The Roots and Evolution of the RMF and SMF for Mainframe Performance Data (Part 1)

George Dodson

By George Dodson

This blog originally appeared as an article in Enterprise Executive.

Computer professionals have been interested in determining how to make computer applications run faster and determine the causes of slow running applications for more than 50 years. In the early days, computer performance was in some ways easy because electronic components were soldered in place. To understand what was happening at any point in the circuitry, we simply attached a probe and examined the electronic wave information on an oscilloscope.

Eventually, we were able to measure activity at key points in the computer circuitry to determine things like CPU Utilization, Channel Utilization and Input/Output response times. However, this method still had many shortcomings. First, the number of probes was very small, usually less than 40. Secondly, this method gives no insight into operating system functions or application operations that may be causing tremendous overhead. And of course, when integrated circuits were developed, the probe points went away.

In 1966 I joined an IBM team that was focusing on a better way to conduct benchmarks in what was then named an IBM Systems Center. Customers considering computer upgrades would come to our data center to determine how their programs would operate on newly released hardware. But it was simply not possible to host every customer in this way.

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