On 2012/9/2 13:25, David Sterba wrote: > On Fri, Aug 31, 2012 at 04:40:36PM +0200, Ben Wreder wrote: >> The disk format description implies that btrfs should be able to >> support tail packing. I just did some experimentation, and while small >> files are packed, it seems that files occupying more than one block >> are not. For example, a lot of 32769-byte files will end up taking >> over 36KB on average (a small excess due to the metadata itself). >> >> So just to confirm - btrfs does not currently support tail-packing, is that correct? > > Currently it's not the reiserfs-style tail packing. The feature is > advertised as "Space-efficient packing of small files", as Josef > replied, if a file fits into a leaf block, it's stored into the metadata > blocks. The limit is 3916 bytes for 4k blocks, without compression. If > compression is on, the 'small file' size limit is even higher for > moderately compressible files. If the actual size of the file is > 3916 bytes, no matter how compressible it is, it won't be inlined. > An example where this could apply is a > maildir, and IIRC this was why reiserfs was chosen on mail servers. > -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
