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# Acceleration - PowerPoint PPT Presentation

Acceleration. How to improve speed? At what costs?. T=Nq * CPI * Cycletime. Nq, Number of instructions CPI, Cycles Per Instruction Cycletime. Single Cycle Design. CPI = 1 Cycletime = Long (Longest path). Multiple Cycle. 1 < CPI < S Cycletime = Factor 1/S. Pipelined design.

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## PowerPoint Slideshow about ' Acceleration' - varian

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Presentation Transcript

• How to improve speed?

• At what costs?

• Nq, Number of instructions

• CPI, Cycles Per Instruction

• Cycletime

• CPI = 1

• Cycletime = Long (Longest path)

• 1 < CPI < S

• Cycletime = Factor 1/S

• CPI = 1, (Constant)

• Cycletime = Factor 1/S

• The total amount of work done in a given time

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INSTRUCTION

MEMORY

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DATA MEMORY

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• 5 stages, (IM, DE, EX, DM, WB)

• Writeback NOT in critical path

• Cut critical path by 4

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