ZFS RAIDZ-? Choice for VDEV Pool

[kandrey89]

Interested in what you'd pick for a RAIDZ setup for 8/9/10 disk vdev pool, do you pick RAIDZ1/RAIDZ2/RAIDZ3?

Number of disks depends on total number of disks for enclosure of course.

For 24 disks, it'd probably be 8 disks, rather than 12 disks due to the rebuild time. For 30 it'd be 10 disks, for 36 it'd be 9 disks, for 45 it'd be 9 disks.

 

[HammerSandwich]

Z1 is pretty adventurous with 8TB drives.

See this page, especially figure 4, then go with 7+2 or 8+3. Of course, if you care about only safety, not usable space, go with Z3 period.

 

[olavgg]

For 8 TB drives, using raid is just insane. Its a high risk sport. Rebuilding a damaged array will take days. You're better off using a different technology that uses erasure coding like Ceph.

 

[brutalizer]

I am using raidz3, with 11 disks. Because that is optimal. Because data disks should be 4 or 8 or 16. And then you add another 3 disks for Raidz3, so vdev size becomes 4+3=7 or 8+3=11 or 16+3=19. But try to keep it around 10 disks, so 19 disks is not optimal. 11 disks with raidz3, it is.

 

[FnordMan]

You've got it set to only allow three choices and there's more choices that i'd pick so i'll chime in here:

10 Disks: Z3 only
9 Disks: Z3 only again
8 Disks: Z2 or Z3 again.

 

[HammerSandwich]

Because data disks should be 4 or 8 or 16.

Not always. See the link in post #2.