Usually there is some "reserved" space for superuser (sic), and then there is the fs overhead (i-node tables, etc). Depends on the filesystem.
ext2/3/4 has a default reserve of 5% for uid0 (-m
) depending on the usage-type (-T
) i-node space is pre-allocated - see df -ih
I'd say the 14G are really available, but there may be 40G of reserve and say 100MB of i-nodes, which would pretty much add up. #ymmw