Two checkpointing approaches i.e., coordinated checkpointing and times based checkpointing are widely used in the literature of MDSs. Coordinated checkpointing protocols uses the less checkpoints and domino free but have large coordinated message overheads as processes synchronize by exchanging coordinated message. However, time based protocol requires every process to take checkpoint during checkpointing. Some of the time based protocols defines the timeout period tp. When this timeouts occur, processes take their checkpoint. If the checkpointing interval is too small then multiple checkpoints are transferred from MHs to MSS through wireless link and also checkpointing takes some time to save the application state. This approach increases the checkpointing overheads. On the other hand, if checkpointing interval is too large this may leads to large amount of computational loss during rollback and recovery. As a result time based approach has minimum coordinated messages overheads cost but has high checkpointing cost as it requires large number checkpoints than minimum but coordinated checkpointing approach have minimum checkpointing cost than time based approach but higher coordinated message overheads cost. In this paper, we design an efficient coordinated checkpointing protocol which uses time to indirectly coordinate to minimize the number of coordinated message transmitted through the wireless link and reduces the number of checkpoints nearest to the minimum. The algorithm is non-blocking and minimum process.
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