Michael Herf wrote: > I've written about my slow-to-dedupe RAIDZ. > > After a week of.....waiting....I finally bought a > little $100 30G OCZ > Vertex and plugged it in as a cache. > > After <2 hours of warmup, my zfs send/receive rate on > the pool is > >16MB/sec (reading and writing each at 16MB as > measured by zpool > iostat). > That's up from <3MB/sec, with a RAM-only cache on a > 6GB machine. > > The SSD has about 8GB utilized right now, and the > L2ARC benefit is amazing. > Quite an amazing improvement for $100...recommend you > don't dedupe without one.
I did something similar, but with a SCSI drive. I keep a large external USB drive as a "last ditch" recovery pool which is synchronized hourly from the main pool. Kind of like a poor man's tape backup. When I enabled dedup=verify on the USB pool, the sync performance went south, because the USB drive had to read stripes to verify that they were actual dups. Since I had an unused 146GB SCSI drive plugged in, I made the SCSI drive L2ARC for the USB pool. Write performance skyrocketed by a factor of 6 and is now faster than when there was no dedupe enabled. Marty -- This message posted from opensolaris.org _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
