Hive does not always do a good job cleaning up after itself and will, many time leave lots of stuff in /tmp on HDFS.
Today I saw that I had 63T of data in /tmp/hive-* #humblebrag.
This script cleans up data older than N seconds, similar to find /tmp -mmin +360 -exec rm {} \;
Dump it in cron and you're good to go.