I am writing a new web application with a traffic of around 6k to 12k users connected for around 1.5 to 2 hrs. It is kind of an online examination. Can any one tell me

what r the perl code changes to be made for such huge scalability ?

what r the server side changes ?

what r the database side changes (as the basic system has non partitioned table, single user etc) ?

alternatives of backend languages for the requirement ?