Shaolei Ren's Homepage

Shaolei Ren 

Shaolei Ren
Assistant Professor
School of Computing and Information Sciences
Florida International University


Recent Updates

  • New Paper “Greening Multi-Tenant Data Center Demand Response” will appear in the 33rd International Symposium on Computer Performance, Modeling, Measurements and Evaluation (IFIP WG7.3 Performance) 2015! [PDF]

    • Extended abstract appears at The Workshop on MAthematical performance Modeling and Analysis (MAMA) 2015. [PDF]

  • New Paper “Water-Constrained Geographic Load Balancing in Data Centers” will appear in IEEE Transactions on Cloud Computing (Special Issue on Green and Energy-Efficient Cloud Computing)!

  • New Paper “A Contract Design Approach for Colocation Data Center Demand Response” will appear in IEEE/ACM International Conference on Computer-Aided Design (ICCAD) 2015!

  • New Paper “Optimal Aggregation Policy for Reducing Tail Latency of Web Search” will appear in the 38th ACM SIG on Information Retrieval (SIGIR) 2015!

  • New Paper “Paying to Save: Reducing Cost of Colocation Data Center via Rewards” will appear in the 21st IEEE International Symposium on High Performance Computer Architecture (HPCA) 2015! [PDF] [Slides]

  • New Paper “A Truthful Incentive Mechanism for Emergency Demand Response in Colocation Data Centers” will appear in IEEE Conference on Computer Communications (INFOCOM), 2015. [PDF]

  • Two papers will appear in USENIX International Conference on Autonomic Computing (ICAC) 2014!

  • Article How Can Supercomputers Survive a Drought? appears at HPCwire



It's well-known that data centers are extremely power hungry. In the U.S., operators need to spend roughly 10 billion USD or more on their electricity bills each year. Admittedly, a handful of top-brand IT firms, e.g., Google, Facebook, Microsoft, and Apple, are doing great jobs in data center energy efficiency. But, they seem to have delivered to the public a “misleading” signal: data centers are already energy-efficient enough.

The existing efforts led by those Google-type IT giants as well as the research community have been primarily focused on those “hyper-scale data centers” (e.g., Google's data centers), which, however, are just a very small segment of the data center industry. I compiled the estimated percentage of electricity consumption by the U.S. data center segment in 2011 (shown above), excluding those small server closets and rooms, which claim themselves as “data centers” and actually take up nearly 50% of all the data center energy consumption.

My research focuses on power-management in multi-tenant colocation data centers and questions the wide perception “data centers are already energy-efficient” (delivered by Goolge-type IT giants). A few examples of colocation data centers are Equinix, Digital Realty, Verizon Terremark, CoreSite, etc. These data centers are “hidden” from the public and hence rarely investigated by the research community, but they constitute a much bigger segment of the data center industry than those so-called hyper-scale cloud data centers that have received a predominant amount of research attention. Further, compared to Google-type data centers, colocations, as well as a vast majority of enterprise/corporate data centers, are falling far behind in energy efficiency. More interestingly, multi-tenant colocation data centers present unique challenges that cannot be addressed by the existing solutions! For more details, please refer to the project page:

Research Overview

  • Power Management in Colocation Data Centers [PDF]

    Power-hungry data centers have been massively expanding in both number and scale, placing an increasing emphasis on optimizing data center power management. While the progress in data center energy efficiency is encouraging, the existing efforts have dominantly centered around owner-operated data centers (e.g., Google). Another unique and integral segment of data center industry  — - colocation data center, simply called “colocation”, which is the physical home to many Internet and cloud services – has not been well investigated, which, if still left unchecked, would become a major hurdle for sustainable growth of the digital economy.

    In sharp contrast with owner-operated data centers where operators have full control over both computing resources and facilities, colocation rents physical space to multiple tenants which individually control their own physical servers and power management, while the colocation operator is mainly responsible for facility support (e.g., providing reliable power and cooling). The uncoordinated power management, resulting from the colocation operator's lack of control over tenants’ servers, invalidates many of the existing power management solutions for owner-operated data centers, thereby making colocations’ operation highly inefficient.

  • Making Data Centers Less ‘‘Thirsty''

  • Others

  1. Performance-driven budget-constrained autoscaling

  2. Scheduling interactive services on heterogeneous processors

Short Bio

Shaolei Ren received the B.E. degree in Electronic Engineering from Tsinghua University in July 2006, the M.Phil. degree in Eletronic and Computer Engineering from Hong Kong University of Science and Technology in August 2008, and the Ph.D. degree in Electrical Engineering from University of California, Los Angeles, in June 2012. Since August 2012, he has been with Florida International University, where he currently holds a joint appointment of Assistant Professor in the School of Computing and Information Sciences and the Department of Electrical and Computer Engineering.

Dr. Ren directs the Sustainable Computing Group at FIU. His research centers around cloud computing and data center resource management, with an emphasis on sustainability. He received the Best Paper Award at the 8th International Workshop on Feedback Computing, the Best Paper Award at IEEE International Conference on Communications in 2009, and was selected by IBM T. J. Watson Research as one of the 10 Emerging Leaders in Multimedia and Signal Processing in 2010.


Shaolei Ren
School of Computing and Information Sciences
Florida International University
11200 SW 8th Street, ECS 350
Miami, FL 33199
United States

Phone: 305-348-2032
Fax: 305-348-3549