How does the master agent interleaves requests/agentx/traps?

Hey,
 
As I understand the master agent is not multi-threaded, hense it deals
synchroniously with:
    - receiving/sending to SNMP requests
    - dispatching/retrieving requests with agentX  APUDs
    - sending traps
    - listens for sub-agent registration/diregistration
 
Questions:
---------------
1) How does it manage all of these? What's the program-flow for
interleaves these tasks?
2) Can a burst of traps, deny request handling?
  

Thanks,

Erez Makavy