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.