We address the problem of assigning non-partitioned les in a parallel I/O system where the le accesses exhibit Poisson arrival rates and xed service times. We present two new le assignment algorithms based on open queueing networks which aim at simultaneously minimizing simultaneously the load balance across all disks as well as the variance of the service time at each disk. We rst present an o -line algorithm, Sort Partition, which assigns to each disk les with similar access time. Next we show that, assuming that a perfectly balanced le assignment can be found for a given set of les, Sort Partition will nd the le assignment with minimal mean response time. We then present an on-line algorithm, Hybrid Partition, that assigns groups of les with similar service times in successive intervals while guaranteeing that the load imbalance at any point does not exceed a certain threshold. We report on synthetic experiments which exhibit skew in le accesses and sizes, and we compare the performance of our new algorithms with the vanilla greedy le allocation algorithm.
Lee et al. REF propose two file assignment algorithms that balance the load across all disks.
File Assignment in Parallel I/O Systems with Minimal Variance of Service Time
IEEE Trans. on Computers
Computer Science