Now showing items 126-145 of 245

    • Maestro: A System for Scalable OpenFlow Control 

      Cai, Zheng; Cox, Alan L.; Ng, T. S. Eugene (2010-12-04)
      The fundamental feature of an OpenFlow network is that the controller is responsible for the initial establishment of every flow by contacting related switches. Thus the performance of the controller could be a bottleneck. This paper shows how this fundamental problem is addressed by parallelism. The state of the art OpenFlow controller, called NOX, ...
    • Maestro: Balancing Fairness, Latency and Throughput in the OpenFlow Control Plane 

      Cai, Zheng; Cox, Alan L.; Ng, T. S. Eugene (2011-12-20)
      The fundamental feature of an OpenFlow network is that the controller is responsible for the configuration of switches for every traffic flow. This feature brings programmability and flexibility, but also puts the controller in a critical role in the performance of an OpenFlow network. To fairly service requests from different switches, to achieve ...
    • Managing Interprocedural Optimization 

      Hall, Mary Wolcott (1998-04-28)
      This dissertation addresses a number of important issues related to interprocedural optimization. Interprocedural optimization is an integral component in a compilation system for high-performance computing. The importance of interprocedural optimization stems from two sources: it increases the context available to the optimizing compiler, and it ...
    • Manetho: Fault Tolerance in Distributed Systems Using Rollback-Recovery and Process Replication 

      Elnozahy, Elmootazbellah (1993-10)
      This dissertation presents a new protocol that allows rollback-recovery and process replication to co-exist in a distributed system. The protocol relies on a novel data structure called the antecedence graph, which tracks the nondeterministic events during failure-free operation and provides information for recreating them if a failure occurs. The ...
    • Mapping HPF onto the Grid 

      Mandal, Anirban (2003-03-12)
      For this thesis, we have developed a tool for mapping HPF applications onto the Grid using the GrADS infrastructure. To build the mapper, the tool makes use of SPMD task graph representation of the application. Using the mapper generated, we have been able to launch an HPF application, namely tomcatv, on the Grid. To our knowledge this is the only ...
    • Mathematical Properties of Variational Subdivision Schemes 

      Warren, Joe (1998-09-24)
      Subdivision schemes for variational splines were introduced in a previous paper. This technical report focuses on discussing the mathematical properties of these subdivision schemes in more detail. Please read the original paper before reading this analysis.
    • Matrix Transposition on a Mesh with Blocking Transmissions 

      Hofri, Micha; Thomson, David L. (1997-02-07)
      A time-optimal procedure to transpose in situ a matrix stored over a distributed memory 2-dimensional mesh-connected parallel computer is shown. The matrix need not be square. Only nearest-neighbor blocking communications is used, and a small bounded buffer space is required.
    • Measurement-Based Analysis, Modeling, and Synthesis of the Internet Delay Space for Large Scale Simulation 

      Zhang, Bo; Ng, T. S. Eugene; Nandi, Animesh; Riedi, Rudolf H.; Druschel, Peter; (2006-10-04)
      The characteristics of packet delays among edge networks in the Internet can have a significant impact on the performance and scalability of global-scale distributed systems. Designers rely on simulation to study design alternatives for such systems at scale, which requires an appropriate model of the Internet delay space. The model must preserve the ...
    • Memento: A Collaborative, Semantic-Based Infrastructure for Building Assistants 

      Baker, Donald (1998-03-02)
      Memento is a software infrastructure to support the construction and evolution of assistant applications (or assistants) that act as adjuncts to the human mind. Each assistant embodies an effective understanding of some information domain or problem domain. The assistant employs this understanding to aid a user or user community in the manipulation, ...
    • Memory-Hierarchy Management 

      Carr, Steve (1992-09)
      The trend in high-performance microprocessor design is toward increasing computational power on the chip. Microprocessors can now process dramatically more data per machine cycle than previous models. Unfortunately, memory speeds have not kept pace.The result is an imbalance between computation speed and memory speed. This imbalance is leading machine ...
    • Mitosis: A High Performance, Scalable Virtual Memory System 

      Cox, Alan; Navarro, Juan (2001-05-08)
      Many modern applications use virtual memory APIs introduced in the 1980's in unforeseen ways, stressing the underlying data structures and exposing the old designs to a variety of performance and scalability problems. The two-decade-old data structures show their age when, for instance, a Web server maps thousands of files or a garbage collector plays ...
    • Mixing Indexed Types and Hindley-Milner Type Inference 

      Pašalić, Emir; Siek, Jeremy G.; Taha, Walid (2006-07-28)
      This paper addresses the question of how to extend OCaml’s Hindley-Milner type system with types indexed by logical propositions and proofs of the Coq theorem prover, thereby providing an expressive and extensible mechanism for ensuring fine-grained program invariants. We propose adopting the approached used by Shao et al. for certified binaries. ...
    • MMS: An Autonomic Network-Layer Foundation for Network Management 

      Gogineni, Hemant; Greenberg, Albert; Maltz, David A.; Ng, T. S. Eugene; Yan, Hong; (2008-12-03)
      Networks cannot be managed without communication among geographically distributed network devices and control agents. Unfortunately, computer networks today lack an autonomic mechanism that enables such communications, and the stopgap solutions used in practice are seriously flawed. To address the problem, this paper presents the design and implementation ...
    • Modeling 3D Minimal-Energy Curves of Given Length 

      Kavraki, Lydia E.; Moll, Mark (2005-01-04)
      We present a subdivision scheme for the construction of 3D minimal-energy curves of given length that satisfy endpoint constraints. When given desired positions and tangents for the endpoints, and the length of the curve, the scheme iteratively builds up a minimal-energy curve. During each iteration the algorithm solves a low-dimensional optimization ...
    • Models of Control and Their Implications for Programming Language Design 

      Sitaram, Dorai (1994-04)
      This work uses denotational models to understand and improve the part of a programming language concerned with non-local control operators. These operators let the programmer identify and restore arbitrary control contexts in the program execution path, and thus form a powerful component of many modern programming languages. We use a variety of ...
    • Module Checking 

      Kupferman, Orna; Vardi, Moshe Y.; Wolper, Pierre (1998-02-22)
      In computer system design, we distinguish between closed and open systems. A closed system is a system whose behavior is completely determined by the state of the system. An open system is a system that interacts with its environment and whose behavior depends on this interaction. The ability of temporal logics to describe an ongoing interaction of ...
    • Motion Planning for Knot Untangling 

      Ladd, Andrew M.; Kavraki, Lydia E. (2004-01-01)
      When given a very tangled but unknotted circular piece of string it is usually quite easy to move it around and tug on parts of it until it untangles. However, solving this problem by computer, either exactly or heuristically, is challenging. Various approaches have been tried, employing ideas from algebra, geometry, topology and optimization. This ...
    • Multi-stage Programming for Mainstream Languages 

      Abdelatif, Tamer; Inoue, Jun; Ricken, Mathias; Taha, Walid; Westbrook, Edwin; (2009-07-27)
      Multi-stage programming (MSP) provides a disciplined approach to run-time code generation. In the purely functional setting, it has been shown how MSP can be used to reduce the overhead of abstractions, allowing clean, maintainable code without paying performance penalties. Unfortunately, MSP is difficult to combine with imperative features, which ...
    • Multiplication by Integer Constants 

      Briggs, Preston; Harvey, Timothy J. (2003-10-21)
      Some modern machines have no integer multiple instruction and must rely on expensive software methods to compute integer products. In other cases, the multiply instruction is significantly slower than simple integer addition. When faced with computing n*c, where n is some unknown integer value and c is a known integer constant, we can avoid the need ...
    • Network Stack Architecture for Future Sensors 

      Johnson, David B.; Kumar, Rajnish; PalChaudhuri, Santashil; Ramachandran, Umakishore (2005-01-26)
      With wireless ad hoc sensor networks, there is simultaneously a need and an opportunity to optimize the protocol stack behavior to match the sensor-based applications. A general-purpose internet stack is neither appropriate nor sufficient to meet the needs of such applications. Motivated by this observation, we pose two related questions: (a) What ...