GPU集群下第一原理非局部映射势能计算

First-principle nonlocal projector potential calculation on GPU cluster

平面波赝势密度泛函(PWP-DFT)计算是材料计算中应用最广泛的方法,其中映射计算是PWP-DFT方法求解自洽迭代中重要的一部分。针对映射势能计算成为软件加速的瓶颈,提出了针对该部分的图形处理器(GPU)加速算法,其中考虑GPU的特点:1)使用了新的并行机制求解非局部映射势能;2)重新设计了数据分布结构;3)减少内存的使用;4)提出了一种解决算法中数据相关问题的方法。最终获得了18～57倍加速,使每步分子动力学模拟最终降为12 s。详细分析了该模块在GPU平台上的测试时间,同时对该算法在GPU集群上的计算瓶颈进行了讨论。

Plane Wave Pseudopotential （PWP） Density Functional Theory （DFT） calculation is the most widely used method for material calculation. The projector calculation plays an important part in PWP-DFT calculation for the self- consistent iteration solution, while it often becomes a hinder to the speed-up of software. Therefore, according to the features of Graphic Processing Unit （GPU）, a speed-up algorithm was proposed： 1） using a new parallel mechanism to solve the potential energy of nonlocal projector, 2） redesigning the distribution structure of data, 3） reducing the use of computer memory, 4） Proposing a solution to the related data problems of the algorithm. Eventually got 18 -57 times acceleration, and reached the 12 seconds per step of the molecular dynamics simulation. In this paper, the testing time of running this model on GPU platform was analysed in detail, meanwhile the calculation bottleneck of the implementation of this method into GPU clusters was discussed