Improving the Configuration of the Predictable ACDC Data Cache for Real-Time Systems

[EN] In real-time systems, analyzing the worst-case execution time (WCET) of a task in the presenceof data caches is hard. The ACDC is a data cache that provides predictability, facilitating WCET analysis.It works by granting data cache replacement permission to speci_c load/store instructions. None...

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Detalles Bibliográficos
Autores: Segarra, Juan, Martí-Campoy, Antonio|||0000-0002-6009-8703
Tipo de recurso: artículo
Fecha de publicación:2022
País:España
Institución:Universitat Politècnica de València (UPV)
Repositorio:RiuNet. Repositorio Institucional de la Universitat Politécnica de Valéncia
Idioma:inglés
OAI Identifier:oai:riunet.upv.es:10251/194306
Acceso en línea:https://riunet.upv.es/handle/10251/194306
Access Level:acceso abierto
Palabra clave:ACDC
WCET
Data cache
Real-time
Genetic algorithms
Static analysis
ARQUITECTURA Y TECNOLOGIA DE COMPUTADORES
Descripción
Sumario:[EN] In real-time systems, analyzing the worst-case execution time (WCET) of a task in the presenceof data caches is hard. The ACDC is a data cache that provides predictability, facilitating WCET analysis.It works by granting data cache replacement permission to speci_c load/store instructions. Nonetheless,knowing how to select these instructions to minimize the WCET, i.e., con_guring the ACDC, is not trivial. In this paper, we propose four new methods to con_gure the ACDC, and compare them with existingmethods. Unlike those in previous studies, our proposed methods provide speci_c ACDC con_gurationsfor the different phases of a given task, instead of a single ACDC con_guration per task. We evaluate theWCET bounds obtained when using different ACDC con_guration methods on the TACLeBench benchmark suite. Our results show that the most complex benchmarks work better with multiple-content con_gurations,which indicates that realistic tasks may also bene_t from this kind of con_guration. The methods proposedin this study improve the WCET in more than 60% of cases, with an average WCET improvement of nearly5% and up to 50% in some cases.