USENIX Association Proceedings of the 5th Symposium on Operating Systems Design and Implementation Boston, Massachusetts, USA December 9–11, 2002 THE ADVANCED COMPUTING SYSTEMS ASSOCIATION © 2002 by The USENIX Association All Rights Reserved For more information about the USENIX Association: Phone: 1 510 528 8649 FAX: 1 510 548 5738 Email:
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[email protected] [email protected] ARM Limited The University of Michigan 110 Fulbourn Road 1301 Beal Avenue Cambridge, UK CB1 9NJ Ann Arbor, MI 48109-2122 Abstract player, game machine, camera, GPS, even the wallet— into a single device. This requires processors that are Combining high performance with low power con- capable of high performance and modest power con- sumption is becoming one of the primary objectives of sumption. Moreover, to be power efficient, the proces- processor designs. Instead of relying just on sleep mode sors for the next generation communicator need to take for conserving power, an increasing number of proces- advantage of the highly variable performance require- sors take advantage of the fact that reducing the clock ments of the applications they are likely to run. For frequency and corresponding operating voltage of the example an MPEG video player requires about an order CPU can yield quadratic decrease in energy use.