Thanks for the reply vishwanath, honestly I am a bit confused here too. Have tried out the recommended settings also given in the forums -
query_cache_type = 1
query_cache_size = 36M
query_cache_min_res_unit = 2K
cache with table_cache = 512
also , since its a vps , its a managed server, i don't have the full access but i can ask them to install anything and they will do it.
the main problem started with the database lockup, from the log given to us by the hosting support team we came to know the session table was choking up hence we moved to a file based session.After moving to a file based session, the problem of lockup sorted out but, the 500 error became frequent.
can you help me out with some pointers on where to begin with the debug, if there is something i can check out in the course logs let me know.