In the paper,based on the job characteristics and resources availability,an optimistic checkpoint mechanism for dynamic grids(OCM4G) is proposed.It can determine whether to checkpoint a given job running on a given resource node and establish optimal aperiodic checkpoint intervals by applying the knowledge of job characteristics and resource availability.We evaluate OCM4G over a real grid environment(ChinaGrid) and the results show that OCM4G achieves better performance than the periodic checkpoint and the analytical method of calculating aperiodic checkpoint intervals.
