Brian Hechinger wrote:
Ok, previous threads have lead me to believe that I want to make raidz vdevs [0] either 3, 5 or 9 disks in size [1]. Let's say I have 8 disks. Do I want to create a zfs pool with a 5-disk vdev and a 3-disk vdev? Are there performance issues with mixing differently sized raidz vdevs in a pool? If there *is* a performance hit to mix like that, would it be greater or lesser than building an 8-disk vdev?
Unless you are running a database (or other record-structured application), or have specific performance data for your workload that supports your choice, I wouldn't worry about using the power-of-two-plus-parity size stripes.
I'd choose between (in order of decreasing available io/s): 4x 2-way mirrors (most io/s and most read bandwidth) 2x 4-way raidz1 1x 8-way raidz1 (most write bandwidth) 1x 8-way raidz2 (most redundant)
[0] - Just for clarity, what are the "sub-pools" in a pool, the actual raidz/mirror/etc "containers" called. What is the correct term to refer to them? I don't want any extra confusion here. ;)
We would usually just call them "vdevs" (or to be more specific, "top-level vdevs").
--matt _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
