cpu - possible factors in slowing down a parallel program -



cpu - possible factors in slowing down a parallel program -

consider programme can run in parallel , moved single core quad core. speed 4-fold?

say not see expected speedup in program. can possible reasons? cache 1 reason if each core not have separate cache have problem. other issues?

one possible reason not see performance boost if work you're dividing on 4 processors small. if have 4 simple add-on operations you're sending separate processors, might take more time work of delegation 4 operations on 1 processor.

parallel-processing cpu

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