Results

The Cognos® BI and the WAS DayTrader workloads are executed in parallel in unconstrained and constrained CPU scenarios. A major question for this performance study is the impact on the Cognos BI transaction throughput and response times caused by competing workloads and how good throughput and response times can be guaranteed in such scenarios.

For this purpose, two z/VM® test scenarios were considered. The first scenario, z/VM fair share setup, ensures that all virtual CPUs for the z/VM guests have the same relative share. That means all guests get the same weight according to their number of virtual CPUs (see Control virtual machine CPU capacity).

The second scenario is described in two subtopics.

• VMRM parameters at first introduces the z/VM Resource Manager and its CPU management capabilities.
• VMRM - managing workload peaks then describes the test setup and presents the measurement results. In this scenario, VMRM is used to control the relative shares for the guests according to defined management goals. These CPU management goals should define a higher priority for the Cognos BI workload than for the competing workloads. As a result, the Cognos BI workload should run privileged in a constrained CPU environment (see z/VM Resource Manager (VMRM)).