A Checkpointing Method with Small Checkpoint Latency

Abstract

The cost of checkpointing consists of checkpoint overhead and checkpoint latency. The former is the time to stop the process for checkpointing. The latter is the time to complete the checkpointing including background checkpointing which stores memory pages. The large checkpoint latency increases the possibility that the error occurs in background checkpointing, which leads to long rollback distance. The method for small checkpoint latency has not been proposed yet. This paper proposes a checkpointing method which achieves small checkpoint latency. The proposed method divides a checkpoint interval into several subcheckpoint intervals. By using the history of memory page modification in subcheckpoint intervals, the proposed method saves some pages which are not expected to be modified in the rest of checkpoint interval in advance. Computer simulation says that the proposed method can reduce the checkpoint latency by 25% comparing to the existing methods.