Http Session Tuning - Write Content

You can configure which session data is written to the database or to another WebSphere instance, depending on whether you are using database peresistent session or memory to memory replication. The following options are available for tuning what is to be written back:

  • Only updated session attributes: Write only session data properties that have been updated through setAttribute method and removeAttribute method

  • Write All: Write all session data properties.The Write all setting might benefit servlet and JSP writers who change Java objects’ states that reside as attributes in HttpSession and do not call HttpSession.setAttribute method. However, the use of Write all could result in more data being written back than is necessary. If this situation applies to you, consider combining the use of Write all with Time-based write to boost performance overall

With either Write Contents setting, when a session is first created, complete session information is written, including all of the objects bound to the session. When using database session persistence, in subsequent session requests, what is written to the database depends on whether a single-row or multi-row schema has been set for the session database,

  • Write changed

    • Behavior with single-row schema:If any session attribute is updated, all objects bound to the session are written.

    • Behavior with multirow schema:Only the session data modified through setAttribute method or removeAttribute method calls is written.

  • Write All

    • Behavior with single-row schema: All bound session attributes are written.

    • Behavior with multirow schema: All session attributes that currently reside in the cache are written. If the session has never left the cache, all session attributes are written.

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