Comment by throw0101a

> why would you want to embed raid5/6 in the filesystem layer?

One of the creators of ZFS, Jess Bonwick, explained it in 2007:

> While designing ZFS we observed that the standard layering of the storage stack induces a surprising amount of unnecessary complexity and duplicated logic. We found that by refactoring the problem a bit -- that is, changing where the boundaries are between layers -- we could make the whole thing much simpler.

* https://blogs.oracle.com/bonwick/rampant-layering-violation