Dedup doesn't really induce extra CPU usage - you need to calculate checksums anyway. However it does require sha256 checksums instead of fletcher but still, usually it's not CPU which is a problem.
But then being able to dedup your data later could make your writes much faster depending on configuration and workload. This should be possible once the famous bp_rewriter hits public. -- Robert Milkowski http://milek.blogspot.com > -----Original Message----- > From: [email protected] [mailto:zfs-code- > [email protected]] On Behalf Of Siegfried Leonard > Sent: 02 April 2011 10:08 > To: [email protected] > Subject: [zfs-code] Manual deduplication scrubs > > Hello all, > > Is it possible to do deduplication in place when the system is idle? That > would be pretty useful to keep performance on low memory systems or not > increase CPU usage of slower machines such that the filesystem > performance would be decreased if using the live approach. > > Is this even feasible? Would the dedup database be updated from the last > run? Kind of like a ZFS snapshot being taken, except in this case I don't think > it can be implemented using ZFS snapshots, or can it? Would the > performance benefit of this be worth enough implementing? > > Just some thoughts, ideas, and questions. Let me know your opinion. > > > Cheers, > Siegfried > -- > This message posted from opensolaris.org > _______________________________________________ > zfs-code mailing list > [email protected] > http://mail.opensolaris.org/mailman/listinfo/zfs-code _______________________________________________ zfs-code mailing list [email protected] http://mail.opensolaris.org/mailman/listinfo/zfs-code
