /mnt "-o compress" without argument is still allowed for compatability. Compatibility: If we mount a filesystem with lzo compression, it will not be able be mounted in old kernels. One reason is, otherwise btrfs will directly dump compressed data, which sits in inline extent, to user. Performance: The test copied a linux source tarball (~400M) from an ext4 partition to the btrfs partition, and then extracted it. (time in second) lzo zlib nocompress copy: 10.6 21.7 14.9 extract: 70.1 94.4 66.6 (data size in MB) lzo zlib nocompress copy: 185.87 108.69 394.49 extract: 193.80 132.36 381.21 Changelog: v1 -> v2: - Select LZO_COMPRESS and LZO_DECOMPRESS in btrfs Kconfig. - Add incompability flag. - Fix error handling in compress code. Signed-off-by: Li Zefan --- fs/btrfs/compression.h | 1 + 1 file changed, 1 insertion(+) (limited to 'fs/btrfs/compression.h') diff --git a/fs/btrfs/compression.h b/fs/btrfs/compression.h index 9b5f2f365b79..f7ce217113fa 100644 --- a/fs/btrfs/compression.h +++ b/fs/btrfs/compression.h @@ -73,5 +73,6 @@ struct btrfs_compress_op { }; extern struct btrfs_compress_op btrfs_zlib_compress; +extern struct btrfs_compress_op btrfs_lzo_compress; #endif -- cgit v1.2.1