Architectural support for real-time task scheduling in SMT processors

In Simultaneous Multithreaded (SMT) architectures most hardware resources are shared between threads. This provides a good cost/performance trade-off which renders these architectures suitable for use in embedded systems. However, since threads share many resources, they also interfere with each other. As a result, execution times of applications become highly unpredictable and dependent on the context in which an application is executed. Obviously, this poses problems if an SMT is to be used in a real-time system. In this paper, we propose two novel hardware mechanisms that can be used to reduce this performance variability. In contrast to previous approaches, our proposed mechanisms do not need any information beyond the information already known by traditional job schedulers. Nor do they require extensive profiling of workloads to determine optimal schedules. Our mechanisms are based on dynamic resource partitioning. The OS level job scheduler needs to be slightly adapted in orde...

• Type: Conference
• Year: 2005
• Where: CASES
• Authors: Francisco J. Cazorla, Peter M. W. Knijnenburg, Rizos Sakellariou, Enrique Fernández, Alex Ramírez, Mateo Valero
• Keywords: CASES 2005, Hardware Resource, Job Scheduler, Resource Partitioning, System Software