基于集群平台的SAR成像算法多级通信延迟隐藏技术

Technique of hiding multi-level communication latency for SAR imaging algorithm on cluster platform

实时合成孔径雷达(SAR)成像技术是当前军事和遥感领域的研究热点。SAR成像算法具有庞大的数据量和运算量,对高性能计算的需求巨大,适合采用以集群系统为代表的高性能计算机进行性能加速。依据集群系统的分布存储特性,通信延迟是集群上程序性能提升的首要优化因素。为此,以集群系统为平台,深入研究SAR成像算法的多级延迟隐藏技术,重点对线程安全队列、非阻塞通信和多线程分块通信三种关键技术进行研究,并确定了适合于通信延迟隐藏的最优通信块规模。实验结果表明,经过通信延迟隐藏优化的SAR成像程序具有较高的网络利用率,能显著提升性能。

Real-time Synthetic Aperture Radar （SAR） imaging techniques have been attracting many interests in military and remote sensing fields. SAR imaging algorithm features massive data and compu- tation, which presents a huge demand for high performance computing, and thus it is suitable for using a representative high performance architecture, such as the cluster platform, to accelerate SAR imaging programs. For the cluster system with distributed memory, the communication latency is an all-impor- tant optimization factor to improve the performance of parallel program. Therefore, based on the cluster platform, the paper studies on the techniques of hiding the multi-level communication latency for SAR imaging algorithm. Especially, three important techniques are researched, including thread safety queue, non-blocking communication, and multi-thread blocking communication. Moreover, the optimal communication size for hiding communication latency is achieved. The experimental results show that the SAR imaging program optimized by hiding communication latency can have high net utilization, and achieve obvious performance improvement.