Pool configurations question

System I5-9500. 64 GB DDR4 memory. 10 GB PCIE card.

3 x 22 TB drives HDD
4 x 8 TB drives HDD

Looking for straight speed. No resiliency necessary. Mainly torrent and plex storage

1 pool - 2 Vdevs (3x22) (4x8)
1 pool mirrored all 7 drives (2 vdevs? 3 vdevs?)
1 pool striped all 7 drives

Suggestions? Thank you

For greatest speed and no redundancy,


The key thing to remember about a non-redundant pool is that you lose the entire pool if ANY of the disks fail - so the more disks in the pool, the more likely it is to fail completely. A single striped pool of 98TB across 7 disks is a LOT of data to lose with 7x the likelihood of failure cf. a single drive.

My advice would be to have redundancy, and to create a single pool consisting of 2 RAIDZ1 vDevs - A) 3x22TB which gives you 44TB of space and B) 4x8TB which gives you another 24TB of space.

In reality, in total you would probably get about 40TiB-45TiB of useable space from this (bearing in mind all the overheads - such as TB to TiB conversion, metadata, and a realistic maximum utilisation of 80% etc.).

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And the speed of a failed pool is zero.

This is my advise too. And in Electric Eel RaidZ expansion is a thing.

As mentioned before, a failed pool is not very fast.

Redundancy is an availability technique.

OTOH, with a striped pool, if a drive starts looking dodgy, you can remove it. Any data on bad sectors will still be affected, of course, but it may be possible to remove a failing drive before it fails completely.

I’m not one to recommend striped pools, but that’s what best meets OP’s stated objectives.