Example: Choosing a topology for better performance
WAS provides various Workload Management (WLM) topologies. The following case study uses two topologies, Topology A and Topology B to show how the type of topology you choose can affect performance. In the case study, Topology A can improve performance from 10%-20% more than Topology B. You can see performance increase by using the J2EE benchmark Trade, which is included in this release.
Topology A contains a Web server and a WAS plug-in to a cluster of WASs. Each cluster member contains a Web container and EJB container. Topology B includes a Web server, a plug-in, and one Web container to a cluster of EJB containers. In both topologies, the Object Request Broker pass-by-reference is selected and the backend database is on a dedicated machine.
Topology A has an advantage because the Web container and EJB container are running in a single JVM. In Topology B, the Object Request Broker pass-by-reference option is ignored between the Web container cluster member and the EJB container member. In Topology A, the EJB container uses the same thread passed from the Web container. The request does not have to be passed from one thread in one JVM to another thread in another JVM.
Also, if the processor utilization of the cluster member machines is near 100% you can add more members. If the Web server box is not running at capacity and the Web container processing is not heavy, try freeing the processor on the other members by moving to Topology B.
In this test environment, Topology A had the advantage, however, many factors related to the application and environment can influence results.
See AlsoTuning performance parameter index