POWER3: The next generation of PowerPC processors

The POWER3 processor is a high-performance microprocessor which excels at technical computing. Designed by IBM and deployed in various IBM RS/6000® systems, the superscalar RISC POWER3 processor boasts many advanced features which give it exceptional performance on challenging applications from the workstation to the supercomputer level. In this paper, we describe the microarchitectural features of the POWER3 processor, particularly those which are unique or significant to the performance of the chip, such as the data prefetch engine, nonblocking and interleaved data cache, and dual multiply-add-fused floating-point execution units. Additionally, the performance of specific instruction sequences and kernels is described to quantify and further illuminate the performance attributes of the POWER3 processor.