When you load test your sites, be sure to use realistic tests.
Don’t rely on throughput data from a test script in which 100 separate clients make an identical request at the same moment.
You will want to test cases where request threads do and do not accept cookies. However, be aware that if you run a performance test in which every request does not accept cookies, your results will reflect a high performance cost from the need to create a session object for each request. You can easily exhaust memory by creating too many sessions.