On the Impact of Interference from Concurrent Jobs on Checkpointing Performance

I/O has been identified as one of the main bottlenecks in HPC. Among the most I/O-intensive operations is checkpointing, which is necessary to save the state of an application and allow it to be restarted at an advanced stage of computation. However, near the parallel file system, concurrency prevents checkpoint phases from reaching the best I/O performance. In this paper, we study I/O interference in this specific context: we look at performance of a checkpoint phase when faced with different interference patterns, exploring aspects such as scale, number of processes, operation, number of files, etc. Through an extensive experimentation, in two systems, we show the impact of these aspects on checkpoint. Moreover, we show that some configurations — e.g., an application that does random accesses — lead to degraded system I/O performance. This paper provides an important background for any effort into mitigating I/O interference and into improving checkpointing performance.