Mirrored drives should be fine. My understanding is that write performance suffers slightly in a mirrored configuration, but random reads are much faster. In your scenario I would expect mirroring to give far superior performance than raid-z2.
We're looking to do something similar, but we're strongly considering dual parity mirrors for when we buy some Thumpers. You're getting tons of storage for your money with these servers, but the rebuild time and risk of data loss is considerable when you're dealing with busy 500GB drives. We want to ensure that we never have to try to restore a 24TB Thumper from tape backup, and that our data is protected even if a disk fails. I found this post quite an interesting read: http://blogs.sun.com/relling/entry/raid_recommendations_space_vs_mttdl It may be an obvious point, but are you aware that snapshots need to be stopped any time a disk fails? It's something to consider if you're planning frequent snapshots. Regarding the OS, I wouldn't even attempt to use those disks for data. When we buy x4500's I'll be buying a couple of spare 500GB disks so I can mirror the boot volume onto them and stick them on the shelf, just in case. A 500GB disk costs £60 or so, is it really worth risking your server over it? And finally, I've no idea what performance would be like with that many snapshots, but Sun do a 60 day free trial of that server, so if you haven't done so already, take advantage of that and test it for yourself. This message posted from opensolaris.org _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
