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Timer value: TICK2

TICK2 confirms that the absolute values returned by the computer clock are correct, by comparing its measurement of a given time interval with that of an external wall-clock (actually the benchmarker's wristwatch). Parallel benchmark performance can only be measured using the elapsed wall-clock time, because the objective of parallel execution is to reduce this time. Measurements made with a CPU-timer (which only records time when its job is executing in the CPU) are clearly incorrect, because the clock does not record waiting time when the job is out of the CPU. TICK2 will immediately detect the incorrect use of a CPU-time-for-this-job-only clock. An example of a timer that claims to measure elapsed time but is actually a CPU-timer, is the returned value of the popular Sun UNIX timer ETIME. TICK2 also checks that the correct multiplier is being used in the computer system software to convert clock ticks to true seconds.

TICK2 exists and forms part of release 2.2 and later of the Genesis benchmarks [13].



top500@rz.uni-mannheim.de
Tue Nov 14 15:43:14 PST 1995