Tohru Ishihara

Nagoya University, Japan

Maximizing Energy-Efficiency of Dual-OS Platforms through DVFS Virtualization

Abstract

A dual-OS platform helps efficiently develop mixed-criticality systems by taking full advantages of both real-time OS (RTOS) and general-purpose OS (GPOS). RTOS is generally suitable for developing small yet reliable and secure real-time applications while GPOS is suited to develop large and complicated yet non-real-time applications by exploiting rich libraries. Although the dual-OS platform attracts increasing attention, it often suffers from energy inefficiency in the GPOS because of a conservative speed control for guaranteeing real-time responses of the RTOS. This talk presents a method named DVFS virtualization, which allows independently running multiple DVFS policies dedicated for the RTOS and GPOS, respectively. The evaluation experiment using a commercial processor board showed that the proposed hardware could change the supply voltage within 500 ns and reduce the energy consumption by more than 50% compared to existing dual-OS platforms.

Biography

Tohru Ishihara received his Dr.Eng. degree in computer science from Kyushu University in 2000. For the next three years, he was a Research Associate in the University of Tokyo. From 2003 to 2005, he was with Fujitsu Laboratories of America as a Research Staff of an Advanced CAD Technology Group. From 2005 to 2011, he was with Kyushu University as an Associate Professor. For the next seven years he was with Kyoto University. In October 2018, he joined Nagoya University where he is currently a Professor in the Department of Computing and Software Systems. His research interests include low-power design methodologies and power management techniques for embedded systems. Dr. Ishihara is a member of the IEEE, ACM, IPSJ and IEICE.