Superlinear Speedup: Can speedup be greater than P with P processingelements?ParallelSpeedup.CacheeffectsSuperlinear.Working set effectsTypicalSuccessLinear.Happens in two ways:-UnfaircomparisonsSublinear-Memory effects#ProcessorsComputerArchitecture11
Computer Architecture Superlinear Speedup • Can speedup be greater than P with P processing elements? • Cache effects • Working set effects • Happens in two ways: – Unfair comparisons – Memory effects 11
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Computer Architecture Caveats of Parallelism (I) 12
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Computer Architecture Amdahl’s Law 13 Amdahl, “Validity of the single processor approach to achieving large scale computing capabilities, ” AFIPS 1967
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Computer Architecture Amdahl’s Law Implication 1 14
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Computer Architecture Amdahl’s Law Implication 2 15