ZFS

zpool list
zpool list <poolname>
zpool status
zpool status -x
zpool status -v <poolname>
zpool iostat
zpool iostat -v
zpool history

1GB Cache per 1 TB Storage

Set Cache Min/Max

cat << 'EOF' > /etc/modprobe.d/zfs.conf
options zfs zfs_arc_min=3221225472
options zfs zfs_arc_max=4294967296
EOF

update-initramfs -u && reboot