Microprogrammed implementation of computer measurement techniques

Microprogramming has been accepted as a valuable tool in several areas of system design. However, microprogramming has not generally been used as a tool for evaluating the performance of computer systems. This paper describes the implementation of several techniques useful for program monitoring, debugging and system measurement using the microprogramable features of an existing computer system. The measurement system is completely transparent to almost all target programs. Given an existing system with a writable control store, a microprogram measurement system may be the most flexible, inexpensive, reliable, and high-speed means of monitoring the performance of a computer system.