Topology Virtualization for Throughput Maximization on Many-Core Platforms

As transistor´s feature size continues to scale down into the deep sub-micron domain, IC chip performance variation caused by manufacturing process becomes un-negligible and can cause significant discrepancies between an application´s nominal design and its actual realization on individual manycore platforms. In this paper, we study the problem on how to reduce the total schedule length of a task graph when realizing its nominal design on individual Network-on-Chip(NoC) based many-core platform with faulty cores. Different from traditional approaches to re-define the mapping/scheduling decisions in the nominal design, our methods judiciously mirror the physical architecture of each individual platform to the logical platform, based on which the nominal design is conducted. To facilitate the phyical/logic architecture virtualization, we develop a performance metric based on the opportunity cost, a concept borrowed from the economics field. Three virtualization heuristics are presented in this paper. Our experimental results show that the proposed approach can achieve up to 30% with an average 15% performance improvement by taking advantage of the heterogeneity of each individual platform.