1. A method for generating an analysis of modifications to a system resource of a target computer system that would result in improved performance during execution of computer programs on the target computer system, the execution of the computer programs placing an actual workload on the target computer system, the method comprising the computer-implemented steps of: collecting performance characteristics of system resources of the target computer system; collecting a set of actual performance measurements of the target computer system during execution of the computer programs on the target computer system; for each of the plurality of the test workloads, generating a set of predicted performance measurements that would result when the test workload is placed on the target computer system based on the collected performance characteristics of the target computer system; determining the set of predicted performance measurements that most closely matches the set of actual performance measurements, wherein the test workload that when placed on the target computer system would result in the determined set of predicted performance measurements is the workload that most probably represents the actual workload; identifying a system resource that is a bottleneck during execution of the computer programs based on the set of predicted performance measurements that most closely matches the set of actual performance measurements; selecting a system resource that can be modified to reduce utilization of the bottleneck system resource; and generating a set of predicted performance measurements that would result when the test workload that most probably represents the actual workload is placed on the target computer system based on the collected performance characteristics of the target computer system with the selected system resource modified to reduce utilization of the bottleneck system resource.