Strategy for data-flow synchronizations in stencil parallel computations on multi-/manycore systems

Abstract

In this paper, an innovative strategy for the data-flow synchronization in shared-memory systems is proposed. This strategy assumes to synchronize only interdependent threads instead of using the barrier approach that-in contrast to our approach-synchronize all threads. We demonstrate the adaptation of the data-flow synchronization strategy to two complex scientific applications based on stencil codes. An algorithm for the data-flow synchronization is developed and successfully used for both applications. The proposed approach is evaluated for various Intel microarchitectures released in the last 5 years, including the newest processors: Skylake and Knights Landing. The important part of this assessment is the performance comparison of the proposed data-flow synchronization with the OpenMP barrier. The experimental results show that the performance of the studied applications can be accelerated up to 1.3 times using the proposed data-flow synchronizations strategy.

Correlation of Performance Optimizations and Energy Consumption for Stencil-Based Application on Intel Xeon Scalable Processors

“…To alleviate the memory-bound nature of MPDATA, we developed [9], [36], [37], [38] a parallelization methodology for MPDATA heterogeneous stencil computations. It contributes to ease the memory and communication bounds, and exploits resources of multicore ccNUMA/SMP systems better.…”

“…As a result, the second scenario is successfully used to reduce inter-processor communications between caches in ccNUMA systems, while the first scenario is applied inside each processor, where the more efficient, local memory hierarchy is utilized for data traffic. Data-flow strategy of synchronization ( [37]) -the main purpose is to synchronize only interdependent threads instead of using the barrier approach that typically synchronizes all threads. This strategy reduces the cost of synchronization since it requires to synchronize radically less number of cores/threads than the barrier approach.…”

Unleashing the performance of ccNUMA multiprocessor architectures in heterogeneous stencil computations

“…Its efficiency becomes critical for the overall performance. For this reason, in our previous work [17] we proposed a novel strategy for the data-flow synchronization in shared memory systems. The main idea of this strategy is to synchronize only interdependent cores assigned to a given work team, instead of using the barrier approach to synchronize all the threads.…”

Special section on parallel programming

“…Halver et al [5] discuss the use of OpenCL as a language for implementation of classical molecular dynamics simulation useful for benchmarking different hardware platforms. Szustak [9] presents an innovative strategy for the data flow synchronization in stencil parallel computations on sharedmemory systems.Acknowledgements The guest editors of this special issue wish to thank the authors for their interesting contributions and the reviewers for useful suggestions. Finally, we would like to express our gratitude to Professor Hamid Arabnia (Editor-in-Chief of The Journal of Supercomputing) for the opportunity to edit this special issue and his great guidance.…”

“…Halver et al [5] discuss the use of OpenCL as a language for implementation of classical molecular dynamics simulation useful for benchmarking different hardware platforms. Szustak [9] presents an innovative strategy for the data flow synchronization in stencil parallel computations on sharedmemory systems.…”