Subscribe free to our newsletters via your
. 24/7 Space 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
UA Lunar-Mining Team Wins National Contest

NASA Lunar Spacecraft Complete Prime Mission Ahead of Schedule

NASA Offers Guidelines To Protect Historic Sites On The Moon

Neil Armstrong gives rare interview - to accountant

ENERGY TECH
Impact atlas catalogs over 635,000 Martian craters

e2v imaging sensors launched into space on NASA mission to Mars

NASA Mars Rover Team Aims for Landing Closer to Prime Science Site

NASA's Mars rover zeroes in on August landing

ENERGY TECH
The pressure is on for aquanauts

Virgin Galactic Opens New Office

US scientists host 'bake sale for NASA'

XCOR Appoints Space Expedition Corp As General Sales Agent For Space Tourism Flights

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
Varied Views from the ISS

Strange Geometry - Yes, It's All About the Math

Capillarity in Space - Then and Now, 1962-2012

Dragon on board

ENERGY TECH
NuSTAR Arrives at Island Launch Site

Another Ariane 5 begins its initial build-up at the Spaceport

Boeing Receives DARPA Airborne Satellite Launch Study Contract

Sea Launch Delivers the Intelsat 19 Spacecraft into Orbit

ENERGY TECH
Tiny Planet-Finding Mirrors Borrow from Webb Telescope Playbook

Astronomers Probe 'Evaporating' Planet Around Nearby Star with Hobby-Eberly Telescope

Venus transit may boost hunt for other worlds

NSO To Use Venus Transit To Fine-Tune Search For Other Worlds

ENERGY TECH
New national supercomputer to perform astronomical feats

More people staying connected on vacation

Nano-engineered synthetic diamond sets a new quantum information record

Spin structure reveals key to new forms of digital storage




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