Many remain skeptical of deduplication, which hogs expensive RAM in the best-case scenario. - What’s Wrong With ZFS Today

And I do mean expensive: Pretty much every ZFS FAQ flatly declares that ECC RAM is a must-have and 8 GB is the bare minimum. In my own experience with FreeNAS, 32 GB is a nice amount for an active small ZFS server, and this costs $200-$300 even at today’s prices

And ZFS never really adapted to today’s world of widely-available flash storage: Although flash can be used to support the ZIL and L2ARC caches, these are of dubious value in a system with sufficient RAM, and ZFS has no true hybrid storage capability. It’s laughable that the ZFS documentation obsesses over a few GB of SLC flash when multi-TB 3D NAND drives are on the market. And no one is talking about NVMe even though it’s everywhere in performance PC’s.

# Where Are the Options?

Btrfs really got storage nerds excited, appearing to be a ZFS-like combination of volume manager and filesystem with added flexibility, picking up where ReiserFS flopped. And Btrfs might just become “the ZFS of Linux” but development has faltered lately, with a scary data loss bug derailing RAID 5 and 6 last year and not much heard since. Still, I suspect that I’ll be recommending Btrfs for Linux users five years from now, especially with strong potential in containerized systems.

Microsoft is busy rolling out their own next-generation filesystem. ReFS uses B+ trees (similar to Btrfs), scales like crazy, and has built-in resilience and data protection features4. When combined with Storage Spaces, Microsoft has a viable next-generation storage layer for Windows Server that can even use SSD and 3D-XPoint as a tier or cache.

Apple, which reportedly rebooted their next-generation storage layer a few times before coming up with APFS, launched this year in macOS High Sierra. APFS looks a lot like Btrfs and ReFS,

Still, ZFS is way better than legacy storage SOHO filesystems. The lack of integrity checking, redundancy, and error recovery makes NTFS (Windows), HFS+ (macOS), and ext3/4 (Linux) wholly inappropriate for use as a long-term storage platform. And even ReFS and APFS, lacking data integrity checking, aren’t appropriate where data loss cannot be tolerated.