On Fair Scheduling of Heterogeneous Workloads

This paper describes a new resource allocation policy for partitioning the cycles of a multiprocessor among concurrent multi-threaded jobs, together with a novel scheduler implementation in the Linux kernel. Each job consists of tasks whose execution times are drawn from some discrete distribution. Our policy shifts the established application-centric allocation to task-centric allocation by treating the server as a set of logical servers and dividing their joint resources fairly. We maximize task throughput while maintaining client fairness. We designed and developed the OPT scheduler for the Linux kernel, and obtain significant gains in resource utilization over CFS for various workloads. Our OPT scheduler adapts to dynamic workloads and can schedule multi-threaded clients efficiently to implement our resource allocation policy.