[OT] Clustering / Session Replication

[Jan Zimmek <jz...@morelogs.de>]

Hi,

I read an article about clustering in tomcat on theserverside.com, but have some questions about it.

There is a statement to use "In-Memory"-Replication in favour of "Database/Filesystem"-Replication to avoid problems like (speed, external dependencies, ...).

Most of our projects make use of gui-components like trees, pager and pagecontrols, whose state are stored in the HttpSession-Object. Depending on the project, the amount of used memory for these objects can be really huge ( in a equivalent php version, a serialized session can be up to 1mb ).

Would this means, is that 200 concurrent HttpSessions ( each one ~ 1mb ) would be replicated to each Tomcat-Server in my cluster and therefore each server requires ~ 200mb RAM to hold all concurrent HttpSession-Objects when using "In-Memory"-Replication ?

Are there any mechanisms to share those huge HttpSessions over several servers without the needed RAM of ~200mb per server ?


Any comment would be really appreciated.


regards,
Jan Zimmek