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But then, how does it count something as a 'current session'. I reset-stats-- that value does not zero but stays about the same value as before the reset, but it never seems to goes down. Trying to understand the concept of a 'session' on a transaction-based pool (web traffic). In my case the virtual servers using the pool have session cookie persistence, so the Big-IP won't know how many cookies are out there in browsers that are still in an active session. I'd ignore this number, but I know it is going to be a question as some of the server and application people are looking to see when the traffic had 'drained' and wonder why 'current sessions' doesn't go to zero. Thanks..