Currently the are a few options that determine when automatic compaction is triggered. They are specified once for the warehouse.
This doesn't make sense - some table may be more important and need to be compacted more often.
We should allow specifying these on per table basis.
Also, compaction is an MR job launched from within the metastore. There is currently no way to control job parameters (like memory, for example) except to specify it in hive-site.xml for metastore which means they are site wide.
Should add a way to specify these per table (perhaps even per compaction if launched via ALTER TABLE)