A short ramdisk & ZFS anecdote
By relling on Nov 16, 2005
In a status meeting one day, Jim Mauro was lamenting that his storage system kept breaking when he was trying to do ZFS performance testing. Later I dropped him a note suggesting using a ramdisk instead. Clearly, ramdisks are not persistent storage, so they aren't really usable for those things you wish to keep. But for exploring features of file systems, they can be quite handy.
# ramdiskadm -a whee 100m
# zpool create demo /dev/ramdisk/whee
# zfs create demo/forgetme
# zfs set mountpoint=/forgetme demo/forgetme
Now we can explore ZFS without actually using disk space. This might come in handy, if you don't care about the volatility of the data.