Commonly Used Metrics for Performance Analysis - Power.org

Metrics for Performance Analysis2 The Execution PipelineThe POWER7 architecture, like most modern processors, can dispatch groups of machine instructions everycycle. Groups are dispatched into the execution pipeline in order and completed in order. Instructions orinternal operations in a group can execute out of order, and all instructions in a group must finish before agroup can complete (“retire”). This is the essence of the “out-of-order” nature of the POWER7 architecture.Figure 2-1 is a standard block diagram of the POWER7 core’s structure and the execution pipeline:Figure 2-1 POWER7 core structure and execution pipeline detailsConcentrating on the CPI stack, a simplified execution pipeline is presented in Figure 2-2.Copyright ©2011 IBM Corporation Page 6 of 52