Weblogic81 + oracle

[tgh_china]

I deployed my web application to weblogic server which is worked under cluster enviroment. I use oracle database.
my weblogic configuration is like following in weblogic.xml

<!DOCTYPE weblogic-web-app PUBLIC "-//BEA Systems, Inc.//DTD Web Application 8.1//EN" "http://www.bea.com/servers/wls810/dtd/weblogic810-web-jar.dtd">



<weblogic-web-app>



<session-descriptor>

<session-param>

<param-name>PersistentStoreType</param-name>

<param-value>jdbc</param-value>

</session-param>

<session-param>

<param-name>PersistentStorePool</param-name>

<param-value>SANetPool</param-value>

</session-param>

[color=#FF0000] <session-param>

<param-name>PersistentStoreTable</param-name>

<param-value>wl_servlet_sessions</param-value>

</session-param>

</session-descriptor>

<jsp-descriptor>

<jsp-param>

<param-name>compileCommand</param-name>

<param-value>javac</param-value>

</jsp-param>

<jsp-param>

<param-name>keepgenerated</param-name>

<param-value>true</param-value>

</jsp-param>

<jsp-param>

<param-name>debug</param-name>

<param-value>true</param-value>

</jsp-param>

</jsp-descriptor>



<charset-params>

<input-charset>

<resource-path>/*</resource-path>

<java-charset-name>UTF-8</java-charset-name>

</input-charset>

</charset-params>


<context-root>/</context-root>



</weblogic-web-app>[/color]

but my DBA report some problem to me :
Due to the activity the archive logs have been filling up extremely fast, 8GB of archive logs were generated alone for the activity starting this morning 8am onwards and we have traced the sql statement responsible.

Pls find the statement below and advise what activity is triggering the statement.

update wl_servlet_sessions set wl_session_values = :1, wl_is_new = :2, wl_is_valid = :3, wl_access_time = :4, wl_max_inactive_interval = :5 where wl_id = :6 and wl_context_path = :7


Now my question is , why the archive logs file so big? when the above sql will be triggered?