Statistics for Parallelism and Abstraction Level in Digital Simulation

This paper presents statistics of several designs at four design abstraction levels - the instruction, behavioral, RTL, and gate levels. The data includes simulation time profiles, maximum speedup and limitations of parallelism, typical model evaluation times, event distributions, element intensities, and component counts for the four abstraction levels. This data is then used to analyze and evaluate several speed-up approaches: mixed-level simulation, parallel software simulators, parallel pipelined hardware accelerators, and decreased time resolution. The results show that element activity is around 0.1 to 0.5% at any particular time point. For the example circuits (3400 gates, 5000 gates, and 150,000 transistors), simulations show that parallelism can obtain speed-ups between 10-30. We found a factor of roughly ten speed-up between each of the abstraction levels.