I'm aware of how both work (I had a VCP410 cert and happily run ZFS with many snapshots on rotation at home), but IMO the uses are similar enough for the purpos

I'm aware of how both work (I had a VCP410 cert and happily run ZFS with many snapshots on rotation at home), but IMO the uses are similar enough for the purposes explored in the article despite the significant differences in practice and felt that a traditional alternative should be mentioned. Additionally, VMware-based snapshots can be performed SAN-side and integrated with VAAI that can expect similar performance overhead as a ZFS snapshot and still support a lot of options with trade-offs and features. The compulsory indirections that happen in the traditional VMware snapshot implementation with the on-disk block map appears designed for storage compatibility (much like the design of VMFS in itself, including with that whole file-based mutex system) primarily rather than performance not to mention the support for memory persistence / quiescing with the guest OS, which ZFS snapshots do not support. In contrast, ZFS has all the metadata to quickly examine block time or other rich metadata to accelerate read and write indirection of blocks optimally. It's not clear if a SAN can accelerate ZFS using OSes in the way that they can accelerate VMware storage but I'm curious of the potential. On the other hand, recursive snapshots in ZFS are really slick and can achieve 90%+ of what people typically want from VMware-based snapshots when it comes to any non-Windows OS if there's a little room for not needing to care about indirect changes required in rollbacks.