ZFS might not have the single disk, raw synthetic benchmark performance of a stupid file system with no correctness/integrity built in, but that use case isn't

ZFS might not have the single disk, raw synthetic benchmark performance of a stupid file system with no correctness/integrity built in, but that use case isn't really what anyone wants or needs. ZFS isn't really a filesystem. It's more like a storage backend, that happens to support the POSIX interface. The original intent of ZFS was to completely rethink the volume management/filesystem layering nonsense, and to provide for storage what the MMU/VM system provides for memory. So it can do much more interesting things like memory backed read caching (via ARC), SSD backed read caching (via L2ARC), and SSD backed write buffering (via ZIL/SLOG), as well as the normal RAID stuff.