Deterministic memory abstraction and supporting multicore system architecture
Files
Accepted manuscript
Date
2018-07-01
Authors
Farshchi, Farzad
Prathap, Kumar
Mancuso, Renato
Yun, Heechul
Version
Accepted manuscript
OA Version
Citation
Farzad Farshchi, Kumar Prathap, Renato Mancuso, Heechul Yun. 2018. "Deterministic Memory Abstraction and Supporting Multicore System Architecture." LIPIcs : Leibniz International Proceedings in Informatics, Volume 106, pp. 1 - 25. https://doi.org/10.4230/LIPIcs.ECRTS.2018.1
Abstract
Poor time predictability of multicore processors has been a long-standing challenge in the real-time systems community. In this paper, we make a case that a fundamental problem that prevents efficient and predictable real-time computing on multicore is the lack of a proper memory abstraction to express memory criticality, which cuts across various layers of the system: the application, OS, and hardware. We, therefore, propose a new holistic resource management approach driven by a new memory abstraction, which we call Deterministic Memory. The key characteristic of deterministic memory is that the platform-the OS and hardware-guarantees small and tightly bounded worst-case memory access timing. In contrast, we call the conventional memory abstraction as best-effort memory in which only highly pessimistic worst-case bounds can be achieved. We propose to utilize both abstractions to achieve high time predictability but without significantly sacrificing performance. We present deterministic memory-aware OS and architecture designs, including OS-level page allocator, hardware-level cache, and DRAM controller designs. We implement the proposed OS and architecture extensions on Linux and gem5 simulator. Our evaluation results, using a set of synthetic and real-world benchmarks, demonstrate the feasibility and effectiveness of our approach.