Running Offline compaction on AEM 6.4 is not recommended as per the official documentation at [1]. 6.4 offers tail online compaction every day and full online compaction once a week, you should leverage those features.
When to use Online Revision Cleanup as opposed to Offline Revision Cleanup?
Online Revision Cleanup is the recommended way of performing revision cleanup. Offline Revision cleanup should be used only on an exceptional basis - for example, before migrating to the new storage format or if you are requested by Adobe Customer Care to do so.
[1] Revision Cleanup
