Poster: Memory-Conscious Collective I/O for Extreme-Scale HPC Systems

The continuing decrease in memory capacity per core and the increasing disparity between core count and off-chip memory bandwidth create significant challenges for I/O operations in exascale systems. The exascale challenges require rethinking collective I/O for the effective exploitation of the correlation among I/O accesses in the exascale system. In this study we introduce a Memory-Conscious Collective I/O considering the constraint of the memory space. 1)Restricts aggregation data traffic within disjointed subgroups 2)Coordinates I/O accesses in intra-node and inter-node layer 3)Determines I/O aggregators at run time considering data distribution and memory consumption among processes.