Performance modeling for hardware thread-level speculation

Abstract

This paper presents a preliminary performance model for hardware Thread-Level Speculation (TLS) in the IBM Blue Gene/Q computer. The model analyzes the TLS behavior and its overhead. We model the scenario when there are 0, 1 and 2 conflicts. The model shows good performance prediction and is verified with experiments. This study helps to understand potential gains from using special purpose TLS hardware to accelerate the performance of codes that, in a strict sense, require serial processing to avoid memory conflicts.