NonStop Servlets for JavaServer Pages (NSJSP) 6.1 System Administrator's Guide

Configuring NSJSP
NonStop Servlets for JavaServer Pages (NSJSP) 6.1 System Administrator’s Guide—596210-006
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Mixed-Mode Sessions
Mixed-Mode Sessions
In NSJSP 6.1, you can also a configure a mixed-mode session. In a mixed-mode
session, a session can be configured so that it is kept in memory and also saved to a
persistent store at regular intervals.
When configured this way, the sessions exhibit the sticky sessions behavior (similar to
the behavior when SessionBasedLoadBalancing is enabled for in memory
sessions). This means that all requests for a particular session are routed to the same
Servlet Server Class process. The sessions are also persisted to the store at regular
intervals. The interval is calculated based on the backgroundProcessorDelay of
the manager's parent element (in this case it is the context). If this attribute is not
specified for the context, the Host attribute (the parent element of the context) is used.
If the Host does not specify this attribute, then the Engine background processor delay
is used.
In the default configuration, the backgroundProcessorDelay of the Engine is 60
seconds and the Host and the contexts do not explicitly configure the
backgroundProcessorDelay attribute. The in memory sessions are checked if they
are eligible for persistence every (60 X 6)=360 seconds. The number 6 is the value of
the processExpiresFrequency attribute of the persistence manager.
The following are the checks performed to decide if a session must be persisted to the
store or not:
1. If the time since the last access is greater than the value indicated by
maxIdleSwap, the session is persisted to the store and is removed from memory.
For more information on maxIdleSwap, see Table 3-21
.
2. If the number of in-memory sessions is greater than the number indicated by
maxActiveSessions, then the sessions that are idle for longer than the time
indicated by minIdleSwap are persisted to the store. In this case, after the
sessionValidCol Name of the database column, contained in
the specified session table, that contains a
flag indicating whether this swapped out
session is still valid or not.
valid
sessionMaxInact
iveCol
Name of the database column, contained in
the specified session table, that contains the
maxInactiveInterval property of this
session.
maxinactiveinte
rval
sessionLastAcce
ssedCol
Name of the database column, contained in
the specified session table, that contains the
lastAccessedTime property of this
session.
lastaccessed
Table 3-20. Attribute List for the Store Element (page 2 of 2)
Attribute Description Default value