“WATS: Workload- Aware Task Scheduling in Asymmetric Multicore Architectures” - Dr. Zhiyi Huang (Senior Lecturer, University of Otago. New Zealand)
I Multicore World - 27-28 March 2012, Wellington, New Zealand
Abstract - Asymmetric Multi-Core (AMC) architectures have shown high performance as well as power efficiency. However, current parallel programming environments do not perform well on AMC due to their assumption that all cores are symmetric and provide equal performance. Their random task scheduling policies, such as task-stealing, can result in unbalanced workloads in AMC and severely degrade the performance of parallel applications. To balance the workloads of parallel applications in AMC, this presentation proposes a Workload-Aware Task Scheduling (WATS) scheme that adopts history-based task allocation and preference-based task-stealing. The history-based task allocation is based on a near-optimal, static task allocation using the historical statistics collected during the execution of a parallel application. The preference-based task-stealing, which steals tasks based on a preference list, can dynamically adjust the workloads in AMC if the task allocation is less optimal due to approximation in the history-based task allocation. Experimental results show that WATS can improve the performance of CPU-bound applications up to 82.7% compared with the random task scheduling policies.
Zhiyi Huang is a Senior Lecturer at the Department of Computer Science, University of Otago, Dunedin, New Zealand. He received his BSc degree in Computer Science from the National University of Defense Technology (NUDT) in China in 1986. He obtained his PhD degree in Computer Science in 1992 from the same university. He worked in industry from 1992 to 1996 while he was a Lecturer in Dept of Computer Science atBeijing Institute of Technology (BIT). Then he worked in the School of Computing and Information Technology at Griffith University as a Research Fellow from 1996 to 1998. He joined the Department of Computer Science at Otago in 1998. He had been a visiting professor at EPFL (Swiss Federal Institute of Technology Lausanne) and Tsinghua University in 2005, and a visiting scientist at MIT CSAIL in 2009.
His main interests are parallel/distributed computing, multi-core systems, green computing, cluster/grid/cloud computing, operating systems, wireless sensor networks, parallel algorithms, high-performance computing, virtualization, computer architectures, and computer networks. He had also done research on the ATM network and its applications, parallel logic programming, and neural networks.