At the client place, we are upgrading the IVR application to OD7.1 (from DD5.1) and moving to Websphere from Apache Tomcat.
As part of the sizing, how do we arrive at the heap size range (max and initial). Also, any configuration tuning needs to be done at Websphere end so that we take the full advantage of the available heap size.

IVR application takes about 50k calls per day and the max number of concurrent calls is about 500 (during peak hours)

Please advice.

Regards,
Srini

The heap size is usually depending on how large your application is. You would need to follow any guidelines on Websphere and use the tools it provides to monitor the class instances and garbage collection in order to fine tune the performance and the JVM parameters.

Thanks Wilson!

monitoring the GC and class instances are to fine tune the heap size -- that is the next step. First step is to what value should we set during the initial installation /commissioning of websphere server.
Please advice.
current IVR application takes about 50k calls per day with a max concurrent calls of 500 during peak hours

Thanks,
Srini

Use defaults first.

Ok Wilson!

Thanks for your answers