Near Linear OS Scheduling Optimization for Memory Intensive Workloads on Multi-socket Multi-core servers

Abstract: Multi-socket multi-core servers are used for solving some of the important problems in computing. Remote DRAM accesses can impact performance of certain applications running on such servers. This paper presents a new near linear operating system (OS) scheduling algorithm to reduce the impact of such remote DRAM accesses. By keeping track of the number of local and remote DRAM accesses, using performance counters, for every thread and applying this algorithm, I come up with a new schedule of threads for the next quantum. This new schedule reduces remote DRAM accesses and improves overall performance. I also show that this algorithm is actually linear in the best case. As the algorithm is near-linear it is amenable for implementation in a real operating system.