What is Speedup?

Execution time before an improvement divided by the time after; a value of 2 means twice as fast.

Field: Performance Analysis

Speedup in the explanations

Questions that mention Speedup (12)

  1. If 90% of a program can be parallelized, what is the theoretical maximum speedup when it runs on an unlimited number of processors?
  2. How is speedup, which expresses a performance improvement, calculated?
  3. A part taking 50% of total time is made 4× faster. What is the overall speedup (Amdahl's law)?
  4. In a program processing large amounts of data, which improvement is most likely to give the largest speedup?
  5. Which is NOT a reason a parallel program fails to scale as cores are added?
  6. Which statement about pruning neural networks is correct?
  7. A CPU design change raises clock frequency 1.5× but also raises CPI 1.2× (instruction count unchanged). How many times faster is execution?
  8. You want to make an entire task 2× faster by speeding up only the part that takes 60% of the time. How many times faster must that part become?
  9. What idea does Gustafson's law express?
  10. What is the most appropriate method for examining a parallel program's scalability?
  11. Running in parallel on 8 cores is 6× faster than on 1 core. What is the parallel efficiency?
  12. When evaluating a claim that "the new method is 100× faster," what is most important to check?

Related terms

Amdahl's law Gustafson's law False sharing Pruning Cycles per instruction (CPI) Parallel efficiency Benchmark CPU time Flame graph Geometric mean

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