Problem with File Based replication in Weblogic Express 10

Hi,

We have Web application (exploded war) file deployed on Weblogic Express 10, to
a Cluster of three Managed Servers (all three on different physical machines).

We are using File based session persistance in weblogic.xml

We have a shared location for all the three servers where we will be sharing the
Session data.

When we start the application, its works fine and is very fast, but after
sometime the application slows down.

Troubleshooting the Issue we found that its a problem with file based
replication. By using File based replication every user session is stored in
form of directory inside shared directory. So after sometime thousands of
directories are created inside the shared directory where the session
information is stored. So when we access the application, its waiting for lot of
time with Message Session Monitor .... (this is because its browsing through the
shared session storage directory for lot of time for session information as it
has lot of directories) and finally after a long time like 10 mins we get the
Application Home Page.

When we clean up all the saved sessions inside shared directory, the application
works fine, But we will see the same sometime later may be after 3 or 4 hours
when the shared session directory has lot of session information stored in it.

Is there a way to clean up the saved session information on file system as soon
as that user session is closed by using file based replication.

We cannot used Inmemory replication as our Appl doesnt support it.

Please advice as it is a major show stopper in our Production Mirror env.

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