[QUESTION] 16 drives, best ZFS RAIDZ2 scheme

[DearestDreamer]

Hello,

I have 16 bays which I'd like to utilize to the fullest and I read that when creating vdevs we should follow the 2^n+parity rule, so I have a questionf about the following setups:

I was initially going to go for 2 RAIDZ2 vdevs in my pool, 8(6drives+2parity)x2.
Now I'm considering one vdev with 10 drives (8+2) in RAIDZ2 and another vdev with 6 drives (4+2) in RAIDZ2, this way I'm complying with the recommended formula.

So my question is, whether I'm taking a huge performance/storage hit with my first setup or if it'll be fine? Furthermore, can I mix vdevs of different sizes like the second option I described (1x10+1x6)?

I forgot to mention that the use case in this scenario is a streaming server for media. While http://blog.delphix.com/matt/2014/06/06/zfs-stripe-width/ explains that the formula I mentioned is "generally" wrongfully recommended, I am a little bit hung up on his wording since he uses the word "generally" and not "definitely"..

 

[Fuganater]

I'm a bit OCD so I like things to be the same. 2x 8 disk RAIDZ2

 

[Robert Trevellyan]

+1

I read that when creating vdevs we should follow the 2^n+parity rule

As explained in the article you referenced, your use case does not indicate 2^n+p (EDIT: because it doesn't involve "exact fitting of blocks into stripes").

 

[DearestDreamer]

So I should be just fine with 2x8 RAIDZ2 then.. alright, thank you guys so much!