There's a lot of discussion of dedup performance issues (including problems backing out of using it which concerns me), but many/most of those involve relatively limited RAM and CPU configurations. I wanted to see if there is experience that people could share using it on with higher RAM levels and l2arc.
We have built a backup storage server nearly identical to this: http://www.natecarlson.com/2010/05/07/review-supermicros-sc847a-4u-chassis-with-36-drive-bays/ briefly: SuperMicro 36 bay case 48 GB RAM 2x 5620 CPU Hitachi A7K2000 drives for storage X25-M for l2arc (160 GB) 4x LSI SAS9211-8i Solaris 11 Express The main storage pool is mirrored and uses gzip compression. Our use consists of backing up daily snapshots of multiple MySQL hosts from a Sun 7410 appliance. We rsync the snapshot to the backup server (ZFS send to non-appliance host isn't supported on the 7000 unfortunately), snapshot (so now we have a snapshot of that matches the original on the 7410), clone, start MySQL on the clone to verify the backup, shut down MySQL. We do this daily across 10 hosts which have significant overlap in data. I might guess that dedup would provide good space savings, but before I turn it on I wanted to see if people with larger configurations had found it workable. My greatest concern are stories of not only poor performance but worse complete non-responsiveness when trying to zfs destroy a filesystem with dedup turned on. We are somewhat flexible here. We are not terribly pressed for space, and we do not need massive performance out of this. Because of that I probably won't use dedup without hearing it is workable on a similar configuration, but if people have had success it would give us more cushion for inevitable data growth. Thanks for any help, Ware _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
