Programmers figured that whatever code they wrote would run at least 50 percent faster on a 1995 machine and 50 percent faster still on a 96 system .Code would continue as it always had, with instructions designed to be executed one after the other.
It's not that old, single-core CPU's weren't already doing some parallel processing. When Olukotun began his work, most microprocessors had a super scalar architecture. In the super scalar scheme, the CPU contained many replicated components, such as arithmetic units. Individual instructions would be parceled out to the waiting components. Scaling up such instruction-level parallelism mean building in more and more such components as the years rolled by.
If you combined that with the delays inherent in the jumble of interconnects among all those parts, it seemed a losing proposition. Doug Burger and Stephen Cackler, both computer scientists at the University of Texas, Austin, put a finer point on it later in the decade, conniving that instead of the 50 percent improvements everyone had gotten used to, the computing industry should start thinking 12.5 percent. And 12.5 percent isn't much of an explanation to buy a new computer, is it?
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