Apparently, in the ZFS (filesystem), there is an uberblock that points to the root of a zpool tree. Does anyone know why this tree makes things more efficient/reliable, and where the tree itself is stored?
The purpose of the tree is to improve data integrity, partly by storing checksums away from the data blocks those checksums protect. The entire file system hierarchy forms a self-healing hash tree, or merkle tree. Here's a simplified description I made earlier:
ZFS also uses ditto blocks to replicate the more important parts of the tree (i.e., the parts closer to the root), to further protect against corruption.