I am monitoring a Websphere Application Server and especially Http Sessions using PMI interface.
The two major metrics here are:
Live Sessions described as:
The number of local sessions that are currently cached in memory from the time at which this metric is enabled.
Active Sessions described as:
The number of concurrently active sessions. A session is active if the WebSphere® Application Server is currently processing a request that uses that session.
My question is what is the actual relation between the two metrics?
Could the sessions included in one metric be also included to the other?
My opinion based on the results I get till now is that there is no intersection between the two sets of live and active sessions.
All active sessions are included in the live sessions counter.
Live sessions contain all valid sessions in the JVM while active sessions contain sessions being accessed / used at the time you interrogate this PMI counter.
Hope this helps !
Richard Levac
WasMonitor - WebSphere Data Collector and More !