Free Newsletters - Space News - Defense Alert - Environment Report - Energy Monitor
. Energy News .




ENERGY TECH
'No-sleep energy bugs' drain smartphone batteries
by Staff Writers
West Lafayette IN (SPX) Jun 14, 2012


File image.

Researchers have proposed a method to automatically detect a new class of software glitches in smartphones called "no-sleep energy bugs," which can entirely drain batteries while the phones are not in use. "These energy bugs are a silent battery killer," said Y. Charlie Hu, a Purdue University professor of electrical and computer engineering. "A fully charged phone battery can be drained in as little as five hours."

Because conserving battery power is critical for smartphones, the industry has adopted "an aggressive sleep policy," he said.

"What this means is that smartphones are always in a sleep mode, by default. When there are no active user interactions such as screen touches, every component, including the central processor, stays off unless an app instructs the operating system to keep it on."

Various background operations need to be performed while the phone is idle.

"For example, a mailer may need to automatically update email by checking with the remote server," Hu said.

To prevent the phone from going to sleep during such operations, smartphone manufacturers make application programming interfaces, or APIs, available to app developers. The developers insert the APIs into apps to instruct the phone to stay awake long enough to perform necessary operations.

"App developers have to explicitly juggle different power control APIs that are exported from the operating systems of the smartphones," Hu said. "Unfortunately, programmers are only human. They make mistakes when using these APIs, which leads to software bugs that mishandle power control, preventing the phone from engaging the sleep mode. As a result, the phone stays awake and drains the battery."

Findings are detailed in a research paper being presented during the 10th International Conference on Mobile Systems, Applications and Services, or MobiSys 2012, June 25-29 in the United Kingdom. The paper was written by doctoral students Abhinav Pathak and Abhilash Jindal, Hu, and Samuel Midkiff, a Purdue professor of electrical and computer engineering.

The researchers have completed the first systematic study of the no-sleep bugs and have proposed a method for automatically detecting them.

"We've had anecdotal evidence concerning these no-sleep energy bugs, but there has not been any systematic study of them until now," Midkiff said.

The researchers studied 187 Android applications that were found to contain Android's explicit power control APIs, called "wakelocks." Of the 187 apps, 42 were found to contain errors - or bugs - in their wakelock code. Findings showed the new tool accurately detected all 12 previously known instances of no-sleep energy bugs and found 30 new bugs in the apps.

The glitch has been found in interactive apps, such as phone applications and services for telephony on Android that must work even though the user isn't touching the phone. The app may fail to engage the sleep mode after the interactive session is completed.

Smartphone users, meanwhile, don't know that their phones have the bugs.

"You don't see any difference," Hu said. "You put it in your pocket and you think everything is fine. You take it out, and your battery is dead."

To detect bugs in the applications, the researchers modified a tool called a compiler, which translates code written in computer languages into the binary code that computers understand. The tool they developed adds new functionality to the compiler so that it can determine where no-sleep bugs might exist.

"The tool analyzes the binary code and automatically and accurately detects the presence of the no-sleep bugs," Midkiff said.

The Purdue researchers have coined the term "power-encumbered programming" to describe the smartphone energy bugs. Researchers concentrated on the Android smartphone, but the same types of bugs appear to affect other brands, Hu said.

Abstract on the research in this release is available here.

.


Related Links
MobiSys 2012
Purdue University
Powering The World in the 21st Century at Energy-Daily.com






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News





ENERGY TECH
New small solid oxide fuel cell reaches record efficiency
Richland WA (SPX) Jun 08, 2012
Individual homes and entire neighborhoods could be powered with a new, small-scale solid oxide fuel cell system that achieves up to 57 percent efficiency, significantly higher than the 30 to 50 percent efficiencies previously reported for other solid oxide fuel cell systems of its size, according to a study published in this month's issue of Journal of Power Sources. The smaller system, de ... read more


ENERGY TECH
TEPCO to buy 1 million tons LNG a year from Qatar

Nuclear and coal-fired electrical plants vulnerable to climate change

American Electric Power Pulls Billion Dollar Big Sandy Request

US and European energy supplies vulnerable to climate change

ENERGY TECH
US military to help Philippines monitor coastal waters

'No-sleep energy bugs' drain smartphone batteries

Tiny emirate could save gulf oil exports

France suspends Guiana offshore oil drilling

ENERGY TECH
South Korea partners for offshore wind

Change in air as Africa's biggest wind farm set for Kenya

Wind Powering An Island Economy

China Leads Growth in Global Wind Power Capacity

ENERGY TECH
Guardian Industries and Pythagoras Solar Announce Collaboration to Launch SunGuard PVGU

TE Introduces New Energy Solutions at Intersolar Europe

Calyxo increases capacity to 85 MW

Photovoltaic Cells Tap Underwater Solar Energy

ENERGY TECH
'Good progress' in global nuclear safety: IAEA

US, India see progress with nuclear deal

German utilities want 15 bn euros for nuclear exit: report

20,000 tonnes of uranium found in Jordan: joint venture

ENERGY TECH
Shell backs out of Brazil sugar-cane plans

Environmental benefit of biofuels is overestimated, new study claims

Steel-Strength Plastics That Are Clean And Green

Bigger refuges needed to delay pest resistance to biotech corn

ENERGY TECH
Shenzhou-9 full-system drill a success

Welcome Aboard Tiangong

Shenzhou-9 May Face Thunder, High Temps

Shenzhou 9 crews named in Chinese media

ENERGY TECH
Iraq 'green belt' front line in anti-desertification fight

Today's Climate More Sensitive to Carbon Dioxide Than in Past 12 Million Years

Sierra Nevada 200 year megadroughts confirmed

UN climate watchdog backs new greenhouse gas protocol




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement