Warehouse-scale Computers: Opportunities and Challenges

Tuesday, December 03, 2013
6:00 PM
NHB 1.720
Free and open to the public

Web-service companies such as Google, Microsoft, Amazon, Yahoo, and Apple spend hundreds of millions of dollars to construct and operate Warehouse-scale Computers (WSC) which provide popular web-services such as search, social networking, webmail, video streaming, enterprise management tools, online maps, automatic translation, and online courses. The primary advantages of WSC are the scalability and cost benefits for both the end-users and web-service companies. These WSCs house hundreds to thousands of machines to provide the computing resources needed to serve millions of users. To limit the cost of ownership of WSCs, these machines are composed of commodity components which are cheap and easily replaceable, often multi-cores. When multiple applications are running simultaneously on a multi-core machine, resources sharing and contention among cores can result in a significant amount of performance interference. This interference leads to a significant problem in meeting the requirements of user facing web-service applications. To avoid the constant unpredictable threat that shared resource contention poses to an application’s QoS, datacenter operators typically disallow co-locations of latency-sensitive jobs with other jobs. This over-provisioning of computer resources reduces the overall utilization of WSCs and results in an unnecessarily high cost and a large environmental footprint for a given set of web-service workloads. In this talk, I discuss these issues and present our research using scheduling and compiling to improve the capability and cost effectiveness by improving resource efficiency. Specifically, we reconcile the apparent conflict between the need to maintain high QoS for latency-critical, high-priority services and the desire to increase hardware utilization by scheduling multiple workloads per server.

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Mary Lou Soffa

Mary Lou Soffa

Owens R. Cheatham Professor
The University of Virginia

Mary Lou Soffa is the Owen R. Cheatham Professor of Sciences at the Computer Science Department at the University of Virginia. From 2004 to 2012, she served as the Department Chair at UVA.  From 1977 to 2004, she was a Professor of Computer Science at the University of Pittsburgh and also served as the Dean of Graduate Studies in the College of Arts and Sciences from 1991 to 1996. Her research interests include optimizing compilers, virtual execution environments, software testing, program analysis, software security,  and software systems for multi-core architectures.  She has published over 150 articles and  has directed 30 Ph.D. students to completion, half of whom are women.   Mary Lou received the Ken Kennedy Award in 2012 for contributions to compiler technology and software engineering, exemplary service to the profession, and lifelong dedication to mentoring and improving diversity in computing.  Mary Lou is both  an IEEE Fellow and  an ACM Fellow. She  received the Anita Borg Technical Leadership Award in 2011 and was selected for the Presidential Award for Excellence in Science, Mathematics and Engineering Mentoring the same year. She received the Computing Research Association (CRA) Nico Habermann Award in 2006  and was selected as a Girl Scout Woman of Distinction in 2003 . She has received both the SIGPLAN and SIGSOFT Service Awards.  She has served as conference chair, program chair or program committee member for  numerous conferences.  She currently serves on the ACM Publication Board and was elected in 2008 and 2012 to serve on the ACM Council.  She also serves on the CRA-W Board.