“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.
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!
ISFH-CalTeC is “designated test centre” for the confirmation of solar cell world records
16.01.2018 | Institut für Solarenergieforschung GmbH
A water-based, rechargeable battery
09.01.2018 | Empa - Eidgenössische Materialprüfungs- und Forschungsanstalt
What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...
For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.
Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...
At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.
No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...
Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.
Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...
The oceans are the largest global heat reservoir. As a result of man-made global warming, the temperature in the global climate system increases; around 90% of...
08.01.2018 | Event News
11.12.2017 | Event News
08.12.2017 | Event News
18.01.2018 | Life Sciences
18.01.2018 | Life Sciences
18.01.2018 | Earth Sciences