Real-time, Unobtrusive, and Efficient Program Execution Tracing with Stream Caches and Last Stream Predictors

Abstract—This paper introduces a new hardware mechanism for capturing and compressing program execution traces unob-trusively in real-time. The proposed mechanism is based on two structures called stream cache and last stream predictor. We explore the effectiveness of a trace module based on these struc-tures and analyze the design space. We show that our trace module, with less than 600 bytes of state, achieves a trace-port bandwidth of 0.15 bits/instruction/processor, which is over six times better than state-of-the-art commercial designs. I