Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Computer scientists leverage dark silicon to improve smartphone battery life

01.09.2010
A new smartphone chip prototype under development at the University of California, San Diego will improve smartphone efficiency by making use of “dark silicon” – the underused transistors in modern microprocessors. On August 23, UC San Diego computer scientists presented GreenDroid, the new smartphone chip prototype at the HotChips symposium in Palo Alto, CA.
Dark silicon refers to the huge swaths of silicon transistors on today’s chips that are underused because there is not enough power to utilize all the transistors at the same time. The new GreenDroid chip prototype from computer scientists at UC San Diego will deliver improved performance through specialized processors fashioned from dark silicon. These processors are designed to run heavily used chunks of code, called “hot code,” in Google’s Android smartphone platform.

Computer science professors Michael Taylor and Steven Swanson from the Department of Computer Science and Engineering (CSE) at the UC San Diego Jacobs School of Engineering are leading the project.

“This is an exciting time for UCSD. Our students are designing a real multicore processing chip, in an advanced technology, that is simultaneously advancing the state-of-the art in both smartphone and processor design. This marks the first of what I hope is many such chips that will come out of the UCSD research community,” said Taylor.

The GreenDroid presentation at HotChips caught the attention of IEEE Spectrum, EETimes and LightReading, which all ran stories.

While chip makers can now make similar types of specialized processors by hand, the UC San Diego computer scientists developed a fully automated system. It generates blueprints for specialized processors, called conservation cores, from source code extracted from applications.

GreenDroid conservation cores use 11 times less energy per instruction than an aggressive mobile application processor. Accounting for code running outside the conservation core still results in an increase in efficiency of 7.5 times compared to an aggressive mobile application processor, according to the computer scientists’ HotChips presentation.

“Smartphones are a perfect match for our approach, since users spend most of their time running a core set of applications, and they demand long battery life. As mobile applications become more sophisticated, it’s going to be harder and harder to meet that challenge. Conservation cores offer a solution that exploits a resource that will soon be quite plentiful – dark silicon,” said Swanson.

Conservation cores also incorporate focused reconfigurability that allows them to adapt to small changes in the target application while still delivering efficiency gains.

Dark Silicon

This work is motivated by the growing problem of dark silicon, which refers to transistors on microprocessors that are forced to remain off most of the time because of power constraints

“We don’t have enough power to use all the transistors at once – that is the ‘utilization wall,’” said UC San Diego computer science graduate student Nathan Goulding who presented the team’s GreenDroid chip at HotChips. Goulding led GreenDroid development, which is one part of the larger conservation core project.

“The utilization wall will change the way everyone builds processors,” the computer scientists reported in their HotChips talk.

If this utilization wall problem is not solved, more transistors on computer chips will not necessarily lead to improved performance or problem solving capacity in each new chip generation.

Automated Hardware Maker

As a real-world prototype, the computer scientists from the UC San Diego Jacobs School of Engineering used dark silicon to build specialized circuits for specific tasks frequently performed by popular smartphone applications such as Web browsers, email software and music players. The computer scientists asked ‘where does most of the computation happen?’

They took answers to this question, and fed the relevant code into their automated tool chain.

“A chip that does MP3 decoding…people can build specialized logic for this by hand, but it’s an enormous amount of effort and this doesn’t scale well. Our approach is automated,” said Goulding.

The computer scientists input pieces of code shared by multiple software applications for Android phones. The output at the end of the automated chain is a blueprint for specialized hardware. This specialized hardware will only execute some regions of the software code. The rest of the code, known as “cold code”, is executed by the phone’s general processor.

The computer scientists chose a smartphone for their chip prototype because mobile handsets are the new dominant computing platform. “Smartphones are going to be everywhere,” said Goulding, “We said to ourselves, ‘let’s make a prototype chip that saves energy on Android phones.’”

The HotChips slides and the full list of authors are below.

GreenDroid: A Mobile Application Processor for Silicon’s Dark Future, Nathan Goulding, Jack Sampson, Ganesh Venkatesh, Saturnino Garcia, Joe Auricchio, Jonathan Babb*,Michael Taylor, andSteven Swanson, Proceedings of HotChips, 2010.

*Jonathan Babb is at CSAIL, Massachusetts Institute of Technology

Related work from the team: Conservation Cores: Reducing the Energy of Mature Computations, Ganesh Venkatesh, Jack Sampson, Nathan Goulding, Saturnino Garcia, Vladyslav Bryksin, Jose Lugo-Martinez,Steven Swanson, andMichael Bedford Taylor, ASPLOS '10: Proceeding of the 15th international conference on Architectural support for programming languages and operating systems, 2010.

Daniel Kane | EurekAlert!
Further information:
http://www.ucsd.edu

More articles from Power and Electrical Engineering:

nachricht Researchers take next step toward fusion energy
16.11.2017 | Texas A&M University

nachricht Desert solar to fuel centuries of air travel
16.11.2017 | SolarPACES

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

NASA detects solar flare pulses at Sun and Earth

17.11.2017 | Physics and Astronomy

NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures

17.11.2017 | Health and Medicine

The importance of biodiversity in forests could increase due to climate change

17.11.2017 | Studies and Analyses

VideoLinks
B2B-VideoLinks
More VideoLinks >>>