Y. Charlie Hu is a Professor of Electrical and Computer
Engineering and Computer Science (by courtesy) and a University
Faculty Scholar at Purdue University. He received Ph.D. in Computer
Science from Harvard in 1997, and was a postdoc at Rice
University working with Willy Zwaenepoel, Peter Druschel, Alan Cox,
and a co-founder of the iMimic Networking, Inc. before
joining Purdue in 2002. Charlie received the NSF CAREER Award in 2003,
the 2009 Early Career Research Award from Purdue College of
Engineering, and was named an ACM Distinguished Member in 2010. His
research interests lie broadly in distributed systems, operating
systems, computer networking, wireless networking, and high
performance computing.

AG 1, SWS, RG1, MMCI   Info

Expert Audience

English

60 Minutes

Saarbrücken

Despite the incredible market penetration of smartphones and
exponential growth of the app market, utility of smartphones has been
and will remain severely limited by the battery life. As such, energy
has increasingly become the scarcest resource on smartphones that
critically affects user experience. In this talk, I will start with a
first study that characterizes smartphone energy bugs, or ebugs,
broadly defined as errors in the system (apps, OS, hardware, firmware,
or external conditions) that result in unexpected smartphone battery
drainage and leads to significant user frustrations.

As a first step towards taming ebugs, we built the first fine-grained
energy profiler, eprof, that performs energy accounting and hence
answers the very question "where was the energy spent in the app?" at
the per-routine, per-thread, and per-process granularity. Building
eprof in turn requires a fine-grained, online power model which we
have developed that captures the unique asynchronous power behavior of
modern smartphones. Using eprof, we dissected the energy drain of some
of the most popular apps in Android Market and discovered ebugs in
popular apps like Facebook.

While essential, eprof only provides a semi-automatic tool for energy
debugging. The "holy grail" in energy debugging in smartphones is to
develop fully automatic debugging techniques and tools, which can draw
synergies from many areas of computer science including OS, PL,
compilers, machine learning, HCI, etc. I will present the first
automatic ebug detection technique based on static compiler analysis for
detecting "no-sleep" energy bugs, the most notorious category of
energy bugs found in smartphone apps.

Brigitta Hansen

0681 93039102

--email hidden

Yes

Kaiserslautern

G26

206

passcode not visible

logged in users only