swap on ZFS

zfs create -V 8G -b $(getconf PAGESIZE) -o compression=zle \
      -o logbias=throughput -o sync=always \
      -o primarycache=metadata -o secondarycache=none \
      -o com.sun:auto-snapshot=false rpool/swap
 
mkswap -f /dev/zvol/rpool/swap 
UUID=04abad40-3f64-4e42-b9fd-9126f30d2dab	none	swap	defaults	0	0