MIRA

Dongkook Park, Soumya Eachempati, Reetuparna Das, Asit K. Mishra, Yuan Xie, N. Vijaykrishnan, Chita R. Das
2008 SIGARCH Computer Architecture News  
Recently, Network-on-Chip (NoC) architectures have gained popularity to address the interconnect delay problem for designing CMP / multi-core / SoC systems in deep sub-micron technology. However, almost all prior studies have focused on 2D NoC designs. Since three dimensional (3D) integration has emerged to mitigate the interconnect delay problem, exploring the NoC design space in 3D can provide ample opportunities to design high performance and energy-efficient NoC architectures. In this
more » ... we propose a 3D stacked NoC router architecture, called MIRA, which unlike the 3D routers in previous works, is stacked into multiple layers and optimized to reduce the overall area requirements and power consumption. We discuss the design details of a four-layer 3D NoC and its enhanced version with additional express channels, and compare them against a (6×6) 2D design and a baseline 3D design. All the designs are evaluated using a cycle-accurate 3D NoC simulator, and integrated with the Orion power model for performance and power analysis. The simulation results with synthetic and application traces demonstrate that the proposed multi-layered NoC routers can outperform the 2D and naïve 3D designs in terms of performance and power. It can achieve up to 42% reduction in power consumption and up to 51% improvement in average latency with synthetic workloads. With real workloads, these benefits are around 67% and 38%, respectively. into multiple layers, have appeared recently [16] . However, 3D stacking may result in temperature hotspots due to increased power density. Thus, any 3D design should consider the thermal issue in addition to other design parameters. In this paper, we investigate various architectural alternatives for designing a high performance, energyefficient, and 3D stacked NoC router, called MIRA. The design is based on the concept of dividing a traditional 2D NoC router along with the rest of the on-chip communication fabric into multiple layers, with the objective of exploiting the benefits of the 3D technology in enhancing the design of the router micro-architecture for better performance and power conservation. Our multi-layer NoC design is primarily motivated by the observed communication patterns in a Non-Uniform Cache Architecture (NUCA)-style CMP [44, 45] . The NoC in a NUCA architecture supports communication ------------------------------*
doi:10.1145/1394608.1382143 fatcat:i6pxabrnz5eklhykeijbknhsfi