基于HDF5的结构网格计算流体动力学程序并行I/O技术

摘要

大规模计算流体动力学(CFD)计算对数据L/O能力提出了很高需求.层次式文件格式(HDF5)可有效管理大规模科学数据,并对并行L/O具有良好的支持.针对结构网格CFD并行程序,设计了其数据文件的HDF5存储模式,并基于HDF5并行I/O编程接口实现了其数据文件的并行L/O,在并行计算机系统上进行了性能测试与分析.结果表明,在使用4 ～32个进程时,基于HDF5并行L/O方式的写文件性能比每进程独立写普通文件的方式高6.9～16.1倍；基于HDF5并行I/O方式的读文件性能不及后者,为后者的20％ ～ 70％,但是读文件的时间开销远小于写文件的时间开销,因此对总体性能的影响较小.%Large scale parallel Computational Fluid Dynamics (CFD) simulation has posed high demand on the data I/O capabilities.Hierarchical Data Format version 5 (HDF5) can effectively manage large scale scientific data and has a good support to parallel I/O.The HDF5 data storage model for a parallel CFD application was designed.The parallel I/O method for the application's data was implemented based on the HDF5 parallel I/O API.Performance experiments were performed on a parallel computer system.The results show that the data writing speed of this HDF5 based parallel I/O method outperforms the parallel I/O methods (i.e.each process writes an ordinary data file independently) by 6.9 to 16.1 times,when 4 to 32 processes are used.The data reading speed of this HDF5 based parallel I/O method is slower than the parallel I/O methods,with a speed of 20％ to 70％ times of the latter.However,the cost of data reading time is much smaller than the cost of data writing time,hence has minor effect on the total performance.