Raja R. Sambasivan

Computer Science Department, Tufts University.

Halligan Hall 211

161 College Ave

Medford, MA 02155

I am the Ankur & Mari Sahu Assistant Professor in the Computer Science Department at Tufts University. I mentor an incredible group of students at the D.O.C.C. Lab. Our work focuses on problem diagnosis techniques for distributed systems running in the cloud.

From November of 2016 to July of 2019, I was a Red Hat Visiting Research Scientist at BU. I worked on the Mass Open Cloud project with Orran Krieger, focusing on architectures for building vendor-neutral clouds and creating diagnosis tools for them. From May of 2013 to October of 2016, I was a postdoctoral researcher at CMU. I worked on the XIA project with Peter Steenkiste, focusing on evolvability for inter-domain routing protocols. Our SIGCOMM paper showed that two simple mechanisms implemented within routing protocols would allow them to facilitate the deployment of future inter-domain routing protocols.

I completed my Ph.D. at CMU in May 2013, advised by Greg Ganger. My dissertation, “Diagnosing performance changes in distributed systems by comparing request flows”, focused on creating distributed-tracing infrastructures and diagnosis tools that use them. The resulting papers (HotAC, NSDI, InfoVis, SoCC) influenced industrial tracing efforts, such as Jaeger’s trace comparisons, and have been cited over 350 times.

In my spare time, I enjoy playing tennis taking long walks, and exploring New England. I am “famous” for appearing in a PhDComics strip. In the strip, I ask CS PhD students to wear lab coats to work so that folks will know that we are researchers too :blush:. Don’t forget to pop on a pair of lab goggles when debugging!

research opportunities

Prospective PhDs: I recruit one to two PhD students per year to work to work on projects broadly related to systems and networking. I look for students who are curious, have strong technical skills, communicate well, and like exploring (slightly) crazy ideas. If you are interested, please apply to Tufts CS and send me an email. The application deadline is September 15th, 2021 for Spring 2022 admission and December 15th, 2021 for Fall 2022 admission.

Tufts undergrads & Master’s students: My lab hosts a few undergrads & Master’s students every year. If you are interested, send me an email. It helps if you have already taken or are planning to take Cloud Computing (CS 118) or Networking (CS 112).


Sep 9, 2021 Got an unexpected pick-me-up in my email this morning! I was nominated in Tufts’ 2021 senior survey as having had a “significant impact on a graduating senior’s intellectural and/or personal development.”
Aug 27, 2021 Our paper, “Automating choices for performance problems in distributed applications with VAIF,” was accepted to SoCC’21! Congrats to Mert Toslali and the rest of the team!
Jul 20, 2021 I’m serving on the PC for SOCC’21 and SIGMETRICS’22. Looking forward to reading some great papers! :sparkles:
Jun 1, 2021 Tomislav Zabcic-Mattric also joins the D.O.C.C. Lab as a Ph.D. student!
Feb 1, 2021 The D.O.C.C Lab is growing! Darby Huye joins as a Ph.D. student.

selected publications

  1. SoCC
    Automating instrumentation choices for performance problems in distributed applications with VAIF
    Toslali, Mert, Ates, Emre, Ellis, Alex, Zhang, Zhaoqi, Huye, Darby, Liu, Lan, Puterman, Samantha, Coskun, Ayse K., and Sambasivan, Raja R.
    In ACM Symposium on Cloud Computing 2021
    Bootstrapping evolvability for inter-domain routing with D-BGP
    Sambasivan, Raja R., Tran-Lam, David, Akella, Aditya, and Steenkiste, Peter
    In ACM Special Interest Group on Data Communication (SIGCOMM) 2017
  3. SoCC
    Principled workflow-centric tracing of distributed systems
    Sambasivan, Raja R., Shafer, Ilari, Mace, Jonathan, Sigelman, Benjamin H., Fonseca, Rodrigo, and Ganger, Gregory R.
    In ACM Symposium on Cloud Computing 2016
  4. NSDI
    Diagnosing performance changes by comparing request flows
    Sambasivan, Raja R, Zheng, Alice X, De Rosa, Michael, Krevat, Elie, Whitman, Spencer, Stroucken, Michael, Wang, William, Xu, Lianghong, and Ganger, Gregory R
    In USENIX Conference on Networked Systems Design and Implementation (NSDI) 2011