Enhanced Checkpointing Algorithm for Mobile Applications

Rollback-recovery in mobile systems is important for fault-tolerant computing. Without fault tolerance mechanisms, an application running on a system has to be restarted from scratch if a fault happens in the middle of its execution, resulting in loss of useful computation. To provide efficient rollback-recovery for fault-tolerance in distributed systems, it is significant to reduce the number of checkpoints under the existence of consistent global checkpoints in distributed checkpointing algorithms. Because of the dependencies among the processes states that induced by interprocess communication in distributed systems, asynchronous checkpointing may suffer from the domino effect. Therefore, a consistent global checkpoint should always be ensured to restrict the rollback distance. The quasisynchronous checkpointing protocols achieve synchronization in a loose fashion. The algorithm proposed in this paper follows a new strategy to update the checkpoint interval dynamically.