The load on an Online Exam System is very different from the data contained by the system. It is not the number of registered students. It is also not the number of questionnaires uploaded.
Till the time there is no use of system to solve the test by a candidate, there is no load. It is just a dead database which is occupying disk space. But since there is no transaction and use of data bandwidth, thus we call this situation as a no-load condition.
There can be 100 or 10000 registered candidates and there might be 1 or 250 question papers ready uploaded in your system BUT still there will be no load if no candidate is solving any question paper at this point of time. The actual usage of the system begins when a user starts attempting a question paper.
When a candidate solves a question paper the database of the Online Exam system is repeatedly hit several times in a minute to retrieve and store the latest responses or changes made by the candidate. It is only then that the bandwidth and other capabilities of the database server are put to use.
It is also to understand that the load exerted during a single Online Exam activity per user is much higher than the total load exerted by that user for other dashboard activities during the entire year.