The scalability of future massively parallel processing (MPP) systems is being severely challenged by high failure rates. Current hard disk drive (HDD) checkpointing results in overhead of 25% or more at the petascale. With a direct correlation between checkpoint frequencies and node counts, novel techniques that can take more frequent checkpoints with minimum overhead are critical to implement a reliable exascale system. In this work, we leverage the upcoming Phase-Change Random Access Memory (PCRAM) technology and propose a hybrid local/global checkpointing mechanism. After a thorough analysis of MPP systems failure rates and failure sources, we propose three variants of PCRAM-based hybrid checkpointing schemes, DIMM+HDD, DIMM+DIMM, and 3D+3D, which reduce the checkpoint overhead and offer a smooth transition from the conventional pure HDD checkpoint to the ideal 3D PCRAM mechanism. The proposed pure 3D PCRAM-based mechanism can ultimately take checkpoints with overhead less than 4%...
Xiangyu Dong, Naveen Muralimanohar, Norman P. Joup