[projct]

On ZFS you can have multiple vdevs of different sizes in the same pool, and you can also set copies=N to have multiple copies of the data available for extra redundancy.

You can't unfortunately tell it that different disks have different speeds.

It also works just fine w/ a small (1GB or so) ARC if you want, just at an obvious performance penalty compared to having a larger cache.

[zaarn]

ZFS cannot have different sizes in a single vdev and I'm tired of having to explain this to people everytime I mention this issue.