Is it possible, within an 8.3.0-RC1 Jail, to have /tmp (and /var/tmp) mounted in memory (ie. tmpfs)? MySQL will, by default, create temporary files in /var/tmp- even when performing read-only queries (ie. SELECT). This is causing excessive disk writes to ZFS (which is where /var/tmp lives inside a Jail), and prevents the disks from spinning down (assuming ataidle worked, which isn't actually the case in 8.3.0-RC1, but I digress). Unfortunately, the Jail seems to have no access to volatile storage such as tmpfs, so activity that wouldn't normally trigger disk activity outside of a jail, do so inside of a jail. The only obvious solution appears to be to lump the entire Jail on to a USB memory stick, but if possible I'd rather shift /var/tmp and /tmp into RAM. Anyone got any ideas?