<http://www.solarisinternals.com/wiki/index.php/ZFS_Best_Practices_Guide#RAID-Z_Configuration_Requirements_and_Recommendations> says that the number of disks in a RAIDZ should be (N+P) with N = {2,4,8} and P = {1,2}.
But if you go down the page just a little further to the thumper configuration examples, none of the 3 examples follow this recommendation! I will have 10 disks to put into a RAIDZ. I would like as little "waste" as possible, so that means just 1 hot spare, and a 3,3,3 config for the remaining 9 is not appealing. Should I do a single 9 disk RAIDZ, per the guideline, or should I do 4,5. This is for engineering data. My workload isn't established yet but from talking to the guys the "working set" would fit in a TB and just be local to engineer workstations, while the file server will just store infrequently used data. As such, I'm inclined to do a single 9 disk RAIDZ and maximize the available disk space, which at the same time follows the configuration guideline. I'm pretty sure I already know the correct answer as I remember when this guideline was created and why. Besides just thinking out loud, I do want to emphasize the inconsistency on the wiki and suggest that it be updated or a comment added. -frank _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss