Hungarian algorithm based virtualization to maintain application timing similarity for defect-tolerant NoC

Homogeneous manycore processors are emerging in broad application areas, including those with timing requirements, such as real-time and embedded applications. Typically, these processors employ Network-on-Chip (NoC) as the communication infrastructure and core-level redundancy is often used as an effective approach to improve the yield of manycore chips. For a given application's task graph and a task to core mapping strategy, the traffic pattern on the NoC is known a priori. However, when defective cores are replaced by redundant ones, the NoC topology changes. As a result, a fine-tuned program based on timing parameters given by one topology may not meet the expected timing behavior under the new one. To address this issue, a timing similarity metric is introduced to evaluate timing resemblances between different NoC topologies. Based on this metric, a Hungarian method based algorithm is developed to reconfigure a defect-tolerant manycore platform and form a unified application specific virtual core topology of which the timing variations caused by such reconfiguration are minimized. Our case studies indicate that the proposed metric is able to accurately measure the timing differences between different NoC topologies. The standard deviation between the calculated difference using the metric and the difference obtained through simulation is less than 6.58%. Our case studies also indicate that the developed Hungarian method based algorithm using the metric performs close to the optimal solution in comparison to random defect-redundant core assignments.

[1]  Qiang Xu,et al.  On Topology Reconfiguration for Defect-Tolerant NoC-Based Homogeneous Manycore Systems , 2009, IEEE Transactions on Very Large Scale Integration (VLSI) Systems.

[2]  Radu Marculescu,et al.  Energy-aware mapping for tile-based NoC architectures under performance constraints , 2003, ASP-DAC '03.

[3]  Srinivasan Murali,et al.  Bandwidth-constrained mapping of cores onto NoC architectures , 2004, Proceedings Design, Automation and Test in Europe Conference and Exhibition.

[4]  Xiaowei Li,et al.  Performance-asymmetry-aware topology virtualization for defect-tolerant NoC-based many-core processors , 2010, 2010 Design, Automation & Test in Europe Conference & Exhibition (DATE 2010).

[5]  Harold W. Kuhn,et al.  The Hungarian method for the assignment problem , 1955, 50 Years of Integer Programming.

[6]  Seong-Jun Oh,et al.  Distributed SC-FDMA Resource Allocation Algorithm Based on the Hungarian Method , 2009, 2009 IEEE 70th Vehicular Technology Conference Fall.

[7]  Wayne H. Wolf,et al.  TGFF: task graphs for free , 1998, Proceedings of the Sixth International Workshop on Hardware/Software Codesign. (CODES/CASHE'98).

[8]  Irwin L. Kellner TURN DOWN THE HEAT , 1995 .

[9]  J. Munkres ALGORITHMS FOR THE ASSIGNMENT AND TRANSIORTATION tROBLEMS* , 1957 .

[10]  Narayanan Vijaykrishnan,et al.  Thermal-aware IP virtualization and placement for networks-on-chip architecture , 2004, IEEE International Conference on Computer Design: VLSI in Computers and Processors, 2004. ICCD 2004. Proceedings..

[11]  H. Kuhn The Hungarian method for the assignment problem , 1955 .

[12]  Qiang Xu,et al.  Defect Tolerance in Homogeneous Manycore Processors Using Core-Level Redundancy with Unified Topology , 2008, 2008 Design, Automation and Test in Europe.

[13]  José Duato,et al.  On the Potential of NoC Virtualization for Multicore Chips , 2008, 2008 International Conference on Complex, Intelligent and Software Intensive Systems.

[14]  I. Gungor,et al.  Fuzzy multiple criteria assignment problems for fusion: the case of Hungarian algorithm , 2000, Proceedings of the Third International Conference on Information Fusion.