Recent advances in GPU-based manycore accelerators provide the opportunity to efficiently process large-scale graphs on chip. However, real world graphs have a diverse range of topology and connectivity patterns (e.g., degree distributions) that make the design of input-agnostic hardware architectures a challenge. Network-on-Chip (NoC)- based architectures provide a way to overcome this challenge as the architectural topology can be used to approximately model the expected traffic patterns that emerge from graph application workloads. In this paper, we first study the mix of long- and short-range traffic patterns generated on-chip using graph workloads, and subsequently use the findings to adapt the design of an optimal NoC-based architecture. In particular, by leveraging emerging three-dimensional (3D) integration technology, we propose design of a small-world NoC (SWNoC)- enabled manycore GPU architecture, where the placement of the links connecting the streaming multiprocessors (SM) and the memory controllers (MC) follow a power-law distribution. The proposed 3D manycore GPU architecture outperforms the traditional planar (2D) counterparts in both performance and energy consumption. Moreover, by adopting a joint performance-thermal optimization strategy, we address the thermal concerns in a 3D design without noticeably compromising the achievable performance. The 3D integration technology is also leveraged to incorporate Near Data Processing (NDP) to complement the performance benefits introduced by the SWNoC architecture. As graph applications are inherently memory intensive, off-chip data movement gives rise to latency and energy overheads in the presence of external DRAM. In conventional GPU architectures, as the main memory layer is not integrated with the logic, off-chip data movement negatively impacts overall performance and energy consumption. We demonstrate that NDP significantly reduces the overheads associated with such frequent and irregular memory accesses in graph-based applications. The proposed SWNoC-enabled NDP framework that integrates 3D memory (like Micron's HMC) with a massive number of GPU cores achieves 29.5% performance improvement and 30.03% less energy consumption on average compared to a conventional planar Mesh-based design with external DRAM.
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Protecting Real-Time GPU Kernels on Integrated CPU-GPU SoC Platforms
Integrated CPU-GPU architecture provides excellent acceleration capabilities for data parallel applications on embedded platforms while meeting the size, weight and power (SWaP) requirements. However, sharing of main memory between CPU applications and GPU kernels can severely affect the execution of GPU kernels and diminish the performance gain provided by GPU. For example, in the NVIDIA Jetson TX2 platform, an integrated CPU-GPU architecture, we observed that, in the worst case, the GPU kernels can suffer as much as 3X slowdown in the presence of co-running memory intensive CPU applications. In this paper, we propose a software mechanism, which we call BWLOCK++, to protect the performance of GPU kernels from co-scheduled memory intensive CPU applications.
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- Award ID(s):
- 1815959
- NSF-PAR ID:
- 10097572
- Date Published:
- Journal Name:
- Leibniz international proceedings in informatics
- Volume:
- 106
- ISSN:
- 1868-8969
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.4230/LIPIcs.ECRTS.2018.19
