Hyung Beom Jang, Junhee Lee, Joonho Kong, Taeweon Suh, and Sung Woo Chung, "Leveraging Process Variation for Performance and Energy: In the Perspective of Overclocking", IEEE Transactions on Computers, vol.63, no. 5, pp. 1316-1322, May 2014.
Process variation is one of the most important factors to be considered
in recent microprocessor design, since it negatively affects
performance, power, and yield of microprocessors. However, by leveraging
process variation, overclocking techniques can improve performance. As
microprocessors have substantial clock cycle time margin for yield,
there is enough room for performance improvement by overclocking
techniques. In this paper, we adopt the F-overclocking technique, which
increases clock frequency without changing supply voltage. Our
experimental results show that the F-overclocking technique
significantly improves performance as well as energy consumption. In
addition, the F-overclocking technique is superior to the conventional
overclocking technique which increases clock frequency and supply
voltage together in the perspective of energy efficiency and
reliability, showing similar performance improvement. Furthermore, we
propose an adaptive overclocking controller which dynamically applies
the F-overclocking technique based on the application characteristics.
By adopting our adaptive overclocking controller, we further minimize
the reliability loss caused by the F-overclocking technique.