Comparing Benchmarks Using Key Microarchitecture-Independent Characteristics

Understanding the behavior of emerging workloads is important for designing next generation microprocessors. For addressing this issue, computer architects and performance analysts build benchmark suites of new application domains and compare the behavioral characteristics of these benchmark suites against well-known benchmark suites. Current practice typically compares workloads based on microarchitecture-dependent characteristics generated from running these workloads on real hardware. There is one pitfall though with comparing benchmarks using microarchitecture-dependent characteristics, namely that completely different inherent program behavior may yield similar microarchitecture-dependent behavior. This paper proposes a methodology for characterizing benchmarks based on microarchitecture-independent characteristics. This methodology minimizes the number of inherent program characteristics that need to be measured by exploiting correlation between program characteristics. In fact, we reduce our 47-dimensional space to an 8-dimensional space without compromising the methodology's ability to compare benchmarks. The important benefits of this methodology are that (i) only a limited number of microarchitecture-independent characteristics need to be measured, and (ii) the resulting workload characterization is easy to interpret. Using this methodology we compare 122 benchmarks from 6 recently proposed benchmark suites. We conclude that some benchmarks in emerging benchmark suites are indeed similar to benchmarks from well-known benchmark suites as suggested through a microarchitecture-dependent characterization. However, other benchmarks are dissimilar based on a microarchitecture-independent characterization although a microarchitecture-dependent characterization suggests the opposite to be true