Places where locks are held unnecessarily in BIND9.3.1

[narendar reddy]

Sir,
I want to analyze all the mutex lock contentions in
the query processing path and look at places where threads are blocking
unnecessarily and waitnig for a lock in BIND9.3.1threaded architecture. For
this i am using HP Caliper tool
and I installed BIND9.3.1 on IA-64 (Iitanium) processor.
How to understand the code in the query path (the files that are used when
answering a query by the name server)  to identify the lock overheads.
I am trying to understand code from past 2 to 3 months, but i am unable to
do this. tell me
if there are any open source tools available to do this.
Please tell me the files that are used in query processing path and how to
study the code and how to identify where
locks are held.
Thanking You