Philip Lewis Rosenfeld

Fractal nature of software-cache interaction

This paper uses fractals to model the clustering of cache misses. The clustering of cache misses can be quantified by a single number analog to a fractional dimension, and we are intrigued by the possibility that this number can be used as a measure of software complexity. The essential intuition is that cache misses are a direct reflection of changes in locality of reference, and that complex software requires more frequent (and larger) changes in this locality than simple software. The cluster dimension provides a measure (and perhaps the basis for a model) of the intrinsic differences between workloads. In this paper, we focus on cache miss activity as a discriminate between interactive and batch environments.

Integration of machine organization and control program design: review and direction

This paper discusses the relationship between machine organization and control program design in high-end commercial computer systems. The criterion is cost/performance, subject to achieving an acceptable performance level. A brief discussion of the environment expected for the design and operation of high-end commercial computer systems is outlined, followed by a discussion of machine organization techniques which are classified and reviewed to permit a qualitative evaluation of the degree to which control program intent is exploited in machine organization. The thesis is developed next, using a hierarchical model which illustrates the contention that architecture has acted as a barrier to communication between the control program and machine organization. Examples of techniques that exploit knowledge of the intent of the control program and comments on the methodology that might be used to investigate such techniques follow. Directions for further research are then proposed.