Download or read book Optimizing Irregular Data Accesses for Cluster and Multicore Architectures written by Jimmy Zhigang Su and published by . This book was released on 2010 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt: Applications with irregular accesses to shared state are one of the most challenging computational patterns in parallel computing. Accesses can involve both read or write operations, with writes having the additional complexity of requiring some form of synchronization. Irregular accesses perform poorly in local cached-based memory systems and across networks in global distributed memory settings, because they have poor spatial and temporal locality. Irregular accesses arises in transaction processing, in various system level programs, in computing histograms, performing sparse matrix operations, updating meshes in particle-mesh methods, and building adaptive unstructured meshes. Writing codes with asynchronous parallel updates on clusters and multicore processors presents different sets of challenges. On clusters, the goal is to minimize the number of messages and the volume of messages between nodes. While on multicore machines, the goal is to minimize off-chip accesses since there is significant performance difference between on chip and off chip memory access. In this dissertation, we explore various analyses, optimizations, and tools for shared accesses on both multicore and distributed memory cluster architectures. On cluster architectures, we consider both irregular reads and writes, demonstrate how Partitioned Global Address Space languages support programming irregular problems, and develop optimizations to minimize communication traffic, both in volume and number of distinct events. On multicore processors, we consider the lower level code generation and tuning problem, independent of any particular source language. We explore performance tradeoffs between various shared update implementations, such as locking, replication of state to avoid collisions, and hybrid versions. We develop an adaptive implementation that adjusts the shared update strategy based on densities that yields significant speedups. In addition, we develop a performance debugging tool to find scalability problems in large scientific applications early in the development cycle. Throughout the thesis we perform experiments demonstrating the value of our optimizations and tools in both architectural settings, use a set of benchmarks and applications that include histogram making, sparse matrix computations, and two scientific simulations involving particle-mesh methods. Our results show substantial speeds of up to 4.8X for multicore platforms and 120X for clusters. The results are a comprehensive set of techniques for improving the performance of irregular applications using advanced languages, compilers, analyses, optimizations and tools.

Download or read book Algorithms and Architectures for Parallel Processing written by Zahir Tari and published by Springer Nature. This book was released on with total page 525 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Optimizing Memory Systems for High Efficiency in Computing Clusters written by Wenjie Liu and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: DRAM-based memory system suffers from increasing aggravating row buffer interference, which causes significant performance degradation and power consumption. With DRAM scaling, the overheads of row buffer interference become even worse due to higher row activation and precharge latency. Clusters have been a prevalent and successful computing framework for processing large amount of data due to their distributed and parallelized working paradigm. A task submitted to a cluster is typically divided into a number of subtasks which are designated to different work nodes running the same code but dealing with different equal portion of the dataset to be processed. Due to the existence of heterogeneity, it could easily result in stragglers unfairly slowing down the entire processing, because work nodes finish their subtasks at different rates. With the increasing problem complexity, more irregular applications are deployed on high-performance clusters due to the parallel working paradigm, and yield irregular memory access behaviors across nodes. However, the irregularity of memory access behaviors is not comprehensively studied, which results in low utilization of the integrated hybrid memory system compositing of stacked DRAM and off-chip DRAM. This dissertation lists our research results on the above three mentioned challenges in order to optimize the memory system for high efficiency in computing clusters. Details are as follows: To address low row buffer utilization caused by row buffer interference, we propose Row Buffer Cache (RBC) architecture to efficiently mitigate row buffer interference overheads. At the core of the RBC architecture, the DRAM pages with good locality are cached and escape from the row buffer interference.Such an RBC architecture significantly reduces the overheads caused by row activation and precharge, thus improves overall system performance and energy efficiency. We evaluate our RBC using SPEC CPU2006 on a DDR4 memory compared to the commodity baseline memory system along with the state-of-art methods, DICE and Bingo. Results show that RBC improves the memory performance by up to 2.24X (16.1% on average) and reduces the overall memory energy by up to 68.2% (23.6% on average) for single-core simulations. For multi-core simulations, RBC increases the performance by up to 1.55X (16.7% on average) and reduces the energy by up to 35.4% (21.3% on average). Comparing with the state-of-art methods, RBC outperforms DICE and Bingo by 8% and 5.1% on average for single-core scenario, and by 10.1% and 4.7% for multi-core scenario. To relax the straggling effect observed in clusters, we aim to speed up straggling work nodes to quicken the overall processing by leveraging exhibited performance variation, and propose StragglerHelper which conveys the memory access characteristics experienced by the forerunner to the stragglers such that stragglers can be sped up due to the accurately informed memory prefetching. A Progress Monitor is deployed to supervise the respective progresses of the work nodes and inform the memory access patterns of forerunner to straggling nodes. Our evaluation results with the SPEC MPI 2007 and BigDataBench on a cluster of 64 work nodes have shown that StragglerHelper is able to improve the execution time of stragglers by up to 99.5% with an average of 61.4%, contributing to an overall improvement of the entire cohort of the cluster by up to 46.7% with an average of 9.9% compared to the baseline cluster. To address the performance difference in the irregular application, we devise a novel method called Similarity-Managed Hybrid Memory System (SM-HMS) to improve the hybrid memory system performance by leveraging the memory access similarity among nodes in a cluster. Within SM-HMS, two techniques are proposed, Memory Access Similarity Measuring and Similarity-based Memory Access Behavior Sharing. To quantify the memory access similarity, memory access behaviors of each node are vectorized, and the distance between two vectors is used as the memory access similarity. The calculated memory access similarity is used to share memory access behaviors precisely across nodes. With the shared memory access behaviors, SM-HMS divides the stacked DRAM into two sections, the sliding window section and the outlier section. The shared memory access behaviors guide the replacement of the sliding window section while the outlier section is managed in the LRU manner. Our evaluation results with a set of irregular applications on various clusters consisting of up to 256 nodes have shown that SM-HMS outperforms the state-of-the-art approaches, Cameo, Chameleon, and Hyrbid2, on job finish time reduction by up to 58.6%, 56.7%, and 31.3%, with 46.1%, 41.6%, and 19.3% on average, respectively. SM-HMS can also achieve up to 98.6% (91.9% on average) of the ideal hybrid memory system performance.

Download or read book Multicore Processors and Systems written by Stephen W. Keckler and published by Springer Science & Business Media. This book was released on 2009-08-29 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt: Multicore Processors and Systems provides a comprehensive overview of emerging multicore processors and systems. It covers technology trends affecting multicores, multicore architecture innovations, multicore software innovations, and case studies of state-of-the-art commercial multicore systems. A cross-cutting theme of the book is the challenges associated with scaling up multicore systems to hundreds of cores. The book provides an overview of significant developments in the architectures for multicore processors and systems. It includes chapters on fundamental requirements for multicore systems, including processing, memory systems, and interconnect. It also includes several case studies on commercial multicore systems that have recently been developed and deployed across multiple application domains. The architecture chapters focus on innovative multicore execution models as well as infrastructure for multicores, including memory systems and on-chip interconnections. The case studies examine multicore implementations across different application domains, including general purpose, server, media/broadband, network processing, and signal processing. Multicore Processors and Systems is the first book that focuses solely on multicore processors and systems, and in particular on the unique technology implications, architectures, and implementations. The book has contributing authors that are from both the academic and industrial communities.

Download or read book Smart Multicore Embedded Systems written by Massimo Torquati and published by Springer Science & Business Media. This book was released on 2013-11-09 with total page 194 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a single-source reference to the state-of-the-art of high-level programming models and compilation tool-chains for embedded system platforms. The authors address challenges faced by programmers developing software to implement parallel applications in embedded systems, where very often they are forced to rewrite sequential programs into parallel software, taking into account all the low level features and peculiarities of the underlying platforms. Readers will benefit from these authors’ approach, which takes into account both the application requirements and the platform specificities of various embedded systems from different industries. Parallel programming tool-chains are described that take as input parameters both the application and the platform model, then determine relevant transformations and mapping decisions on the concrete platform, minimizing user intervention and hiding the difficulties related to the correct and efficient use of memory hierarchy and low level code generation.

Download or read book Computational Sciences written by Ponnadurai Ramasami and published by Walter de Gruyter GmbH & Co KG. This book was released on 2017-10-23 with total page 250 pages. Available in PDF, EPUB and Kindle. Book excerpt: Eleven carefully selected, peer-reviewed contributions from the Virtual Conference on Computational Science (VCCS-2016) are featured in this edited book of proceedings. VCCS-2016, an annual meeting, was held online from 1st to 31st August 2016. The theme of the conference was "Computational Thinking for the Advancement of Society" and it matched the paradigm shift in the way we think. VCCS-2016 was attended by 100 participants from 20 countries. The chapters reflect a wide range of fundamental and applied research applying computational methods.

Download or read book Euro Par 2010 Parallel Processing Workshops written by Mario R. Guarracino and published by Springer. This book was released on 2011-06-24 with total page 684 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book constitutes thoroughly refereed post-conference proceedings of the workshops of the 16th International Conference on Parallel Computing, Euro-Par 2010, held in Ischia, Italy, in August/September 2010. The papers of these 9 workshops HeteroPar, HPCC, HiBB, CoreGrid, UCHPC, HPCF, PROPER, CCPI, and VHPC focus on promotion and advancement of all aspects of parallel and distributed computing.

Download or read book Large Scale Network Centric Distributed Systems written by Hamid Sarbazi-Azad and published by John Wiley & Sons. This book was released on 2013-10-10 with total page 586 pages. Available in PDF, EPUB and Kindle. Book excerpt: A highly accessible reference offering a broad range of topics and insights on large scale network-centric distributed systems Evolving from the fields of high-performance computing and networking, large scale network-centric distributed systems continues to grow as one of the most important topics in computing and communication and many interdisciplinary areas. Dealing with both wired and wireless networks, this book focuses on the design and performance issues of such systems. Large Scale Network-Centric Distributed Systems provides in-depth coverage ranging from ground-level hardware issues (such as buffer organization, router delay, and flow control) to the high-level issues immediately concerning application or system users (including parallel programming, middleware, and OS support for such computing systems). Arranged in five parts, it explains and analyzes complex topics to an unprecedented degree: Part 1: Multicore and Many-Core (Mc) Systems-on-Chip Part 2: Pervasive/Ubiquitous Computing and Peer-to-Peer Systems Part 3: Wireless/Mobile Networks Part 4: Grid and Cloud Computing Part 5: Other Topics Related to Network-Centric Computing and Its Applications Large Scale Network-Centric Distributed Systems is an incredibly useful resource for practitioners, postgraduate students, postdocs, and researchers.

Download or read book Applied Reconfigurable Computing Architectures Tools and Applications written by Nikolaos Voros and published by Springer. This book was released on 2018-04-25 with total page 761 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book constitutes the proceedings of the 14th International Conference on Applied Reconfigurable Computing, ARC 2018, held in Santorini, Greece, in May 2018. The 29 full papers and 22 short presented in this volume were carefully reviewed and selected from 78 submissions. In addition, the volume contains 9 contributions from research projects. The papers were organized in topical sections named: machine learning and neural networks; FPGA-based design and CGRA optimizations; applications and surveys; fault-tolerance, security and communication architectures; reconfigurable and adaptive architectures; design methods and fast prototyping; FPGA-based design and applications; and special session: research projects.

Download or read book Data Intensive Computing written by Ian Gorton and published by Cambridge University Press. This book was released on 2013 with total page 299 pages. Available in PDF, EPUB and Kindle. Book excerpt: Describes principles of the emerging field of data-intensive computing, along with methods for designing, managing and analyzing the big data sets of today.

Download or read book Proceedings of the 4th Many Core Applications Research Community MARC Symposium written by Peter Tröger and published by Universitätsverlag Potsdam. This book was released on 2012 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt: In continuation of a successful series of events, the 4th Many-core Applications Research Community (MARC) symposium took place at the HPI in Potsdam on December 8th and 9th 2011. Over 60 researchers from different fields presented their work on many-core hardware architectures, their programming models, and the resulting research questions for the upcoming generation of heterogeneous parallel systems.

Download or read book Solving Software Challenges for Exascale written by Stefano Markidis and published by Springer. This book was released on 2015-02-18 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains the thoroughly refereed post-conference proceedings of the Second International Conference on Exascale Applications and Software, EASC 2014, held in Stockholm, Sweden, in April 2014. The 6 full papers presented together with 6 short papers were carefully reviewed and selected from 17 submissions. They are organized in two topical sections named: toward exascale scientific applications and development environment for exascale applications.

Download or read book Euro Par 2016 Parallel Processing written by Pierre-François Dutot and published by Springer. This book was released on 2016-08-10 with total page 711 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book constitutes the refereed proceedings of the 22nd International Conference on Parallel and Distributed Computing, Euro-Par 2016, held in Grenoble, France, in August 2016. The 47 revised full papers presented together with 2 invited papers and one industrial paper were carefully reviewed and selected from 176 submissions. The papers are organized in 12 topical sections: Support Tools and Environments; Performance and Power Modeling, Prediction and Evaluation; Scheduling and Load Balancing; High Performance Architectures and Compilers; Parallel and Distributed Data Management and Analytics; Cluster and Cloud Computing; Distributed Systems and Algorithms; Parallel and Distributed Programming, Interfaces, Languages; Multicore and Manycore Parallelism; Theory and Algorithms for Parallel Computation and Networking; Parallel Numerical Methods and Applications; Accelerator Computing.

Download or read book Big Data Optimization Recent Developments and Challenges written by Ali Emrouznejad and published by Springer. This book was released on 2016-05-26 with total page 492 pages. Available in PDF, EPUB and Kindle. Book excerpt: The main objective of this book is to provide the necessary background to work with big data by introducing some novel optimization algorithms and codes capable of working in the big data setting as well as introducing some applications in big data optimization for both academics and practitioners interested, and to benefit society, industry, academia, and government. Presenting applications in a variety of industries, this book will be useful for the researchers aiming to analyses large scale data. Several optimization algorithms for big data including convergent parallel algorithms, limited memory bundle algorithm, diagonal bundle method, convergent parallel algorithms, network analytics, and many more have been explored in this book.

Download or read book Supercomputing written by Julian Martin Kunkel and published by Springer. This book was released on 2014-06-03 with total page 521 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book constitutes the refereed proceedings of the 29th International Supercomputing Conference, ISC 2014, held in Leipzig, Germany, in June 2014. The 34 revised full papers presented together were carefully reviewed and selected from 79 submissions. The papers cover the following topics: scalable applications with 50K+ cores; advances in algorithms; scientific libraries; programming models; architectures; performance models and analysis; automatic performance optimization; parallel I/O and energy efficiency.

Download or read book Data Intensive Text Processing with MapReduce written by Jimmy Lin and published by Springer Nature. This book was released on 2022-05-31 with total page 171 pages. Available in PDF, EPUB and Kindle. Book excerpt: Our world is being revolutionized by data-driven methods: access to large amounts of data has generated new insights and opened exciting new opportunities in commerce, science, and computing applications. Processing the enormous quantities of data necessary for these advances requires large clusters, making distributed computing paradigms more crucial than ever. MapReduce is a programming model for expressing distributed computations on massive datasets and an execution framework for large-scale data processing on clusters of commodity servers. The programming model provides an easy-to-understand abstraction for designing scalable algorithms, while the execution framework transparently handles many system-level details, ranging from scheduling to synchronization to fault tolerance. This book focuses on MapReduce algorithm design, with an emphasis on text processing algorithms common in natural language processing, information retrieval, and machine learning. We introduce the notion of MapReduce design patterns, which represent general reusable solutions to commonly occurring problems across a variety of problem domains. This book not only intends to help the reader "think in MapReduce", but also discusses limitations of the programming model as well. Table of Contents: Introduction / MapReduce Basics / MapReduce Algorithm Design / Inverted Indexing for Text Retrieval / Graph Algorithms / EM Algorithms for Text Processing / Closing Remarks

Download or read book Analysis and Applications of Lattice Boltzmann Simulations written by Valero-Lara, Pedro and published by IGI Global. This book was released on 2018-05-04 with total page 461 pages. Available in PDF, EPUB and Kindle. Book excerpt: Programming has become a significant part of connecting theoretical development and scientific application computation. Fluid dynamics provide an important asset in experimentation and theoretical analysis. Analysis and Applications of Lattice Boltzmann Simulations provides emerging research on the efficient and standard implementations of simulation methods on current and upcoming parallel architectures. While highlighting topics such as hardware accelerators, numerical analysis, and sparse geometries, this publication explores the techniques of specific simulators as well as the multiple extensions and various uses. This book is a vital resource for engineers, professionals, researchers, academics, and students seeking current research on computational fluid dynamics, high-performance computing, and numerical and flow simulations.