I remember being surprised to learn a while back that all writes over NFS were treated as sync, so putting a ZIL on an Optane (for example) helped with NFS performance enormously.
This would have been on FreeBSD, I don't know if the same is still true, or true on ZoL.
This would have been on FreeBSD, I don't know if the same is still true, or true on ZoL.