基于索引的准同步检查点的重新计时策略

A Timer-Reset Strategy of Index-Based Quasi-Synchronous Checkpointing

基于索引的分布式检查点算法利用了Lamport逻辑时钟的思想来保证形成全局一致性检查点(或者恢复线)。作为一种准同步方法,基于索引的检查点算法具有异步检查点算法的灵活性,且能像同步算法一样避免多米诺效应。本文在著名的BCS算法的基础上提出了一种减少基本检查点数目的优化策略———重新计时法。最后,通过模拟实验证明了这种改进策略的有效性。

Index-based checkpointing algorithms timestamp the checkpoints with indices that are similar to Lamport's logical clocks to ensure the existence of consistent global checkpoint (or recovery line). As a quasi-synchronous strategy, index-based checkpointing algorithms have the autonomy similar to the asynchronous strategy, while it is domino-effect free like the synchronous algorithm. In this paper the well-known index-based algorithm BCS and some optimization based on it are introduced, then another optimal approach called Timer Reset to reducing the number of basic checkpoints is presented.Finally simulation experiments show that the improved strategy is effective.