Surrogate models can play a pivotal role in enhancing performance in contemporary High-Performance Computing applications. Cache-based surrogates use already calculated simulation results to interpolate or extrapolate further simulation output values. But this approach only pays off if the access time to retrieve the needed values is much faster than the actual simulation. While the most existing key-value stores use a Client-Server architecture with dedicated storage nodes, this is not the most suitable architecture for HPC applications. Instead, we propose a distributed architecture where the parallel processes offer a part of their available memory to build a shared distributed hash table based on MPI. This paper presents three DHT approaches with the special requirements of HPC applications in mind. The presented lock-free design outperforms both DHT versions which use explicit synchronization by coarse-grained resp. fine-grained locking. The lock-free DHT shows very good scaling regarding read and write performance. The runtime of a coupled reactive transport simulation was improved between 14% and 42% using the lock-free DHT as a surrogate model.

翻译：替代模型在提升当代高性能计算应用性能方面可发挥关键作用。基于缓存的替代模型利用已计算完成的模拟结果，通过插值或外推方法预测后续模拟输出值。但只有当检索所需数值的访问时间远快于实际模拟计算时，该方法才具有实际效益。现有大多数键值存储系统采用配备专用存储节点的客户端-服务器架构，这种架构并不最适合高性能计算应用。为此，我们提出一种分布式架构，其中并行进程贡献部分可用内存，基于MPI构建共享的分布式哈希表。本文针对高性能计算应用的特殊需求，提出三种分布式哈希表实现方案。所提出的无锁设计在读写性能上均优于采用显式同步机制的粗粒度锁与细粒度锁两种分布式哈希表版本。无锁分布式哈希表在读写性能方面展现出优异的可扩展性。将无锁分布式哈希表作为替代模型应用于耦合反应输运模拟，可使运行时间提升14%至42%。