On Thu, Feb 25, 2021 at 02:26:47PM +0100, David Sterba wrote: > > LZ4 support has been asked for so many times that it has it's own FAQ > entry: > https://btrfs.wiki.kernel.org/index.php/FAQ#Will_btrfs_support_LZ4.3F > > The decompression speed is not the only thing that should be evaluated, > the way compression works in btrfs (in 4k blocks) does not allow good > compression ratios and overall LZ4 does not do much better than LZO. So > this is not worth the additional costs of compatibility. With ZSTD we > got the high compression and recently there have been added real-time > compression levels that we'll use in btrfs eventually. When ZSTD support was being added to btrfs, it was claimed that btrfs compresses up to 128KB at a time (https://lore.kernel.org/r/5a7c09dd-3415-0c00-c0f2-a605a0656499@xxxxxx). So which is it -- 4KB or 128KB? - Eric
