Graduate Student Profile: Marisabel Guevara

From the Summer 2013 issue of Threads

Marisabel Guevara (2nd from left) with students Qiuyun Wang, Sam Xi, and Nazia Tabassum

In male-dominated fields like engineering and computer science, young women sometimes struggle to find mentors they can identify with and model their careers after. That was not the case with Duke graduate student Marisabel Guevara, whose father was an electrical engineer in her home country of Bolivia. Guevara and her father made a hobby out of various electrical engineering projects, and even installed the electrical wiring in their new home together when she was twelve years old.

“The fact that I was working with my dad, I never felt like engineering was something I couldnít do,” recalls Guevara. “At school, that path wasnít presented as an option. But my experiences at home made me realize it was possible.”

Though she began with an interest in electrical engineering, Guevara quickly gravitated toward computer engineering and went to the University of Arkansas in 2004 to pursue an undergraduate degree in the discipline. There she was exposed to high performance computing, the use of supercomputers and computer clusters to run massive simulations. Guevara started to think about how to redesign computers to maximize their performance and maintain their energy efficiency, and went on to graduate school in computer architecture at the University of Virginia.

While working on her masterís degree, Guevara met a female professor Ė the only woman specializing in computer architecture in her department Ė and began to entertain the notion of becoming a professor herself one day. Though the professor didnít become her formal advisor, she served as a role model for Guevara and met with her informally to share interesting pieces of literature or convey career advice.

“Having female professors encourages female students to consider getting a PhD, because if you donít see that it might be harder to make the connection in your mind,” explained Guevara. “I saw that my mentor was able to manage her personal life and professional life very well. Plus it seemed like this was an exciting job to be able to do for the rest of your life.”

In 2010 Guevara came to Duke to begin her dissertation work studying new ways to design and manage energy-efficient datacenters, the large distributed centers that underpin cloud computing. Instead of building datacenters with all high-power components such as processors or memory, Guevara is looking at incorporating low-power parts like those found in cell phones and tablets. Her key contribution has been to formulate management of these datacenters as an economic market, where applications like web search, email, and iTunes are all bidding for resources. By attaching a market value to the resources needed, Guevara is able to build a scheduler or resource allocator that is optimized for performance and energy efficiency. Her research has been presented at Google and more recently at the High Performance Computer Architecture Conference, one of the fieldís premier venues.

Even though such presentations and publications are often how oneís success is measured, Guevara has chosen to make time to help students learn how to do their own research. She has mentored six undergraduates and a number of incoming graduate students, and received the 2013 Deanís Award for Excellence in Mentoring for her efforts. In his nomination letter, Guevaraís advisor Benjamin Lee wrote that she recognizes each studentís natural talents and acquired skills, identifying a clearly defined sub-problem in her research to which those talents and skills can be applied. By linking talent to real research questions, Lee explained, Guevara fosters a sense of accomplishment in the students she mentors.

“There is fine balance between how much time you can spend on mentoring versus on your own work,” said Guevara. “I think that is why my mentoring has been very research-oriented. In all of the projects I have worked on with students there have been questions that came up during my own research that I would not have a chance to answer on my own. I just help them see the research question and come up with their own solution to the problem.”

For example, last summer Guevara mentored Emily Bragg, a Georgia Tech student who came to Duke as part of the National Science Foundationís Research Experience for Undergraduates program. Bragg was interested in web search engines, so Guevara suggested that they conduct web search simulations to define what kind of requests demanded high performance, server processors versus those that could be satisfied with the more efficient but lower-performing, mobile processors. The research will be published in a high profile journal and has inspired yet another bright young mind to pursue a career in computer science.

“The entire experience changed my opinion from a slight inclination towards grad school and research towards being set on that; I know that I can ask Marisabel anything about that process as well and get advice along the way,” said Bragg.

Guevara says she is happy to give advice, because that type of support and encouragement has gotten her to where she is today. When she traveled to China last month to present her most recent research findings, her mom and dad were there to cheer her on. Ironically, her dadís own electrical engineering work has taken him into the realm of datacenters, so Guevara now finds herself advising him on how best to set up the servers and clouds.

“I think the best advice I can give is to not be afraid to ask questions or to push yourself to find the answers,Ē shared Guevara. “And never underestimate yourself.”

Return to Profiles main page