On Tue, Aug 22, 2006 at 08:43:32AM -0700, roland wrote: > can someone tell, how effective is zfs compression and > space-efficiency (regarding small files) ? > > since compression works at the block level, i assume compression may > not come into effect as some may expect. (maybe i`m wrong here)
It's true that since we are compressing a block at a time, there are some efficiencies of whole-large-file compression that will be lost. However, since ZFS uses 128k blocks on large files, the difference should be neglegable. For smaller files, ZFS uses a single block that exactly fits the file (compressed or not) (rounded up to the nearest sector size (512 bytes)). So I believe that ZFS's compression infrastructure permits good efficiency. However, at this point, we have only implemented one compression algorithm, which is much faster than, but does not compress as much as, gzip. We plan to implement a broader range of compression algorithms in the future. --matt _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
