@mischievoustomato And like so far the only thing that makes sense that's truly against ZFS but I haven't measured is ZFS being somewhat slower for database writes, which in a way makes sense since you're doing ACID (CoW-ish) on CoW.

But I wonder for what workloads it becomes a problem, at least for Pleroma (which means pretty regular writes) it seems to be fine, even on devboards where the I/Os are horrible.