Download or read book Program Transformations for Cache Locality Enhancement on Shared memory Multiprocessors written by and published by . This book was released on 1997 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Program Transformations for Cache Locality Enhancement on Shared memory Multiprocessors written by Naraig Manjikian and published by . This book was released on 1997 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation proposes and evaluates compiler techniques that enhance cache locality and consequently improve the performance of parallel applications on shared-memory multiprocessors. These techniques target applications with loop-level parallelism that can be detected and exploited automatically by a compiler. Novel program transformations are combined with appropriate loop scheduling in order to exploit data reuse while maintaining parallelism and avoiding cache conflicts. First, this dissertation proposes the shift-and-peel transformation for enabling loop fusion and exploiting reuse across parallel loops. The shift-and-peel transformation overcomes dependence limitations that have previously prevented loops from being fused legally, or prevented legally-fused loops from being parallelized. Therefore, this transformation exploits all reuse across loops without loss of parallelism. Second, this dissertation describes and evaluates adaptations of static loop scheduling strategies to exploit wavefront parallelism while ensuring locality in tiled loops. Wavefront parallelism results when tiling is enabled by combining the shift-and-peel transformation with loop skewing. Proper scheduling exploits both intratile and intertile data reuse when independent tiles are executed in parallel on a large number of processors. Third, this dissertation proposes cache partitioning for preventing cache conflicts between data from different arrays, especially when exploiting reuse across loops. Specifically, cache partitioning prevents frequently-recurring conflicts in loops with compatible data access patterns. Cache partitioning transforms the data layout such that there are no conflicts for reused data from different arrays during loop execution. An analytical model is also presented to assess the potential benefit of locality enhancement. This model estimates the expected reduction in execution time by parameterizing the reduction in the number of memory accesses with locality enhancement and the contribution of memory accesses towards execution time. Experimental results show that the proposed techniques improve parallel performance by 20%-60% for representative applications on contemporary multiprocessors. The results also show that significant improvements are obtained in conjunction with other performance-enhancing techniques such as prefetching. The importance of the techniques described in this dissertation will continue to increase as processor performance continues to increase more rapidly than memory performance.

Download or read book Languages Compilers and Run Time Systems for Scalable Computers written by David O'Hallaron and published by Springer. This book was released on 2003-06-29 with total page 420 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book constitutes the strictly refereed post-workshop proceedings of the 4th International Workshop on Languages, Compilers, and Run-Time Systems for Scalable Computing, LCR '98, held in Pittsburgh, PA, USA in May 1998. The 23 revised full papers presented were carefully selected from a total of 47 submissions; also included are nine refereed short papers. All current issues of developing software systems for parallel and distributed computers are covered, in particular irregular applications, automatic parallelization, run-time parallelization, load balancing, message-passing systems, parallelizing compilers, shared memory systems, client server applications, etc.

Download or read book The Cache Coherence Problem in Shared Memory Multiprocessors written by Igor Tartalja and published by Wiley-IEEE Computer Society Press. This book was released on 1996-02-13 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book illustrates state-of-the-art software solutions for cache coherence maintenance in shared-memory multiprocessors. It begins with a brief overview of the cache coherence problem and introduces software solutions to the problem. The text defines and details static and dynamic software schemes, techniques for modeling performance evaluation mechanisms, and performance evaluation studies.

Download or read book Encyclopedia of Parallel Computing written by David Padua and published by Springer Science & Business Media. This book was released on 2011-09-08 with total page 2211 pages. Available in PDF, EPUB and Kindle. Book excerpt: Containing over 300 entries in an A-Z format, the Encyclopedia of Parallel Computing provides easy, intuitive access to relevant information for professionals and researchers seeking access to any aspect within the broad field of parallel computing. Topics for this comprehensive reference were selected, written, and peer-reviewed by an international pool of distinguished researchers in the field. The Encyclopedia is broad in scope, covering machine organization, programming languages, algorithms, and applications. Within each area, concepts, designs, and specific implementations are presented. The highly-structured essays in this work comprise synonyms, a definition and discussion of the topic, bibliographies, and links to related literature. Extensive cross-references to other entries within the Encyclopedia support efficient, user-friendly searchers for immediate access to useful information. Key concepts presented in the Encyclopedia of Parallel Computing include; laws and metrics; specific numerical and non-numerical algorithms; asynchronous algorithms; libraries of subroutines; benchmark suites; applications; sequential consistency and cache coherency; machine classes such as clusters, shared-memory multiprocessors, special-purpose machines and dataflow machines; specific machines such as Cray supercomputers, IBM’s cell processor and Intel’s multicore machines; race detection and auto parallelization; parallel programming languages, synchronization primitives, collective operations, message passing libraries, checkpointing, and operating systems. Topics covered: Speedup, Efficiency, Isoefficiency, Redundancy, Amdahls law, Computer Architecture Concepts, Parallel Machine Designs, Benmarks, Parallel Programming concepts & design, Algorithms, Parallel applications. This authoritative reference will be published in two formats: print and online. The online edition features hyperlinks to cross-references and to additional significant research. Related Subjects: supercomputing, high-performance computing, distributed computing

Download or read book Optimizing for Parallelism and Data Locality written by Rice University. Dept. of Computer Science and published by . This book was released on 1992 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: "Previous research has used program transformation to introduce parallelism and to exploit data locality. Unfortunately, these two objectives have usually been considered independently. This work explores the trade-offs between effectively utilizing parallelism and memory hierarchy on shared-memory multiprocessors. We present a simple, but suprisingly accurate, memory model to determine cache line reuse from both multiple accesses to the same memory location and from consecutive memory access. The model is used in memory optimizing and loop parallelization algorithms that effectively exploit data locality and parallelism in concert. We demonstrate the efficacy of this approach with very encouraging experimental results."

Download or read book Cache Memory Design and Performance Issues in Shared memory Multiprocessors written by Farnaz Mounes-Toussi and published by . This book was released on 1995 with total page 358 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Compiler Optimizations for Cache Locality and Coherence written by University of Rochester. Dept. of Computer Science and published by . This book was released on 1994 with total page 29 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: "Almost every modern processor is designed with a memory hierarchy organized into several levels, each of which is smaller, faster, and more expensive than the level below. High performance requires the effective use of the cached data, i.e. cache locality. Smart compiler transformations can relieve the programmer from hand-optimizing for the specific machine architectures. In a multiprocessor system, data inconsistency may occur between memory and caches. For example, the memory and multiple caches may have inconsistent copies of the same cache block. This introduces the problem of cache coherence. Several cache coherence protocols have been developed to maintain data coherence for multiple processors. Since multiple variables are located in the same block, it may cause the problem of false sharing, which has been identified by many researchers as a major obstacle to high performance. Therefore, in a multiprocessor system, we need to avoid false sharing as well as exploit cache locality. In this paper, we first develop a new data reuse model and an algorithm called height reduction to improve cache locality. The advantage of this algorithm is that it can improve band matrix programs as well as dense matrix programs. It is more accurate and general than the existing techniques on improving cache locality, which were developed to optimize dense matrix programs. Then with the height reduction algorithm, we extend loop tiling to exploit not only intra-tile data locality but also inter-tile data locality. We call the new tiling affinity tiling. Our experiments show that affinity tiling is less sensitive to the choice of the tile size. Finally, we show that the algorithm also helps to eliminate or reduce false sharing in multiprocessor systems. With the height reduction algorithm and affinity tiling, significant performance improvement (speedups from 2.5 to 10) has been ovserved on HP workstations and KSR1 multiprocessors."

Download or read book Cache and Interconnect Architectures in Multiprocessors written by Michel Dubois and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cache And Interconnect Architectures In Multiprocessors Eilat, Israel May 25-261989 Michel Dubois UniversityofSouthernCalifornia Shreekant S. Thakkar SequentComputerSystems The aim of the workshop was to bring together researchers working on cache coherence protocols for shared-memory multiprocessors with various interconnect architectures. Shared-memory multiprocessors have become viable systems for many applications. Bus based shared-memory systems (Eg. Sequent's Symmetry, Encore's Multimax) are currently limited to 32 processors. The fIrst goal of the workshop was to learn about the performance ofapplications on current cache-based systems. The second goal was to learn about new network architectures and protocols for future scalable systems. These protocols and interconnects would allow shared-memory architectures to scale beyond current imitations. The workshop had 20 speakers who talked about their current research. The discussions were lively and cordial enough to keep the participants away from the wonderful sand and sun for two days. The participants got to know each other well and were able to share their thoughts in an informal manner. The workshop was organized into several sessions. The summary of each session is described below. This book presents revisions of some of the papers presented at the workshop.

Download or read book High Performance Embedded Architectures and Compilers written by André Seznec and published by Springer. This book was released on 2008-12-24 with total page 432 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book constitutes the refereed proceedings of the Fourth International Conference on High Performance Embedded Architectures and Compilers, HiPEAC 2009, held in Paphos, Cyprus, in January 2009. The 27 revised full papers presented together with 2 invited keynote paper were carefully reviewed and selected from 97 submissions. The papers are organized in topical sections on dynamic translation and optimisation, low level scheduling, parallelism and resource control, communication, mapping for CMPs, power, cache issues as well as parallel embedded applications.

Download or read book LCPC 97 written by David Sehr and published by Springer Science & Business Media. This book was released on 1997-06-11 with total page 632 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the thoroughly refereed post-workshop proceedings of the 9th International Workshop on Languages and Compilers for Parallel Computing, LCPC'96, held in San Jose, California, in August 1996. The book contains 35 carefully revised full papers together with nine poster presentations. The papers are organized in topical sections on automatic data distribution and locality enhancement, program analysis, compiler algorithms for fine-grain parallelism, instruction scheduling and register allocation, parallelizing compilers, communication optimization, compiling HPF, and run-time control of parallelism.

Download or read book Data Placement in Shared virtual memory Multiprocessors with Non Uniform Memory Access Times written by Jayashree Ramanathan and published by . This book was released on 1992 with total page 466 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Languages and Compilers for Parallel Computing written by Keith Cooper and published by Springer Science & Business Media. This book was released on 2011-03-07 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book constitutes the thoroughly refereed post-proceedings of the 23rd International Workshop on Languages and Compilers for Parallel Computing, LCPC 2010, held in Houston, TX, USA, in October 2010. The 18 revised full papers presented were carefully reviewed and selected from 47 submissions. The scope of the workshop spans foundational results and practical experience, and targets all classes of parallel platforms in- cluding concurrent, multithreaded, multicore, accelerated, multiprocessor, and cluster systems.

Download or read book Dissertation Abstracts International written by and published by . This book was released on 2000 with total page 956 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Unifying Data and Control Transformations for Distributed Shared memory Machines written by University of Rochester. Dept. of Computer Science and published by . This book was released on 1994 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: "We present a unified approach to locality optimization that employs both data and control transformations. Data transformations include changing the array layout in memory. Control transformations involve changing the execution order of programs. We have developed new techniques for compiler optimizations for distributed shared-memory machines, although the same techniques can be used for sequential machines with a memory hierarchy. Our compiler optimizations are based on an algebraic representation of data mappings and a new data locality model. We present a pure data transformation algorithm and an algorithm unifying data and control transformations. While there has been much work on control transformations, the opportunities for data transformations have been largely neglected. In fact, data transformations have the advantage of being applicable to programs that cannot be optimized with control transformations. The unified algorithm, which performs data and control transformations simultaneously, offers improvement over optimizations obtained by applying data and control transformations separately. The experimental results using a set of applications on a parallel machine show that the new optimizations improve performance significantly. These results are further analyzed using locality metrics with instrumentation and simulation."

Download or read book Languages and Compilers for Parallel Computing written by Larry Carter and published by Springer. This book was released on 2003-06-29 with total page 511 pages. Available in PDF, EPUB and Kindle. Book excerpt: In August 1999, the Twelfth Workshop on Languages and Compilers for P- allel Computing (LCPC) was hosted by the Hierarchical Tiling Research group from the Computer Science and Engineering Department at the University of California San Diego (UCSD). The workshop is an annual international forum for leading research groups to present their current research activities and the latest results. It has also been a place for researchers and practitioners to - teract closely and exchange ideas about future directions. Among the topics of interest to the workshop are language features, code generation, debugging, - timization, communication and distributed shared memory libraries, distributed object systems, resource management systems, integration of compiler and r- time systems, irregular and dynamic applications, and performance evaluation. In 1999, the workshop was held at the International Relations/Paci c Studies Auditorium and the San Diego Supercomputer Center at UCSD. Seventy-seven researchers from Australia, England, France, Germany, Korea, Spain, and the United States attended the workshop, an increase of over 50% from 1998.

Download or read book Reducing False Sharing on Shared Memory Multiprocessors Through Compile Time Data Transformations written by Tor E. Jeremiassen and published by . This book was released on 1994 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: