Power Management

Vol. 1 No. 7 – 10-01-2003

Power Management


Reconfigurable Future

The Ability to Produce Cheaper, More Compact Chips is a Double-edged Sword.

by Mark Horowitz

Getting Gigascale Chips: Challenges and Opportunities in Continuing Moore's Law

Processor performance has increased by five orders of magnitude in the last three decades, made possible by following Moore's law - that is, continued technology scaling, improved transistor performance to increase frequency, additional (to avoid repetition) integration capacity to realize complex architectures, and reduced energy consumed per logic operation to keep power dissipation within limits. Advances in software technology, such as rich multimedia applications and runtime systems, exploited this performance explosion, delivering to end users higher productivity, seamless Internet connectivity, and even multimedia and entertainment.

by Shekhar Borkar

The Inevitability of Reconfigurable Systems

The introduction of the microprocessor in 1971 marked the beginning of a 30-year stall in design methods for electronic systems. The industry is coming out of the stall by shifting from programmed to reconfigurable systems. In programmed systems, a linear sequence of configuration bits, organized into blocks called instructions, configures fixed hardware to mimic custom hardware. In reconfigurable systems, the physical connections among logic elements change with time to mimic custom hardware. The transition to reconfigurable systems will be wrenching, but this is inevitable as the design emphasis shifts from cost performance to cost performance per watt. Here's the story.

by Nick Tredennick, Brion Shimamoto

Energy Management on Handheld Devices

Handheld devices are becoming ubiquitous and as their capabilities increase, they are starting to displace laptop computers - much as laptop computers have displaced desktop computers in many roles. Handheld devices are evolving from today's PDAs, organizers, cellular phones, and game machines into a variety of new forms. Although partially offset by improvements in low-power electronics, this increased functionality carries a corresponding increase in energy consumption. Second, as a consequence of displacing other pieces of equipment, handheld devices are seeing more use between battery charges. Finally, battery technology is not improving at the same pace as the energy requirements of handheld electronics. Therefore, energy management, once in the realm of desired features, has become an important design requirement and one of the greatest challenges in portable computing, and it will remain so for a long time to come.

by Marc A Viredaz, Lawrence S Brakmo, William R Hamburgen

Making a Case for Efficient Supercomputing

A supercomputer evokes images of "big iron" and speed; it is the Formula 1 racecar of computing. As we venture forth into the new millennium, however, I argue that efficiency, reliability, and availability will become the dominant issues by the end of this decade, not only for supercomputing, but also for computing in general.

by Wu-chun Feng

Modern System Power Management

The Advanced Configuration and Power Interface (ACPI) is the most widely used power and configuration interface for laptops, desktops, and server systems. It is also very complex, and its current specification weighs in at more than 500 pages. Needless to say, operating systems that choose to support ACPI require significant additional software support, up to and including fundamental OS architecture changes. The effort that ACPI's definition and implementation has entailed is worth the trouble because of how much flexibility it gives to the OS (and ultimately the user) to control power management policy and implementation.

by Andrew Grover

The Big Bang Theory of IDEs

Remember the halcyon days when development required only a text editor, a compiler, and some sort of debugger (in cases where the odd printf() or two alone didn't serve)? During the early days of computing, these were independent tools used iteratively in development's golden circle. Somewhere along the way we realized that a closer integration of these tools could expedite the development process. Thus was born the integrated development environment (IDE), a framework and user environment for software development that's actually a toolkit of instruments essential to software creation. At first, IDEs simply connected the big three (editor, compiler, and debugger), but nowadays most go well beyond those minimum requirements. In fact, in recent years, we have witnessed an explosion in the constituent functionality of IDEs.

by Caspar Boekhoudt

Reading, Writing, and Code

Forty years ago, when computer programming was an individual experience, the need for easily readable code wasn't on any priority list. Today, however, programming usually is a team-based activity, and writing code that others can easily decipher has become a necessity. Creating and developing readable code is not as easy as it sounds.

by Diomidis Spinellis


A Conversation with Dan Dobberpuhl

The computer industry has always been about power. The development of the microprocessors that power computers has been a relentless search for more power, higher speed, and better performance, usually in smaller and smaller packages. But when is enough enough?


Wireless Networking Considered Flaky

You know what bugs me about wireless networking? Everyone thinks it's so cool and never talks about the bad side of things. Oh sure, I can get on the 'net from anywhere at Usenix or the IETF (Internet Engineering Task Force), but those are _hostile_ _nets_. Hell, all wireless nets are hostile. By their very nature, you don't know who's sharing the ether with you. But people go on doing their stuff, confident that they are OK because they're behind the firewall.

by Eric Allman


Stand and Deliver: Why I Hate Stand-Up Meetings

Stand-up meetings are an important component of the 'whole team', which is one of the fundamental practices of extreme programming (XP).

by Phillip A Laplante