Hi, We try to make a workaround for the following problems: 1.) memory management 2.) application update 3.) do not kill active sessions
Perhaps someone can comment on the startegy and answer some questions. Our environment: Tomcat 3.3 final with mod_jk Apache 1.3.19 on Solaris 2.7 Sparc Our problem: ever growing cache until memory runs out (clearly an application problem) plus soft updates to our application without killing actiove sessions The idea: when a certain ammount of memory is reached by the tomcat java process, start up a second Tomcat and route all new requests to the second instance while existing sessions should phase out on the first instance. If no more sessions are active on the original Tomcat, shut it down (currently we just shut it down 30 minutes after the second Tomcat started up) How to do it with mod_jk: We have two versions of a worker.properties. Before we start up our second tomcat, we switch a link to point to the other version. Both versions of the worker.property file have a loadbalancer worker defined: First version: worker.list=loadbalancer worker.ajp13-01.port=11009 worker.ajp13-01.host=tomcathost worker.ajp13-01.type=ajp13 worker.ajp13-01.lbfactor=1 <- important worker.ajp13-02.port=11019 worker.ajp13-02.host=tomcathost worker.ajp13-02.type=ajp13 worker.ajp13-02.lbfactor=0 <- important worker.loadbalancer.type=lb worker.loadbalancer.balanced_workers=ajp13-01, ajp13-02 Second version: worker.list=loadbalancer worker.ajp13-01.port=11009 worker.ajp13-01.host=tomcathost worker.ajp13-01.type=ajp13 worker.ajp13-01.lbfactor=0 <- important worker.ajp13-02.port=11019 worker.ajp13-02.host=tomcathost worker.ajp13-02.type=ajp13 worker.ajp13-02.lbfactor=1 <- important worker.loadbalancer.type=lb worker.loadbalancer.balanced_workers=ajp13-02, ajp13-01 We just try to switch the lbfactor from 1 to 0 for the first Tomcat and from 0 to 1 for the second Tomcat. after the switch we do a graceful restart of apache. but after this we still see new sessions beeing created on the first Tomcat now with lbfactor=0! Why? Question: why does it state in the workers.properties that lbfactor must be > 0 ? should we set it to 0.000001 instead of 0? Is this strategy completely nuts? Is there a better way to accomplish this? And yes, we need to fix our caching strategy ... but ... Best regards, Hans -- To unsubscribe: <mailto:[EMAIL PROTECTED]> For additional commands: <mailto:[EMAIL PROTECTED]> Troubles with the list: <mailto:[EMAIL PROTECTED]>
