Ah, I see. ashift is definitely 12 (as I noted in my sibling reply)... but TIL about alignment (thanks). Parted says my ZFS partition starts at 8590983168 byte

Ah, I see. ashift is definitely 12 (as I noted in my sibling reply)... but TIL about alignment (thanks). Parted says my ZFS partition starts at 8590983168 bytes (after an 8GB swap partition), which divides down by 4K cleanly. Is that what you mean? Hmm, the RAM usage on this machine is generally low-ish, but with 8GB I suspect the smallest perturbations can make a big difference (even though I use it headlessly). I'll definitely keep more RAM in mind going forward, and yeah, SSD/NVME storage makes these kinds of considerations moot in high-performance contexts. Thanks for the info!