检索结果-内蒙古大学图书馆

IEEE/ACM 4th Annual Workshop on Emerging Parallel and Distributed Runtime Systems and Middleware (IPDRM)

作者： Chung, Minh Thanh Weidendorfer, Josef Samfass, Philipp Fuerlinger, Karl Kranzlmuller, Dieter Ludwig Maximilians Univ Munchen MNM Team Munich Germany Leibniz Supercomp Ctr LRZ Garching Germany Tech Univ Munich Dept Informat Munich Germany Ludwig Maximilians Univ Munchen MNM Team Leibniz Supercomp Ctr LRZ Munich Germany

ISBN: (纸本)9780738110646

task-based programming models have shown their potential for efficiency and scalability in parallel and distributed systems. With such a model, a parallel application is broken down into a graph of tasks, which are subsequently scheduled for execution. Recently, implementations of task-based models have addressed distributed memory and heterogeneous systems with accelerators. However, the problem of scheduling tasks as well as allocating resources at runtime is still a challenge. In this paper, we propose coordinated and cooperative task scheduling across multiple applications. The main idea is to exploit the application's idle time e.g. from imbalance to serve tasks from another application. The experiments use Chameleon, a task-based framework for reactive tasking in distributed memory systems. In various example scenarios, we show improvements in CPU utilization of 5% - 15% by coordinated scheduling.

关键词： task-based programming model distributed system scheduling resource management task migration

来源：评论

学校读者我要写书评

暂无评论

PureMEM: A Structured programming model for Transiently Powered Computers 19

PureMEM: A Structured Programming Model for Transiently Powe...

引用

34th ACM/SIGAPP Annual International Symposium on Applied Computing (SAC)

作者： Durmaz, Caglar Yildirim, Kasim Sinan Kardas, Geylani Ege Univ Int Comp Inst Izmir Turkey Ege Univ Dept Comp Engn Izmir Turkey

ISBN: (纸本)9781450359337

Advances in energy harvesting circuits and energy efficient architecture of processors create the potential for batteryless computing and sensing systems called transiently powered computers. These computers can only operate intermittently due to fluctuating nature of ambient energy. Intermittent operation requires a new programming model that should preserve forward progress and maintain data consistency;which are challenging. We propose a structured task-based programming model;namely PureMEM, to cope with these challenges. We discuss how PureMEM prevents interdependencies caused by the unstructured control encountered in intermittent operation, enables re-usability of the tasks, provides dynamic memory management and supports error handling. We also present intermittent programs to exemplify the features of PureMEM.

关键词： task-based programming model Transiently Powered Computers Embedded Systems and Software Structured programming model

来源：评论

学校读者我要写书评

暂无评论

Harnessing Unreliable Cores In Heterogeneous Architecture: The PyDac programming model and Runtime 44

Harnessing Unreliable Cores In Heterogeneous Architecture: T...

引用

44th Annual IEEE/IFIP International Conference on Dependable Systems and Networks (DSN)

作者： Huang, Bin Sass, Ron DeBardeleben, Nathan Blanchard, Sean Univ N Carolina Reconfigurable Comp Syst Lab Charlotte NC 28223 USA Los Alamos Natl Lab Ultrascale Syst Res Ctr Los Alamos NM USA

ISBN: (纸本)9781479922338

Heterogeneous many-core architectures combined with scratch-pad memories are attractive because they promise better energy efficiency than conventional architectures and a good balance between single-thread performance and multithread throughput. However, programmers will need an environment for finding and managing the large degree of parallelism, locality, and system resilience. We propose a Python-based task parallel programming model called PyDac to support these objectives. PyDac provides a two-level programming model based on the divide-and-conquer strategy. The PyDac runtime system allows threads to be run on unreliable hardware by dynamically checking the results without involvement from the programmer. To test this programming model and runtime, an unconventional heterogeneous architecture consisting of PowerPC and ARM cores was developed and emulated on an FPGA device. We inject faults during the execution of micro-benchmarks and show that through the use of double and triple modular redundancy we are able to complete the benchmarks with the correct results while only incurring a proportional performance penalty.

关键词： Heterogeneous Many-core Processor task-based programming model Soft Error Resilience Fault Tolerance

来源：评论

学校读者我要写书评

暂无评论

Unified fault-tolerance framework for hybrid task-parallel message-passing applications

引用

INTERNATIONAL JOURNAL OF HIGH PERFORMANCE COMPUTING APPLICATIONS 2018年第5期32卷 641-657页

作者： Subasi, Omer Martsinkevich, Tatiana Zyulkyarov, Ferad Unsal, Osman Labarta, Jesus Cappello, Franck Barcelona Supercomp Ctr C Jordi Girona 31 Barcelona 08034 Spain Barcelona Supercomp Ctr Architectural Support Programming Models Grp Barcelona Spain Barcelona Supercomp Ctr Comp Sci Res Dept Barcelona Spain Univ Politecn Cataluna Barcelona Spain Univ Paris Sud INRIA Paris France Argonne Natl Lab Argonne IL 60439 USA

We present a unified fault-tolerance framework for task-parallel message-passing applications to mitigate transient errors. First, we propose a fault-tolerant message-logging protocol that only requires the restart of the task that experienced the error and transparently handles any message passing interface calls inside the task. In our experiments we demonstrate that our fault-tolerant solution has a reasonable overhead, with a maximum observed overhead of 4.5%. We also show that fine-grained parallelization is important for hiding the overheads related to the protocol as well as the recovery of tasks. Secondly, we develop a mathematical model to unify task-level checkpointing and our protocol with system-wide checkpointing in order to provide complete failure coverage. We provide closed formulas for the optimal checkpointing interval and the performance score of the unified scheme. Experimental results show that the performance improvement can be as high as 98% with the unified scheme.

关键词： Fault-tolerance message logging checkpoint/restart task-based programming model optimal checkpointing interval

来源：评论

学校读者我要写书评

暂无评论

Evaluating Data Redistribution in PaRSEC

引用

IEEE TRANSACTIONS ON PARALLEL AND DISTRIBUTED SYSTEMS 2022年第8期33卷 1856-1872页

作者： Cao, Qinglei Bosilca, George Losada, Nuria Wu, Wei Zhong, Dong Dongarra, Jack Univ Tennessee Dept Elect Engn & Comp Sci Knoxiville TN 37996 USA Los Alamos Natl Lab Los Alamos NM 87545 USA

Data redistribution aims to reshuffle data to optimize some objective for an algorithm. The objective can be multi-dimensional, such as improving computational load balance or decreasing communication volume or cost, with the ultimate goal of increasing the efficiency and therefore reducing the time-to-solution for the algorithm. The classic redistribution problem focuses on optimally scheduling communications when reshuffling data between two regular, usually block-cyclic, data distributions. Besides distribution, data size is also a performance-critical parameter because it affects the reshuffling algorithm in terms of cache, communication efficiency, and potential parallelism. In addition, task-based runtime systems have gained popularity recently as a potential candidate to address the programming complexity on the way to exascale. In this scenario, it becomes paramount to develop a flexible redistribution algorithm for task-based runtime systems, which could support all types of regular and irregular data distributions and take data size into account. In this article, we detail a flexible redistribution algorithm and implement an efficient approach in a task-based runtime system, PaRSEC. Performance results show great capability compared to the theoretical bound and ScaLAPACK, and applications highlight an increased efficiency with little overhead in terms of data distribution, data size, and data format.

关键词： task analysis Runtime Distributed databases programming Parallel processing Costs Program processors Data redistribution data distribution data size data format task-based programming model dynamic runtime system high-performance computing

来源：评论

学校读者我要写书评

暂无评论

Abstraction Layer For Standardizing APIs of task-based Engines

引用

IEEE TRANSACTIONS ON PARALLEL AND DISTRIBUTED SYSTEMS 2020年第11期31卷 2482-2495页

作者： Alomairy, Rabab Ltaief, Hatem Abduljabbar, Mustafa Keyes, David King Abdullah Univ Sci & Technol Comp Elect & Math Sci & Engn CEMSE Div Extreme Comp Res Ctr Thuwal 239556900 Saudi Arabia

We introduce AL4SAN, a lightweight library for abstracting the APIs of task-based runtime engines. AL4SAN unifies the expression of tasks and their data dependencies. It supports various dynamic runtime systems relying on compiler technology and user-defined APIs. It enables a single application to employ different runtimes and their respective scheduling components, while providing user-obliviousness to the underlying hardware configurations. AL4SAN exposes common front-end APIs and connects to different back-end runtimes. Experiments on performance and overhead assessments are reported on various shared- and distributed-memory systems, possibly equipped with hardware accelerators. A range of workloads, from compute-bound to memory-bound regimes, are employed as proxies for current scientific applications. The low overhead (less than 10 percent) achieved using a variety of workloads enables AL4SAN to be deployed for fast development of task-based numerical algorithms. More interestingly, AL4SAN enables runtime interoperability by switching runtimes at runtime. Blending runtime systems permits to achieve a twofold speedup on a task-based generalized symmetric eigenvalue solver, relative to state-of-the-art implementations. The ultimate goal of AL4SAN is not to create a new runtime, but to strengthen co-design of existing runtimes/applications, while facilitating user productivity and code portability. The code of AL4SAN is freely available at https://***/ecrc/al4san, with extensions in progress.

关键词： Runtime task analysis Hardware Engines Libraries programming Productivity task-based programming model dynamic runtime systems abstraction layer API standardization user productivity LLVM compiler infrastructure runtime interoperability

来源：评论

学校读者我要写书评

暂无评论

Runtime-Assisted Shared Cache Insertion Policies based on Re-reference Intervals 23rd

Runtime-Assisted Shared Cache Insertion Policies Based on Re...

引用

23rd International Conference on Parallel and Distributed Computing (Euro-Par)

作者： Dimic, Vladimir Moreto, Miquel Casas, Marc Valero, Mateo Barcelona Supercomp Ctr BSC Barcelona Spain Univ Politecn Cataluna Barcelona Spain

ISBN: (纸本)9783319642031;9783319642024

Processor speed is improving at a faster rate than the speed of main memory, which makes memory accesses increasingly expensive. One way to solve this problem is to reduce miss ratio of the processor's last level cache by improving its replacement policy. We approach the problem by co-designing the runtime system and hardware and exploiting the semantics of the applications written in data-flow task-based programming models to provide hardware with information about the task types and task data-dependencies. We propose the task-Type aware Insertion Policy, TTIP, which uses the runtime system to dynamically determine the best probability per task type for bimodal insertion in the recency stack and the static Dependency-Type aware Insertion Policy, DTIP, that inserts cache lines in the optimal position taking into account the dependency types of the current task. TTIP and DTIP perform similarly or better than state-of-the-art replacement policies, while requiring less hardware.

关键词： Shared cache Replacement policy Runtime system task-based programming model Hardware-software co-design

来源：评论

学校读者我要写书评

暂无评论

A Framework to Exploit Data Sparsity in Tile Low-Rank Cholesky Factorization 36

A Framework to Exploit Data Sparsity in Tile Low-Rank Choles...

引用

36th IEEE International Parallel and Distributed Processing Symposium (IEEE IPDPS)

作者： Cao, Qinglei Alomairy, Rabab Pei, Yu Bosilca, George Ltaief, Hatem Keyes, David Dongarra, Jack Univ Tennessee Innovat Comp Lab Knoxville TN 37996 USA King Abdullah Univ Sci & Technol Extreme Comp Res Ctr Div Comp Elect & Math Sci & Engn Thuwal Saudi Arabia Oak Ridge Natl Lab Oak Ridge TN USA Univ Manchester Manchester Lancs England

ISBN: (纸本)9781665481069

We present a general framework that couples the PaRSEC runtime system and the HiCMA numerical library to solve challenging 3D data-sparse problems. Though formally dense, many matrix operators possess a rank structured property that can be exploited during the most time-consuming computational phase, i.e., the matrix factorization. In particular, this work highlights how a software bundle powered by a task-based programming model can address the heterogeneous workloads engendered by compressing the dense operator. Using Tile LowRank (TLR) approximation, our approach consists in capturing the most significant information in each tile of the matrix using a threshold which satisfies the application's accuracy requirements. Matrix operations are performed on the compressed data layout, reducing memory footprint and algorithmic complexity. Our proposed software solution accommodates a range of traditional data structures of linear algebra, i.e., from dense and datasparse to sparse, within a single matrix operation. Separation of concerns is at the heart: hardware-agnostic implementation, asynchronous execution with a dynamic runtime system, and high performance numerical kernels, to prepare scientific applications to embrace exascale opportunities. This ambition necessitates extensions to PaRSEC that incorporate information related to data structure and rank distribution into the runtime decision-making. We introduce two runtime optimizations to address the challenges encountered when confronted with a large rank disparity: (1) a trimming procedure performed at runtime to cut away data dependencies from the directed acyclic graph discovered to be no longer required after compression and (2) a rank-aware diamond-shaped data distribution to mitigate the load imbalance overheads, reduce data movement, and conserve memory footprint. We assess our implementation using 3D unstructured mesh deformation based on Radial Basis Function (RBF) interpolation. We report performance re

关键词： Low-rank approximations task-based programming model Dynamic runtime system HPC Mesh deformations

来源：评论

学校读者我要写书评

暂无评论

Fault-tolerant protocol for hybrid task-parallel message-passing applications

Fault-tolerant protocol for hybrid task-parallel message-pas...

引用

IEEE International Conference on Cluster Computing (CLUSTER)

作者： Martsinkevich, Tatiana Subasi, Omer Unsal, Osman Labarta, Jesus Cappello, Franck Univ Paris 11 INRIA Paris France Barcelona Supercomp Ctr Barcelona Spain Argonne Natl Lab Argonne IL 60439 USA

ISBN: (纸本)9781467365987

We present a fault-tolerant protocol for task parallel message-passing applications to mitigate transient errors. The protocol requires the restart only of the task that experienced the error and transparently handles any MPI calls inside the task. The protocol is implemented in Nanos-a dataflow runtime for task-based OmpSs programming model-and the PMPI profiling layer to fully support hybrid OmpSs+MPI applications. In our experiments we demonstrate that our fault-tolerant solution has a reasonable overhead, with a maximum observed overhead of 4.5%. We also show that fine-grained parallelization is important for hiding the overheads related to the protocol as well as the recovery of tasks.

关键词： fault tolerance high performance computing message logging checkpointing task-based programming model dataflow model

来源：评论

学校读者我要写书评

暂无评论

Optimizing Computation-Communication Overlap in Asynchronous task-based Programs 19

Optimizing Computation-Communication Overlap in Asynchronous...

引用

33rd ACM International Conference on Supercomputing (ICS)

作者： Castillo, Emilio Jain, Nikhil Casas, Marc Moreto, Miquel Schulz, Martin Beivide, Ramon Valero, Mateo Bhatele, Abhinav Barcelona Supercomp Ctr Barcelona Spain Univ Politecn Cataluna Barcelona Spain NVIDIA Inc Santa Clara CA USA Tech Univ Munich Munich Germany Univ Cantabria Barcelona Spain Lawrence Livermore Natl Lab Livermore CA 94550 USA

ISBN: (纸本)9781450360791

Asynchronous task-based programming models are gaining popularity to address the programmability and performance challenges in high performance computing. One of the main attractions of these models and runtimes is their potential to automatically expose and exploit overlap of computation with communication. However, we find that inefficient interactions between these programming models and the underlying messaging layer (in most cases, MPI) limit the achievable computation-communication overlap and negatively impact the performance of parallel programs. We address this challenge by exposing and exploiting information about MPI internals in a task-based runtime system to make better task-creation and scheduling decisions. In particular, we present two mechanisms for exchanging information between MPI and a task-based runtime, and analyze their trade-offs. Further, we present a detailed evaluation of the proposed mechanisms implemented in MPI and a task-based runtime. We show performance improvements of up to 16.3% and 34.5% for proxy applications with point-to-point and collective communication, respectively.

关键词： task-based programming model computation-communication overlap mpi

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：