Servlet session counters

Use this page as a reference for properties of servlet session counters.

Data counters for this category contain usage information for HTTP sessions.

Counter definitions

Name	Key	Description	Granularity	Type	Level	Overhead
CreateCount	servletSessionsModule.createdSessions	The number of sessions that were created	Per Web application	CountStatistic	All	Low
InvalidateCount	servletSessionsModule.invalidatedSessions	The number of sessions that were invalidated	Per Web application	CountStatistic	All	Low
LifeTime	servletSessionsModule.sessionLifeTime	The average session life time in milliseconds (time invalidated - time created)	Per Web application	TimeStatistic	Extended	Medium
ActiveCount	servletSessionsModule.activeSessions	The number of concurrently active sessions. A session is active if the WAS is currently processing a request that uses that session.	Per Web application	RangeStatistic	All	High
LiveCount	servletSessionsModule.liveSessions	The number of local sessions that are currently cached in memory.	Per Web application	RangeStatistic	Basic	High
NoRoomForNewSessionCount	servletSessionsModule.noRoomForNewSession	Applies only to session in memory with AllowOverflow=false. The number of times that a request for a new session cannot be handled because it exceeds the maximum session count.	Per Web application	CountStatistic	Extended	Low
CacheDiscardCount	servletSessionsModule.cacheDiscards	The number of session objects forced out of the cache. A least recently used (LRU) algorithm removes old entries to make room for new sessions and cache misses. Applicable only for persistent sessions.	Per Web application	CountStatistic	All	Low
ExternalReadTime	servletSessionsModule.externalReadTime	The time (milliseconds) taken in reading the session data from the persistent store. For multirow sessions, the metrics are for the attribute; for single row sessions, the metrics are for the entire session. Applicable only for persistent sessions. When using a JMS persistent store, you can choose to serialize the replicated data. If you choose not to serialize the data, the counter is not available.	Per Web application	TimeStatistic	Extended	Medium
ExternalReadSize	servletSessionsModule.externalReadSize	Size of the session data read from persistent store. Applicable only for (serialized) persistent sessions; similar to external Read Time.	Per Web application	TimeStatistic	Extended	Medium
ExternalWriteTime	servletSessionsModule.externalWriteTime	The time (milliseconds) taken to write the session data from the persistent store. Applicable only for (serialized) persistent sessions. Similar to external Read Time.	Per Web application	TimeStatistic	Extended	Medium
ExternalWriteSize	servletSessionsModule.externalWriteSize	The size of the session data written to persistent store. Applicable only for (serialized) persistent sessions. Similar to external Read Time.	Per Web application	TimeStatistic	Extended	Medium
AffinityBreakCount	servletSessionsModule.affinityBreaks	The number of requests that are received for sessions that were last accessed from another Web application. This value can indicate failover processing or a corrupt plug-in configuration.	Per Web application	CountStatistic	All	Low
SessionObjectSize	servletSessionsModule.serializableSessObjSize	The size in bytes of (the serializable attributes of ) in-memory sessions. Only session objects that contain at least one serializable attribute object is counted. A session can contain some attributes that are serializable and some that are not. The size in bytes is at a session level.	Per Web application	TimeStatistic	All	Max
TimeSinceLastActivated	servletSessionsModule.timeSinceLastActivated	The time difference in milliseconds between previous and current access time stamps. Does not include session time out.	Per Web application	TimeStatistic	All	Medium
TimeoutInvalidationCount	servletSessionsModule.invalidatedViaTimeout	The number of sessions that are invalidated by timeout.	Per Web application	CountStatistic	All	Low
ActivateNonExistSessionCount	servletSessionsModule.activateNonExistSessions	The number of requests for a session that no longer exists, presumably because the session timed out. Use this counter to help determine if the timeout is too short.	Per Web application	CountStatistic	All	Low

 

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