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At the end of the simulation, the
PipelineModel generates a Cycles Per Instruction (CPI) value along with other performance data. You can use this for further analysis.
Elapsed time: 8 seconds Instructions per second: 484186 Simulated CPU speed: 1.484186 MHz CPU cycles: 5159984 RAW stalls: 3551018 Instructions issued: 3873492 Instructions retired: 3873491 Loads executed: 921403 Stores executed: 923306 IPC: 0.750679 CPI: 1.33213
The CPI value is the primary metric that measures the performance of workloads, where:
CPI = cycles elapsed / instructions retired
The lower the CPI, the better the performance. As a general indication, a CPI of 0.5 on a dual-issue, in-order or out-of-order processor means that an instruction takes 0.5 cycles to complete. In this case, the pipeline units are maximized and no latencies are generated.
Conversely, performance can be measured in Instructions Per Cycle (IPC), where:
IPC = instructions retired / cycles elapsed
The higher the IPC, the better the performance. As a general indication, an IPC of two on a dual issue, in-order or out-of-order processor means that on average, two instructions commit in each cycle.