Steven Wayne White

POWER2: next generation of the RISC System/6000 family

Since its announcement, the IBM RISC System/6000@ processor has characterized the aggressive instruction-level parallelism approach to achieving performance. Recent enhancements to the architecture and implementation provide greater superscalar capability. This paper describes the architectural extensions which improve storage reference bandwidth, allow hardware square-root computation, and speed floating-point-to-integer conversion. The implementation, which exploits these extensions and doubles the number of functional units, is also described. A comparison of performance results on a variety of industry standard benchmarks demonstrates that superscalar capabilities are an attractive alternative to aggressive clock rates.

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.

POWER2: architecture and performance

A dichotomy exists among the various approaches to achieving performance in the workstation and server markets. Some implementations aggressively pursue high clock rate goals, often by settling for less instruction-level parallelism. In contrast, IBM workstations have been well-known for supporting high degrees of concurrency. POWER2 (Performance Optimized With Enhanced RISC) based RISC System/6000 workstations further widen the gap between the instruction-level parallelism and clock rate approaches. This paper describes the architecture and performance aspects of these new systems.<<ETX>>

A parallel computational approach using a cluster of IBM ES/3090 600Js for physical mapping of chromosomes

A standard technique for mapping a chromosome is to randomly select pieces, to use restriction enzymes to cut these pieces into fragments, and then to use the fragments for estimating the probability of overlap of these pieces. The authors describe a computational approach which has been used in the mapping of human chromosome 16 at Los Alamos National Laboratory. In particular, they describe 6-way and clustered implementations of an IBM Clustered Fortran program for detection of fragment overlap, with specific attention paid to problem partitioning, task structure, synchronization, and other factors which allow this type of code to perform well on a cluster of shared-memory multiprocessors. Measurements for one, six, and twelve processors for reduced problem sizes are included.<<ETX>>

Clustering IBM Enterprise System/3090 computers for parallel execution of FORTRAN programs

Two IBM Enterprise System/3090TM Model SOOJ computer systems, each with six processors capable of executing vector and scalar instructions, have been connected into a cluster for parallel execution of single FORTRAN programs. The clustering Is achieved through a combination of software and hardware. When enabled for parallel execution and allowed to use all twelve processors in the cluster, FORTRAN programs have run as much as 11.7 times faster than when run on a single processor. The combined hardware and software technology Is called IBM Clustered FORTRAN. It was achieved by modifying existing technology quickly to provide new capabilities. This paper discusses the modifications and the motivations behind them. It summarizes the performance of several applications executed with Clustered FORTRAN. Finally, it describes how clustering has been used to improve performance in novel ways.