Coordinated Thread Scheduling for Workstation Clusters Under Windows NT

Coordinated thread scheduling is a critical factor in achieving good performance for tightly-coupled parallel jobs on workstation clusters. We are building a coordinated scheduling system that coexists with the Windows NT scheduler which both provides coordinated scheduling and can generalize to provide a wide range of resource abstractions. We describe the basic approach, called "demand-based coscheduling", and implementation in the context of Windows NT. We report preliminary performance data characterizing the effectiveness of our approach and describe benefits and limitations of our approach.