Portable Application-level Checkpointing for Hybrid MPI-OpenMP Applications

As parallel machines increase their number of processors, so does the failure rate of the global system, thus, long-running applications will need to make use of fault tolerance techniques to ensure the successful execution completion. Most of current HPC systems are built as clusters of multicores. The hybrid MPI-OpenMP paradigm provides numerous benefits on these systems. This paper presents a checkpointing solution for hybrid MPI-OpenMP applications, in which checkpoint consistency is guaranteed by using a coordination protocol intra-node, while no internode coordination is needed. The proposal reduces network utilization and storage resources in order to optimize the I/O cost of fault tolerance, while minimizing the checkpointing overhead. Besides, the portability of the solution and the dynamic parallelism provided by OpenMP enable the restart of the applications using machines with different architectures, operating systems and/or number of cores, adapting the number of running OpenMP threads for the best exploitation of the available resources. Extensive evaluation using hybrid MPI-OpenMP applications from the ASC Sequoia Benchmark Codes and NERSC-8/Trinity benchmarks is presented, showing the effectiveness and efficiency of the approach.