Hello,
What version of SEP 11.x are you running?
What is the OS are you running SEPM on?
There could be many reason, that the Symantec Embedded database process hungs up.
Major reason could be Lack of Resources, permissions, etc.
Check this Article which may help you:
Monitoring Server Health on Symantec Endpoint Protection Manager
http://www.symantec.com/docs/TECH122731
Again, have you given a thought of Migrating to SEP 12.1?
Hope that helps!!