IBM recommendations
IBM recommends starting by classification, and running WLM in passive mode to collect the resource use profile. It is important to run the wlmcheck program to validate the configuration.
Having that data, the next steps are assigning small changes to the processor shares, and then monitoring the effects. This stage can be repeated until the desired control is obtained. It allows for rollback if the rules cause service problems.
WLM has a special mode of operation that ignores memory and disk bandwidth, which may suffice for a WebSphere Application Server service with ample memory. However, if the total demand for memory from background tasks and WebSphere Application Server exceeds what is available, then memory minimums may be worthwhile. The use of memory maximums is not recommended, as they can cause paging even if the LPAR is undercommitted.
As described in 8.4, AIX Workload Management feature, you can define several WebSphere superclasses, and within them up to 10 application subclasses. IBM recommends keeping the number of different classes relatively small; that is, use a few application classes over and above the supplied System and Default classes.