Are you a diligent DBA who applies quarterly CPU patches whenever possible? Are you noticing how the $ORACLE_HOME directory gets larger and larger over time? That’s ’cause the opatch utility creates backup files needed for rolling back patches in a directory called $ORACLE_HOME/.patch_storage. Opatch will not eliminate old files here when you apply patches. However, starting in Oracle 10.2.0.x and higher, there is now a switch for opatch: opatch util cleanup. This will remove backup files from older patches that are no longer needed. Search on metalink for more details. This cleared up 2GB for me yesterday!