Thermal-aware vacation and rate adaptation for network packet processing

As processor power density increases, thermal and power control becomes critical for packet processing on a processor. In “run-to-finish” applications, power consumption is stable and temperature simply rises to saturation point and then stabilizes. But, network applications feature ON/OFF execution pattern, which causes frequent temperature and power consumption changes in the processor. We propose a thermal aware scheduler, TrafficLight, which achieves power saving by employing vacation and rate adaptation techniques. We implement these through the idle states (C-state) provided by the OS in a CPU and show their effectiveness through experimental data. Then we build power, thermal and latency models based on the vacation queuing theory, which estimates the performance of our proposed techniques. Finally, we design, implement and evaluate an on-line algorithm to dynamically choose the proper power/thermal management technique based on the traffic variation. The technique maintains the processor temperature below the temperature constraint and achieves power saving. To the best of our knowledge, this is the first work to provide the theoretical analysis as well as the experimental results for the vacation and rate adaptation schemes considering power, temperature and latency in the packet processing on a general purpose processor.