Share on Facebook Tweet on Twitter Share on LinkedIn Share by email
Our research
Content type
+
Downloads (455)
+
Events (487)
 
Groups (150)
+
News (2850)
 
People (716)
 
Projects (1161)
+
Publications (13025)
+
Videos (6121)
Labs
Research areas
Algorithms and theory47205 (376)
Communication and collaboration47188 (251)
Computational linguistics47189 (275)
Computational sciences47190 (247)
Computer systems and networking47191 (848)
Computer vision208594 (953)
Data mining and data management208595 (168)
Economics and computation47192 (129)
Education47193 (91)
Gaming47194 (85)
Graphics and multimedia47195 (265)
Hardware and devices47196 (243)
Health and well-being47197 (117)
Human-computer interaction47198 (1018)
Machine learning and intelligence47200 (1034)
Mobile computing208596 (89)
Quantum computing208597 (45)
Search, information retrieval, and knowledge management47199 (757)
Security and privacy47202 (372)
Social media208598 (93)
Social sciences47203 (319)
Software development, programming principles, tools, and languages47204 (688)
Speech recognition, synthesis, and dialog systems208599 (176)
Technology for emerging markets208600 (64)
1–25 of 848
Sort
Show 25 | 50 | 100
1234567Next 
Junchen Jiang, Rajdeep Das, Ganesh Ananthanarayanan, Philip A. Chou, Venkata Padmanabhan, Vyas Sekar, Esbjorn Dominique, Marcin Goliszewski, Dalibor Kukoleca, Renat Vafin, and Hui Zhang

The use of the public Internet for voice calls is here to stay. In spite of the volume and importance of Internet telephony, we have little understanding of (1) how network performance impacts user-perceived voice call quality, and (2) why and where such quality problems occur in the wild. To bridge this gap, we analyze a data set of 88 million calls from a large VoIP provider with clients spread across 1900 ASes and 126 countries. One of the key findings is that calls over bad networks are spread out...

Publication details
Date: 1 August 2016
Type: Inproceeding
Publisher: ACM – Association for Computing Machinery
Apurv Bhartia, Deeparnab Chakrabarty, Krishna Kant Chintalapudi, Lili Qiu, Bozidar Radunovic, and Ramachandran Ramjee

Interference in WiFi deployments is a growing problem
due to the increasing popularity of WiFi. Therefore it is important
that APs find the right channel to operate upon. Through a large
scale measurement study involving over 10,000 WiFi APs we show that
channel measurements and selection are most effective when
performed frequently (every few minutes). This is because of the
highly dynamic nature of WiFi traffic congestion.

Our key contribution in this paper is a...

Publication details
Date: 1 July 2016
Type: Inproceeding
Publisher: ACM – Association for Computing Machinery
Srikanth Kandula, Anil Shanbhag, Aleksandar Vitorovic, Matthaios Olma, Robert Grandl, Surajit Chaudhuri, and Bolin Ding

We present a system that approximates the answer to complex ad-hoc queries in big-data clusters by injecting samplers on-the-fly and without requiring pre-existing samples. Improvements can be substantial when big-data queries take multiple passes over data and when samplers execute early in the query plan. We present a new universe sampler which is able to sample multiple join inputs. By incorporating samplers natively into a cost-based query optimizer, we automatically generate plans with appropriate...

Publication details
Date: 1 June 2016
Type: Inproceeding
Publisher: ACM – Association for Computing Machinery
Hamed Esfahani, Jonas Fietz, Qi Ke, Alexei Kolomiets, Erica Lan, Erik Mavrinac, Wolfram Schulte, Newton Sanches, and Srikanth Kandula

Thousands of Microsoft engineers build and test hundreds of software products several times a day. It is essential that this continuous integration scales, guarantees short feedback cycles, and functions reliably with minimal human intervention. This paper describes CloudBuild, the build service infrastructure developed within Microsoft over the last few years. CloudBuild is responsible for all aspects of a continuous integration workflow, including builds, test and code analysis, as well as drops,...

Publication details
Date: 1 June 2016
Type: Inproceeding
Publisher: IEEE – Institute of Electrical and Electronics Engineers
Parisa Jalili Marandi, Christos Gkantsidis, Flavio Junqueira, and Dushyanth Narayanan
Publication details
Date: 1 May 2016
Type: Inproceeding
Jeff Rasley, Konstantinos Karanasos, Srikanth Kandula, Rodrigo Fonseca, Milan Vojnovic, and Sriram Rao
Publication details
Date: 1 May 2016
Type: Article
Publisher: USENIX
James Bornholt, Randolph Lopez, Douglas M. Carmean, Luis Ceze, Georg Seelig, and Karin Strauss

Demand for data storage is growing exponentially, but the capacity of existing storage media is not keeping up. Using DNA to archive data is an attractive possibility because it is extremely dense, with a raw limit of 1 exabyte per cubic millimeter, and long-lasting, with observed half-life of over 500 years.

This paper presents an architecture for a DNA-backed archival storage system. It is structured as a key-value store, and leverages common biochemical techniques to provide random access. We...

Publication details
Date: 1 April 2016
Type: Inproceeding
Publisher: ACM – Association for Computing Machinery
Jeff Rasley, Konstantinos Karanasos, Srikanth Kandula, Rodrigo Fonseca, Milan Vojnovic, and Sriram Rao

Job scheduling in Big Data clusters is crucial both for cluster operators’ return on investment and for overall user experience. In this context, we observe several anomalies in how modern cluster schedulers manage queues, and argue that maintaining queues of tasks at worker nodes has significant benefits. On one hand, centralized approaches do not use worker-side queues. Given the inherent feedback delays that these systems incur, they achieve suboptimal cluster utilization, particularly for workloads...

Publication details
Date: 1 April 2016
Type: Inproceeding
Andrew Newell, Gabriel Kliot, Ishai Menache, Aditya Gopalan, Soramichi Akiyama, and Mark Silberstein

Distributed actor systems are widely used for developing interactive scalable cloud services, such as social networks and on-line games. By modeling an application as a dynamic set of lightweight communicating “actors”, developers can easily build complex distributed applications, while the underlying runtime system deals with low-level complexities of a distributed environment.

We present ActOp — a data-driven, application-independent runtime mechanism for optimizing end-to-end service...

Publication details
Date: 1 April 2016
Type: Inproceeding
Publisher: ACM – Association for Computing Machinery
Qing Guo, Karin Strauss, Luis Ceze, and Rico Malvar

This paper proposes tailoring image encoding for an approximate storage substrate, developing an approximation-aware encoding algorithm. We develop a methodology to determine relative importance of encoded bits and store them in an approximate storage substrate that we tune to match their error tolerance. We present a case study with the progressive transform codec (PTC), a precursor to JPEG XR, and a phase-change memory (PCM) storage substrate that is optimized to minimize errors via biasing and tuned...

Publication details
Date: 1 April 2016
Type: Inproceeding
Publisher: ACM – Association for Computing Machinery
Publication details
Date: 1 April 2016
Type: Inproceeding
Sergey Legtchenko, Nicholas Chen, Daniel Cletheroe, Antony Rowstron, Hugh Williams, and Xiaohan Zhao

Rack-scale computers are dense clusters with hundreds of micro-servers per rack. Designed for data center workloads, they can have significant power, cost and performance benefits over current racks. The rack network can be distributed, with small packet switches embedded on each processor as part of a system-on-chip (SoC) design. Ingress/egress traffic is forwarded by SoCs that have direct uplinks to the data center. Such fabrics are not fully provisioned and the chosen topology and uplink placement...

Publication details
Date: 16 March 2016
Type: Inproceeding
Publisher: USENIX Association
Yang Li, Di Wang, Saugata Ghose, Jie Liu, Sriram Govindan, Sean James, Eric Peterson, John Siegler, Rachata Ausavarungnirun, and Onur Mutlu

Fuel cells are a promising power source for future data centers, offering high energy efficiency, low greenhouse gas emissions, and high reliability. However, due to mechanical limitations related to fuel delivery, fuel cells are slow to adjust to sudden increases in data center power demands, which can result in temporary power shortfalls. To mitigate the impact of power shortfalls, prior work has proposed to either perform power capping by throttling the servers, or by leveraging energy storage...

Publication details
Date: 12 March 2016
Type: Proceedings
Publisher: the 22nd IEEE Symposium on High-Performance Computer Architecture (HPCA)
Trinabh Gupta, Natacha Crooks, Whitney Mulhern, Srinath Setty, Lorenzo Alvisi, and Michael Walfish
Publication details
Date: 1 March 2016
Type: Inproceeding
Publisher: USENIX – Advanced Computing Systems Association
Jeff Rasley, Konstantinos Karanasos, Srikanth Kandula, Rodrigo Fonseca, Milan Vojnovic, and Sriram Rao

Job scheduling in Big Data clusters is crucial both for cluster operators’ return on investment and for overall user experience. In this context, we observe several anomalies in how modern cluster schedulers manage queues, and argue that maintaining queues of tasks at worker nodes has significant benefits. On one hand, centralized approaches do not use worker-side queues. Given the inherent feedback delays that these systems incur, they achieve suboptimal cluster utilization, particularly for workloads...

Publication details
Date: 1 March 2016
Type: Technical report
Number: MSR-TR-2016-12
Hongqiang Harry Liu, Raajay Viswanathan, Matt Calder, Aditya Akella, Ratul Mahajan, Jitendra Padhye, and Ming Zhang

We present Footprint, a system for delivering online services in the “integrated” setting, where the same provider operates multiple elements of the infrastructure (e.g., proxies, data centers, and the wide area network). Such integration can boost system efficiency and performance by finely modulating how traffic enters and traverses the infrastructure. But fully realizing its benefits requires managing complex dynamics of service workloads. For instance, when a group of users are directed to a new...

Publication details
Date: 1 March 2016
Type: Inproceeding
Publisher: USENIX – Advanced Computing Systems Association
Sergey Legtchenko, Xiaozhou Li, Antony Rowstron, Austin Donnelly, and Richard Black

Cloud providers and companies running large-scale data centers offer near-line, cold, and archival data storage, which trade access latency and throughput performance for cost. These often require physical rack-scale storage designs, e.g. Facebook/Open Compute Project (OCP) Cold Storage or Pelican, which co-design the hardware, mechanics, power, cooling and software to minimize costs to support the desired workload. A consequence is that the rack resources are restricted, requiring a software stack that...

Publication details
Date: 22 February 2016
Type: Inproceeding
Publisher: USENIX Association
Robert Grandl, Srikanth Kandula, Sriram Rao, Aditya Akella, and Janardhan Kulkarni

We present a scheduler that improves cluster utilization and job completion times by packing tasks having multi-resource requirements and inter-dependencies. While the problem is algorithmically very hard, we achieve near-optimality on the job DAGs that appear in production clusters at a large enterprise and in benchmarks such as TPC-DS. A key insight is that carefully handling the long-running tasks and those with tough-to-pack resource needs will produce good-enough schedules. However, which subset of...

Publication details
Date: 2 February 2016
Type: Technical report
Publisher: Microsoft Research
Number: MSR-TR-2016-19
Vasileios Karakostas, Jayneel Gandhi, Adrián Cristal, Mark D. Hill, Kathryn S. McKinley, Mario Nemirovsky, Michael M. Swift, and Osman S. Unsal

Address translation is fundamental to processor performance. Prior work focused on reducing Translation Lookaside Buffer (TLB) misses to improve performance and energy, whereas we show that even TLB hits consume a significant amount of dynamic energy.

To reduce the energy cost of address translation, we first propose Lite, a mechanism that monitors the performance and utility of L1 TLBs, and adaptively changes their sizes with way-disabling. The resulting TLBLite organization...

Publication details
Date: 1 February 2016
Type: Article
Publisher: IEEE – Institute of Electrical and Electronics Engineers
Ivan Jibaja, Ting Cao, Stephen M. Blackburn, and Kathryn S. McKinley

Static and dynamic power constraints are steering chip manufacturers to build single-ISA Asymmetric Multicore Processors (AMPs) with big and small cores. To deliver on their energy efficiency potential, schedulers must consider core sensitivity, load balance, and the critical path. Applying these criteria effectively is challenging especially for complex and non-scalable multithreaded applications. We demonstrate that runtimes for managed languages, which are now ubiquitous, provide a unique opportunity...

Publication details
Date: 1 February 2016
Type: Article
Publisher: ACM – Association for Computing Machinery
Jing Li, Kunal Agrawal, Sameh Elnikety, Yuxiong He, I-Ting Angelina Lee, Chenyang Lu, and Kathryn S. McKinley

Interactive web services increasingly drive critical business workloads such as search, advertising, games, shopping, and finance. Whereas optimizing parallel programs and distributed server systems have historically focused on average latency and throughput, the primary metric for interactive applications is instead consistent responsiveness, i.e., minimizing the number of requests that miss a target latency. This paper is the first to show how to generalize work-stealing, which is traditionally used...

Publication details
Date: 1 February 2016
Type: Article
Publisher: ACM – Association for Computing Machinery
Ian A. Kash and Peter B. Key
Publication details
Date: 1 December 2015
Type: Article
Publisher: IEEE – Institute of Electrical and Electronics Engineers
Nimantha Baranasuriya, Vishnu Navda, Venkata N. Padmanabhan, and Seth Gilbert

Mobile communication is often frustratingly slow. When a user encounters poor performance, and perhaps even “confirms” the same by running a speed test, the tendency is to ascribe blame to the user’s last-mile provider. However, as we argue in this paper, a more nuanced approach is needed to identify the location of the bottleneck responsible for the poor performance. Specifically, we focus on the question of whether the bottleneck lies in the cellular last hop (3G or LTE link) or elsewhere in the WAN...

Publication details
Date: 1 December 2015
Type: Proceedings
Publisher: ACM – Association for Computing Machinery
Dan Alistarh, Jennifer Iglesias, and Milan Vojnovic

In many applications, the structure of data can be represented by a hyper-graph, where the data items are vertices, and the associations among items are represented by hyper-edges. Equivalently, we are given as input a bipartite graph with two kinds of vertices: items, and associations (which we refer to as topics). We consider the problem of partitioning the set of items into a given number of partitions, such that the maximum number of topics covered by a partition is minimized.

This is a...

Publication details
Date: 1 December 2015
Type: Inproceeding
Rajat Kateja, Nimantha Baranasuriya, Vishnu Navda, and Venkata N. Padmanabhan

Real-time, interactive streaming for applications such as audio-video conferencing (e.g., Skype) and cloud-based gaming depends critically on the network providing low latency, jitter, and packet loss, much more so than on-demand streaming (e.g., YouTube) does. However, WiFi networks pose a challenge; our analysis of data from a large VoIP provider and from our own measurements shows that the WiFi access link is a significant cause of poor streaming experience.

To improve streaming quality over...

Publication details
Date: 1 December 2015
Type: Proceedings
Publisher: ACM – Association for Computing Machinery
1–25 of 848
Sort
Show 25 | 50 | 100
1234567Next 
> Our research