Towards an efficient cost function equation for DDR SDRAM interference analysis on heterogeneous MPSoCs

Alfonso Mascareñas González (1) , Jean-Baptiste Chaudron (1) , Frédéric Boniol (2) , Youcef Bouchebaba (2) , Jean-Loup Bussenot (2)

1 DISC - Département d'Ingénierie des Systèmes Complexes
2 DTIS, ONERA, Université de Toulouse [Toulouse]

Real-time applications must finish their execution within an imposed deadline to function correctly. DDR memory interference on multicore platforms can make tasks overpass their respective deadline, leading to critical errors. Bandwidth regulators and SDRAM bank partitioning are examples of techniques used to mitigate or avoid this interference type. Another possibility is to optimally place tasks and memory on the platform, i.e., task/memory mapping optimization. The algorithms used for finding optimal mapping solutions work using a cost function that indicates the fitness of the found solution. In this work, we propose a DDR SDRAM cost function that estimates the worst-case execution time for a giving map, and hence, implementable in an optimization algorithm. Our cost function considers the DDR memory device operation, the SoC manufacturer memory controller, the heterogeneity of the platform and the characteristics of the tasks to map. The cost function is evaluated by measuring directly the interference from the heterogeneous MPSoCs Keystone II and Sitara AM5728 by Texas Instruments.

Keywords: Heterogeneous multicore platforms; Cost function; Memory interference; DDR SDRAM

Domains: Other

Alfonso Mascareñas González, Jean-Baptiste Chaudron, Frédéric Boniol, Youcef Bouchebaba, Jean-Loup Bussenot. Towards an efficient cost function equation for DDR SDRAM interference analysis on heterogeneous MPSoCs. 2022 IEEE/ACM 26th International Symposium on Distributed Simulation and Real Time Applications (DS-RT), Sep 2022, Alès, France. pp.29-38. ⟨hal-03940685⟩