Passivation allows the state of a Java object — such as an entire PRPC PRThread context, including the clipboard state — to be saved to a file. A later operation, known as activation, restores the object. PRPC uses standard passivation in general operation, but you can also configure passivation to shared storage in highly available environments.
PRPC can support HTTP session passivation and requestor clipboard page passivation. Configuration is controlled by entries in the prconfig.xml
file, or by Dynamic System Settings.
When all or part of a requestor clipboard is idle for an extended period and available JVM memory is limited, PRPC automatically saves clipboard pages in a disk file on the server. This frees up JVM memory for use by active requestors. (Typically, such passivation occurs only on systems supporting 50 or more simultaneous requestors.)
Optional HTTP session passivation can help provide high availability in a multinode environment. If a node fails, activation of the session can usually continue on a different node. This allows a cluster to operate in a resilient manner, reducing the risk of loss of data if a node fails.
In a single-node system, the OnTimeOut
passivation setting allows a user to resume work without loss of context after leaving the browser window idle for a period. The user may be required to reauthenticate.
Passivation in PRPC is similar in purpose and results to Java EE EJB bean passivation, but PRPC passivation does not require Enterprise Archive (EAR file) deployments or use a Java EE passivation interface. PRPC passivation can occur on any platform, including Tomcat.
High Availability features enable the use of shared storage for passivation. See the High Availability Administration Guide for details.