Phase-Guided Small-Sample Simulation

Detailed cycle-accurate simulation is a critical component of processor design. However, with the increasing complexity of modern processors and application workloads, full detailed simulation is prohibitively slow and thereby severely limits design space exploration. Sampled simulation techniques eliminate the need for full simulation by simulating in detail a very small but representative subset of a target application's overall execution. Two effective and accurate sampling techniques are phase-based simulation and small-sample simulation. Both of these techniques have been adopted by the architecture design and simulation communities for research. However, both techniques were derived using a single benchmark evaluation suite and promote the same sampling method for all applications. Alternatively, an execution-aware sampling-based simulation technique can adapt during execution characteristics of the individual application being simulated and achieve the most efficient and accurate simulation acceleration. To evaluate the impact of application characteristics on simulation approaches, we compare several simulation techniques using the SpedOOO benchmark suite. Our results yield key conclusions about combining the strengths of previous simulation techniques into a single approach: (PGSS) phase-guided small-sample simulation. PGSS adapts sampling to the characteristics of the application, thereby achieving high sampling accuracy and requiring an order of magnitude less detailed simulation time than previous techniques