This white paper provides a basis for parameter and application tuning for IBM WebSphere Portal for Multiplatform, for Linux on System Z, and z/OS V188.8.131.52. Remember that both tuning and capacity are affected by many factors, including the workload scenario and the performance measurement environment. For tuning, the objective of this paper is not to recommend that you use the values we used when measuring our scenarios, but to make you aware of those parameters used in our configuration. When tuning your individual systems, it is important to begin with a baseline, monitor the performance metrics to determine if any parameters should be changed and, when a change is made, monitor the performance metrics to determine the effectiveness of the change.
IBM WebSphere Portal Performance Tuning Guide