Intel 7xx Servers, 170 Servers, AS/400 RISC Server manual

Appendix C. CPW and MCU Relative Performance Values for System i

This chapter details the relative system performance values:

yCommercial Processing Workload (CPW). For a detailed description, refer to Appendix A, “CPW Benchmark Description”. CPW values are relative system performance metrics and reflect the relative system capacity for the CPW workload. CPW values can be used with caution in a capacity planning analysis (e.g., to scale CPU-constrained capacities, CPU time per transaction). However, these values may not appropriately reflect the performance of workloads other CPW because of differing detailed characteristics (e.g., cache miss ratios, average cycles per instruction, software contention, I/O characteristics, memory requirements, and application performance characteristics). The CPW values shown in the tables are based on IBM internal tests. Actual performance in a customer environment may vary significantly. Use the “IBM Systems Workload Estimator” for assistance with sizing; please refer to Chapter 22.

yMail and Calendar Users (MCU). For a detailed description, refer to Chapter 11, “Domino for System i”. MCU values can be used to help size Domino environments for POWER5 and prior hardware. For new models, MCU values are not utilized or provided here.

yCompute Intensive Workload (CIW). For a detailed description, refer to Appendix A. CIW values are no longer utilized or provided here.

yUser-based Licensing. Many newer models utilize user-based licensing for i5/OS. For assistance in determining the required number of user licenses, see the product web pages (for example: http://www.ibm.com/systems/i/hardware or http://www.ibm.com/systems/power/hardware) . Note that user-based licensing is not a performance statement or a replacement for system sizing; instead, user-based licensing only enables appropriate user connectivity to the system. Application environments differ in their requirements for system resources. Use the “IBM Systems Workload Estimator” for assistance with sizing based on performance.

yRelative Performance metric for System p (rPerf). System i systems that run AIX can be expected to produce the same performance as equivalent System p models given the same memory, disk, I/O, and workload configurations. The relative capacity of System p is often expressed in terms of rPerf values. The definition and the performance ratings for System p can be found at:

y rPerf definition: http://www.ibm.com/systems/p/hardware/rperf.html

y rPerf table: http://www.ibm.com/systems/p/hardware/system_perf.html

IBM i 6.1 Performance Capabilities Reference - January/April/October 2008
© Copyright IBM Corp. 2008	Appendix C CPW, CIW and MCU for System i Platform	344