Feeds

Researchers propose ‘overclock’ scheme for mobiles

Processing at a sprint to overcome tech limitations

Beginner's guide to SSL certificates

It’s getting increasingly difficult to pack enough processing power into mobile phone form factors, so US researchers are proposing a new scheme: seriously over-spec the processors, but only use their power when it’s needed.

The research paper, authored by scientists from the Universities of Pennsylvania and Michigan, suggests a scheme called “computational sprinting” – build mobile chips not with a couple of cores working hard all the time, but with as many as 16 cores, most of which are idle unless they’re needed.

The paper’s authors say that future smartphone development is running into a dual problem: shedding heat, and preserving battery life. While we’re not yet at the limit of transistor density, they say that “voltage scaling has stalled”.

For much of the history of the integrated circuit, smaller geometries that allow more transistors to be packed into less space are accompanied with lower operating voltage, which helps designers cope with the job of getting rid of the heat generated by all those extra transistors.

Without that, power density increases from one generation of processor to the next and in mobile devices, power (and cooling) rather than chip real estate becomes the barrier to higher performance.

Hence the “computational sprinting” described by the researchers. Their analysis looks at a system that spends most of its time operating a single core with 1W peak power, since most smartphones spend most of their time doing not very much. The system could, however, “burst up” to use all of its cores when necessary.

This, the paper states, is representative of the user experience with smart phones: “short bursts of intense computation punctuated by long idle periods waiting for user input” (El Reg: sounds like a quotation about war, for which I can’t find a good citation right now).

The whole chip could be fired up for the computationally-intensive task, even though this would momentarily exceed the power budget and heat dissipation capabilities of the device, because there’s a time lag between powering-up the processor cores and the extra heat generated. This “thermal capacitance” (also used by burst systems like Intel’s Turbo Boost technology), combined with usually “dark” silicon, could “result in an intense sprint with the potential to provide an order of magnitude improvement in responsiveness”, the authors state.

The paper, by Arun Raghavan and Milo Martin (University of Pennsylvania), and the University of Michigan’s Yixin Luo, Anuj Chandawalla, Marios Papaefthymiou, Kevin Pipe, Thomas Wenisch, was prepared for the 18th Symposium on High Performance Computer Architecture, and is available here. ®

Secure remote control for conventional and virtual desktops

More from The Register

next story
Mighty Blighty broadbanders beg: Let us lay cable in BT's, er, ducts
Complain to Ofcom that telco has 'effective monopoly'
BT said to have pulled patent-infringing boxes from DSL network
Take your license demand and stick it in your ASSIA
Yahoo! blames! MONSTER! email! OUTAGE! on! CUT! CABLE! bungle!
Weekend woe for BT as telco struggles to restore service
Fujitsu CTO: We'll be 3D-printing tech execs in 15 years
Fleshy techie disses network neutrality, helmet-less motorcyclists
Ofcom tackles complaint over Premier League footie TV rights
Virgin Media: UK fans pay the most for the fewest matches
FCC: Gonna need y'all to cough up $1.5bn to put broadband in schools
Kids need more fiber, says Wheeler, and you'll pay for it
prev story

Whitepapers

Designing and building an open ITOA architecture
Learn about a new IT data taxonomy defined by the four data sources of IT visibility: wire, machine, agent, and synthetic data sets.
How to determine if cloud backup is right for your servers
Two key factors, technical feasibility and TCO economics, that backup and IT operations managers should consider when assessing cloud backup.
Getting started with customer-focused identity management
Learn why identity is a fundamental requirement to digital growth, and how without it there is no way to identify and engage customers in a meaningful way.
Reg Reader Research: SaaS based Email and Office Productivity Tools
Read this Reg reader report which provides advice and guidance for SMBs towards the use of SaaS based email and Office productivity tools.
Website security in corporate America
Find out how you rank among other IT managers testing your website's vulnerabilities.