On May 5, 2010, at 8:35 PM, Richard Jahnel wrote: > Hmm... > > To clarify. > > Every discussion or benchmarking that I have seen always show both off, > compression only or both on. > > Why never compression off and dedup on?
I've seen this quite often. The decision to compress is based on the compressibility of the data. The decision to dedup is based on the duplication of the data. > After some further thought... perhaps it's because compression works at the > byte level and dedup is at the block level. Perhaps I have answered my own > question. Both work at the block level. Hence, they are complementary. Two identical blocks will compress identically, and then dedup. -- richard -- ZFS storage and performance consulting at http://www.RichardElling.com _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
