Frozen Threads

Question

Hi,

Please let me know if this is not the best forum for this question.

I have a C# program that starts 20 threads.  Each thread is a TCP listener receiving events from Network Elements, writing the events to a DB, and also writing a log file recording errors, state changes, etc.   

Every couple days or so, all 20 threads appear to freeze at the exact same time.  This statement is based on the last time stamp in each of the 20 threads' log file.  

Does anyone what might cause this ??  The thread's main loop is wrapped in a try/catch block that logs the caught exception to disk but the log file contains no exceptions and there is over 60GB of free disk space on the drive I'm writing the logs.

Does anyone have any ideas on what might be going on and how to resolve it ??   What would cause all 20 threads to "freeze" at the same time and never recover/start again apparently not throwing any exceptions ??

TIA,
Matt