Dynamic NTP clock synchronization algorithm based on HPC simulation environment

• 1、School of Computer, Beijing University of Posts and Telecommunications, Beijing 100876, China
• 2、Computer, Beijing University of Posts and Telecommunications, Beijing 100876, China

Abstract：HPC interconnect simulation environment is an efficient approach to lower the development cost and shorten development cycles for supercomputer. In this case, we observe that a coherent clock across all nodes is critical to achieve high accuracy of simulation results. However, the devices diversity problem results in relative difference between nodes. To solve the problem, we present a dynamic NTP time synchronization protocol. First, a NTP clock packet monitoring method for each node is implemented. To obtain the clock offset during synchronization period, this method records the each node timestamp before and after synchronization. Based on that, an adaptive adjustment algorithm for synchronizing cycle is proposed. It adjusts each node synchronization cycle dynamically according to the clock offset. Therefore, consensus-based time synchronization across the different nodes is maintained. The experimental results show that the proposed dynamic NTP time synchronization protocol synchronizing the time (the clock) in HPC interconnect simulation environment between nodes efficiently. Compared to the traditional NTP protocol, our methods can ensure time synchronization accuracy in the microsecond range. Moreover, it improves execution efficiency of parallel computing and lighten simulator cluster network loads.

Keywords： high performance computing；simulation environment；virtualization；time synchronization；dynamic NTP