Vasanth Venkatachalam






School of Information and Computer Science
University of California, Irvine
Irvine, CA 92697-3430
Email: vasanthv6@gmail.com
Private Voicemail: 949-468-5640




Hello and welcome to my webpage. I have graduated from the School of Information and Computer Science at the University of California, Irvine . My doctoral advisor was Professor Michael Franz.

I have developed a new approach to controlling the speed setting of a processor while programs are executing, in a way that saves energy and minimizes runtime overhead. My prototype implementations of this approach in Sun's Java Virtual Machine and Intel's Pin Dynamic Optimization Tool save up to 26% of the total system energy consumption on a typical laptop, with a runtime overhead of less than 2%. You can read more about this in my completed dissertation . To see a condensed version of this, have a look at my presentation slides.

During my fourth year of graduate school, I wrote the first survey paper on power-aware computing to be published in ACM Computing Surveys.

Below is a brief overview of my background. You can find more details in the links mentioned above.

Brief CV

Education

  • Ph.D. in Information and Computer Science, University of California, Irvine, May 2007.
  • MS in Information and Computer Science, University of California, Irvine, 2002.
  • Bachelors in Mathematics and Philosophy, Wesleyan University, 1998. (High Honors in Philosophy.)

Research Experience

Graduate Student Researcher. University of California, Irvine, 2003-present.

As part of my PhD research, I have developed a new way of predicting a workload's execution time based on minute variations of processor clock speed. My approach can predict a workload's execution time at any clock frequency by adjusting the processor speed by just a single step at runtime and extrapolating from the difference in execution cycles. On a typical laptop, it has an accuracy of above 90% for a majority of workloads from standard benchmark suites.

Moreover, using simulations, I discovered that the step interval, or distance between consecutive clock frequencies, can be considerably smaller than the hundreds of megahertz offered by typical laptops that support dynamic frequency scaling. In fact, by adjusting the processor speed in the simulator by as little as tens of megahertz, my approach is able to predict what the execution times would be if the speed were adjusted by hundreds of megahertz.

Using these results, I have implemented a lightweight algorithm for dynamic processor clock frequency control. While a workload is running, it slows the processor down just a little, to the next step, and uses the information from these two points (the current and next step) to quickly assess how compute-bound the workload is and assign it the optimal clock frequency. The prototypes that I have developed in Sun's Java Virtual Machine and Intel's Pin tool save up to 26% of the total system energy on a typical laptop with less than 2% runtime overhead.

Graduate Student Researcher, University of California, Irvine, 2002-2003

Traditionally, the infrastructure for executing mobile programs resides entirely on the devices on which these programs run. Thus these devices, many of which are resource constrained, bear the costly burden of doing all the work involved in compiling and executing these programs, and storing the entire infrastructure needed to do so.

I developed the compiler and runtime infrastructure for the first working prototype of Proxy Virtual Machine, a system that allows expensive operations in mobile code deployment, such as compilation, verification and optimization, to be shifted away from their resource constrained targets and executed on a more powerful "always-on" server infrastructure (the Proxy).

Honors and Awards

  • GAANN Fellowship, Department of Information and Computer Science, University of California, Irvine, August 2000 - June 2006. (Includes a full tuition waver and generous cash stipend.)
  • Allan Ross Anderson Fellowship, Department of Philosophy, University of Pittsburgh, Fall 1999.
  • Andrew Mellon Fellowship, Department of Philosophy, University of Pittsburgh, Fall 1998.
  • Summa Cum Laude (High Honors), Wesleyan University, May 1998.
  • Accepted to Phi Beta Kappa Academic Honor Society, Wesleyan University, May 1998.
  • Rice Prize for Excellent Mathematics Student in Graduating Class, Wesleyan University, 1998.

Publications

Technical Reports

  • Self-Calibrating Processor Speed: A New Feedback Loop For Dynamic Voltage Scaling Control; Vasanth Venkatachalam, Christian Probst and Michael Franz; Technical Report No. 06-15, School of Information and Computer Science, University of California, Irvine, December 2006.
    (Download paper -- .pdf)
  • ProxyVM: A Network-based Compilation Infrastructure for Resource-Constrained Devices; Technical Report No. 03-13, School of Information and Computer Science, University of California, Irvine, March 2003.
    (Download paper -- .pdf)
  • Virtual Machine Driven Dynamic Voltage Scaling; Vivek Haldar, Christian Probst, Vasanth Venkatachalam, and Michael Franz; Technical Report No. 03-21, School of Information and Computer Science, University of California, Irvine; October 2003.
    (Download paper -- .pdf)

Presentations

  • Self-Calibrating Processors: A New Feedback Loop for Dynamic Voltage Scaling Control, Dagstuhl Seminar on Power Aware Computing Systems, Schloss Dagstuhl, Germany, January 2007.
  • Continuous Compiler Driven Dynamic Voltage Scaling, Dagstuhl Seminar on Power Aware Computing Systems, Schloss Dagstuhl, Germany, April 2005.
  • The Proxy Virtual Machine: Code Generation in the Network and Why It Is Superior, Office of Naval Research Program Review, Annapolis, MD, May 2004.

Personal

  • US Citizen.

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