Each HTTP session has a validity set to it. HTTP sessions that have exceeded validity, found as a result of checking validity on the basis of the information of the last access time, are deleted. When an HTTP session has deleted because it exceeded validity, corresponding global session information is also deleted as an extension of that processing.

Validity monitoring threads existing in web container periodically monitor the validity of HTTP sessions. Validity monitoring threads exist for every Web application.

The following figure shows the flow of processing executed when deleting global session information due to expiry of validity.

Figure 6-6 Processing when validity of global session information expires (the database session failover functionality)

1. If integrity mode is enabled, the global session information corresponding to the session, the validity of which is determined to have expired by using validity monitoring threads, is locked.
2. The HTTP session is deleted as an extension of session deletion processing. The global session information and the blank record information in the database are deleted when the HTTP session is deleted.
   If integrity mode is enabled, the lock is released.