Y. Charlie Hu
Professor of Electrical and Computer Engineering
Professor of Computer Science (by courtesy)
University Faculty Scholar
School of ECE
Purdue University
(See also the official home page)
Address: Purdue University, School of ECE, EE Building, 465 Northwestern Ave., West Lafayette, Indiana 47907-2035
Phone: 765-494-9143
Fax : 765-494-3371
Email: ychu AaaaT purdue.edu
Secretary: Dee Dee Dexter, 494-3558

Links: Press, Awards, Google Scholar, Talks, Ph.D. Graduates, Publications (by topic  by date  by type)

Charlie's research interests are in mobile, distributed systems, operating systems, networking, and high performance computing. He leads the Distributed Systems and Networking Lab here at Purdue. He is a member of the Purdue Center for Wireless Systems and Applications (CWSA). Charlie co-founded the International Workshop on Mobile Peer-to-Peer Computing (MP2P) series in 2004. He received a Honda Initiation Grant Award in 2002, the NSF CAREER Award in 2003, and the 2009 Purdue University College of Engineering Early Career Research Award. Charlie was named an ACM Distinguished Scientist in 2010 and is a Senior Member of IEEE.

Charlie received the Ph.D. degree in Computer Science from Harvard University in 1997. Priori to joining Purdue in 2002, he was a research scientist in the Systems group in the Department of Computer Science at Rice University. Charlie was a visiting researcher at Microsoft Research Redmond in Fall 2008.

Selected Publications

Energy Profiling and Debugging in Smartphones:
Energy and Performance of Smartphone Radio Bundling in Outdoor Environments (WWW 2015)
On Death, Taxes, and Sleep Disorder Bugs in Smartphones (HotPower 2013)
How Much Energy Can We Save from Prefetching Ads? Energy Drain Analysis of Top 100 Apps (HotPower 2013)
Hypnos: Understanding and Treating Sleep Conflicts in Smartphones (Eurosys 2013)
Characterizing and Modeling the Impact of Wireless Signal Strength on Smartphone Battery Drain (Sigmetrics 2013)
Where is the energy spent inside my app? Fine Grained Energy Accounting on Smartphones with Eprof (EuroSys 2012, Best Student Paper Award) (264 cites in Google Scholar)
What is keeping my phone awake? Characterizing and Detecting No-Sleep Energy Bugs in Smartphone Apps (MobiSys 2012)
Fine-Grained Power Modeling for Smartphones Using System Call Tracing (EuroSys 2011)
Bootstrapping Energy Debugging on Smartphones: A First Look at Energy Bugs in Mobile Devices (HotNets 2011)

Data Center Networking:
Duet: Cloud Scale Load Balancing with Hardware and Software (SIGCOMM 2014)
On the impact of packet spraying in data center networks. (INFOCOM 2013)
The Only Constant is Change: Incorporating Time Varying Network Reservations in Data Centers (SIGCOMM 2012)
The TCP Outcast Problem: Exposing Unfairness in Data Center Networks (NSDI 2012)
On the Efficacy of Fine-Grained Traffic Splitting Protocols in Data Center Networks (Sigmetrics 2012 Ext. Abs.)
Latency Inflation with MPLS-based Traffic Engineering (IMC 2011)
Optimizing Cost and Performance in Online Service Provider Networks (NSDI 2010)

Operating Systems / Buffer Cache Management:
The Performance Impact of Kernel Prefetching on Buffer Cache Replacement Algorithms (SIGMETRICS 2005, IEEE TC 2007, Software Release) (84 cites in Google Scholar)
Program Counter Based Pattern Classification in Buffer Caching (OSDI 2004)
Program Counter Based Prediction Techniques for Dynamic Power Management (HPCA 2004, IEEE TC 2006)

Wireless Networking:
Pacifier: High-Throughput, Reliable Multicast without "Crying Babies" in Wireless Mesh Networks. (ToN 2012, Software Release)
CCACK: Efficient Network Coding Based Opportunistic Routing through Cumulative Coded Acknowledgments (ToN 2011)
Context Based Routing: Technique, Applications and Experience (NSDI 2008)
How to evaluate exotic wireless routing protocols? (HotNets 2008)
TDM MAC Protocol Design and Implementation for Wireless Mesh Networks (CoNEXT 2008)

How to Improve Your Google Ranking: Myths and Reality (WI 2010, press: InfoExec, JH Web, SpoonyLife, 1 of 7 favorite papers of Human Factors International 2014)
Botnet Spam Campaigns can be Long Lasting: Evidence, Implications, and Analysis (SIGMETRICS 2009)
iSPY: Detecting IP Prefix Hijacking on My Own (SIGCOMM 2008, ToN 2010)
Practical Defenses Against BGP Prefix Hijacking (CoNEXT 2007)
Practical Service Provisioning for Wireless Meshes (CoNEXT 2007)
Understanding Network Delay Changes Caused by Routing Events (SIGMETRICS 2007)
On the Impact of Research Network Based Testbeds on Wide-area Experiments (IMC 2006)

Exploiting the Synergy between Peer-to-Peer and Mobile Ad Hoc Networks (HotOS 2003)
Runtime Support for Distributed Sharing in Safe Languages (ACM TOCS 2003)



Recent Projects:

Software Releases


Research in our group has been supported by

Ph.D Students

Note to applicants

Past Postdoc

Ph.D and M.S. Graduates


ECE 469 Operating Systems Engineering (Spring 2015, 2014, 2013, 2011-2009, 2007-2005, 2003, 2002)
ECE 673 Distributed Computing Systems (Fall 2014, 2012, 2011, 2010, 2007-2002)
ECE Wireless Networking Seminar (Spring 2011)
ECE Wireless Networking Seminar (Fall 2010)

Professional activities


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