Now showing items 71-90 of 245

    • Dagster: Censorship-Resistant Publishing Without Replication 

      Stubblefield, Adam; Wallach, Dan S. (2002-07-23)
      In this paper we present Dagster, a new censorship-resistant publishing scheme. Unlike previous censorship-resistant schemes, Dagster does not rely on the widespread replication of data and can even be used in a single server setting. It accomplishes this by ``intertwining'' legitimate and illegitimate data, so that a censor can not remove objectionable ...
    • Data-Parallel Compiler Support for Multipartitioning 

      Chavarria, Daniel (2001-03-23)
      Strategies for partitioning an application's data determine both the range of suitable parallelizations and their potential efficiency. For multi-directional line-sweep computations, multipartitioned data distributions offer better parallel efficiency and scalability than block unipartitionings. This paper describes extensions to the Rice dHPF compiler ...
    • Decomposition-based Motion Planning: Towards Real-time Planning forRobots with Many Degrees of Freedom 

      Brock, Oliver; Kavraki, Lydia E. (2000-08-25)
      Research in motion planning has been striving to develop faster and faster planning algorithms in order to be able to address a wider range of applications. In this paper a novel real-time motion planning framework, called decomposition-based motion planning, is proposed. It is particularly well suited for planning problems that arise in service and ...
    • Denial of Service via Algorithmic Complexity Attacks 

      Crosby, Scott A.; Wallach, Dan S. (2003-02-12)
      We present a new class of low-bandwidth denial of service attacks that exploit algorithmic deficiencies in many common applications' data structures. Frequently used data structures have "average-case'' expected running time that's far more efficient than the worst case. For example, both binary trees and hash tables can degenerate to linked lists ...
    • Design and Performance of PRAN: A System for Physical Implementation ofAd Hoc Network Routing Protocols 

      Du, Shu; Johnson, David B.; PalChaudhuri, Santashil; Saha, Amit Kumar; To, Khoa (2005-02-28)
      Simulation and physical implementation are both valuable tools in evaluating ad hoc network routing protocols, but neither alone is sufficient. In this paper, we present the design and performance of PRAN, a new system for implementation of ad hoc network routing protocols that merges these two types of evaluation tools. PRAN (Physical Realization ...
    • Differentiated and Predictable Quality of Service in Web Server Systems 

      Aron, Mohit (2000-10-31)
      As the World Wide Web experiences increasing commercial and mission-critical use, server systems are expected to deliver high and predictable performance. The phenomenal improvement in microprocessor speeds, coupled with the deployment of clusters of commodity workstations has enabled server systems to meet the continually increasing performance ...
    • Domain-Specific Type Inference for Library Generation in a Telescoping Compiler 

      Chauhan, Arun; Kennedy, Ken; McCosh, Cheryl (2004-04-14)
      Telescoping languages is a strategy for allowing users to develop code in high-level, domain-specific languages and still achieve high performance. It uses extensive offline processing of the library defining the language. This process speculatively determines the possible uses of the library subroutines and generates variants specialized toward those ...
    • Dynamic Multiple Pattern Matching 

      Idury, Ramana (1994-05)
      Pattern matching algorithms are among the most important and practical contributions of theoretical computer science. Pattern matching is used in a wide variety of applications such as text editing, information retrieval, DNA sequencing, and computer vision. Several combinatorial problems arise in pattern matching such as matching in the presence of ...
    • E-FRP With Priorities 

      Inoue, Jun; Kaiabachev, Roumen; Taha, Walid; Zhu, Angela (2009-07-15)
      E-FRP is declarative language for programming resource-bounded, event-driven systems. Its original high-level semantics requires that each event handler execute atomically. This facilitates reasoning about E-FRP programs, and therefore is a desirable feature of the language. However, the original compilation strategy requires that each handler complete ...
    • Effective Communication Coalescing for Data-Parallel Applications 

      Chavarria-Miranda, Daniel; Mellor-Crummey, John (2005-07-29)
      Communication coalescing is a static optimization that can reduce both communication frequency and redundant data transfer in compiler-generated code for regular, data parallel applications. We present an algorithm for coalescing communication that arises when generating code for regular, data-parallel applications written in High-Performance Fortran ...
    • Effective Performance Measurement and Analysis of Multithreaded Applications 

      Mellor-Crummey, John; Tallent, Nathan (2008-10-13)
      Understanding why the performance of a multithreaded program does not improve linearly with the number of cores in a sharedmemory node populated with one or more multicore processors is a problem of growing practical importance. This paper makes three contributions to performance analysis of multithreaded programs. First, we describe how to measure ...
    • Effective Static Debugging via Componential Set-Based Analysis 

      Flanagan, Cormac (1997-08-28)
      Sophisticated software systems are inherently complex. Understanding, debugging and maintaining such systems requires inferring high-level characteristics of the system's behavior from a myriad of low-level details. For large systems, this quickly becomes an extremely difficult task. MrSpidey is a static debugger that augments the programmers ability ...
    • Efficient Distributed Shared Memory Based on Multi-Protocol Release Consistency 

      Carter, John B. (1994-01)
      A distributed shared memory (DSM) system allows shared memory parallel programs to be executed on distributed memory multiprocessors. The challenge in building a DSM system is to achieve good performance over a wide range of shared memory programs without requiring extensive modifications to the source code. The performance challenge translates into ...
    • Efficient Reorganization of Binary Search Trees 

      Hofri, Micha; Shachnai, Hadas (1996-11-13)
      We consider the problem of maintaining a binary search tree that minimizes the average access cost needed to satisfy randomly generated requests. We analyze scenarios in which the accesses are generated according to a vector of fixed probabilities which is unknown. Our approach is statistical. We devise policies for modifying the tree structure ...
    • Efficient Selection of Vector Instructions using Dynamic Programming 

      Barik, Rajkishore; Sarkar, Vivek; Zhao, Jisheng (2010-06-17)
      Accelerating program performance via SIMD vector units is very common in modern processors, as evidenced by the use of SSE, MMX, VSE, and VSX SIMD instructions in multimedia, scientific, and embedded applications. To take full advantage of the vector capabilities, a compiler needs to generate efficient vector code automatically. However, most commercial ...
    • Elastic Tasks: Unifying Task Parallelism and SPMD Parallelism with an Adaptive Runtime 

      Agrawal, Kunal; Sarkar, Vivek; Sbîrlea, Alina (2015-02-11)
      In this paper, we introduce elastic tasks, a new high-level parallel programming primitive that can be used to unify task parallelism and SPMD parallelism in a common adaptive scheduling framework. Elastic tasks are internally parallel tasks and can run on a single worker or expand to take over multiple workers. An elastic task can be an ordinary ...
    • End-to-End TCP Congestion Control over ATM Networks 

      Aron, Mohit; Druschel, Peter (1997-02-12)
      It is well documented that the effective throughput of TCP can suffer on plain ATM networks. Several research efforts have aimed at developing additions to ATM networks like Early Packet Discard that avoid TCP throughput degradation. This paper instead investigates improvements to TCP that allow it to perform well on ATM networks without switch-level ...
    • Evaluating a Model for Cache Conflict Miss Prediction 

      Kennedy, Ken; Qasem, Apan (2005-04-10)
      Cache conflict misses can cause severe degradation in application performance. Previous research has shown that for many scientific applications majority of cache misses are due to conflicts in cache. Although, conflicts in cache are a major concern for application performance it is often difficult to eliminate them completely. Eliminating conflict ...
    • Exploiting Internet Delay Space Properties for Sybil Attack Mitigation 

      Ng, T. S. Eugene; Zhang, Bo (2008-06-02)
      Recent studies have discovered that the Internet delay space has many interesting properties such as triangle inequality violations (TIV), clustering structures, and constrained growth. Understanding these properties has so far benefited the design of network models and network-performance-aware systems. In this paper, we consider an interesting, ...
    • Exploring the Potential for Accelerating Sparse Matrix-Vector Product on a Processing-in-Memory Architecture 

      Youssefi, Annahita (2008-03-12)
      As the importance of memory access delays on performance has mushroomed over the last few decades, researchers have begun exploring Processing-in-Memory (PIM) technology, which offers higher memory bandwidth, lower memory latency, and lower power consumption. In this study, we investigate whether an emerging PIM design from Sandia National Laboratories ...