Report Number: CSL-TR-74-66
Institution: Stanford University, Computer Systems Laboratory
Title: Computer system performance measurement: instruction set processor
level and microcode level
Author: Svobodova, Liba
Date: June 1974
Abstract: Techniques based on hardware monitoring were developed to
measure computer system performance on the instruction set
processor level and the microcode level.
Knowledge of system behavior and system utilization at these
two levels is extremely valuable for design of new
processors. The reasons why such information is needed are
discussed and applicable measurement techniques for obtaining
necessary data are reviewed. A hardware monitor is a
preferable measurement tool since it can trace most of the
significant events attributed to these two levels without
introducing any artifact.
Described hardware monitoring techniques were implemented on
the S/370 Model 145 at Stanford University. Measurements
performed on the instruction set processor level were
concerned with determining execution frequencies on
individual instructions under normal system workload. The
microcode level measurements measured the number and the type
of S/370 Model 145 microwords executed in the process of
interpretation of an individual S/370 instruction and the
average execution time of each such instruction.
Implementation of each technique is described and the results
based on the outcome of performed measurements are presented.
Finally, effectiveness and ease of use of the discussed
techniques are considered.