Performance analysis of FlexRay-based systems using real-time calculus, revisited

The FlexRay protocol [4] is likely to be the de facto standard for automotive communication systems. Hence, there is a need to provide hard performance guarantees on properties like worst case response times of messages, their buffer re-quirements, end-to-end latency (for example, from sensor to actuator), etc., for FlexRay based systems. The paper [11] provides an analysis for finding worst case response times of the messages transmitted on the FlexRay bus, but the analysis is done using ILP formulation and is thus compu-tationally expensive. The paper [5] models the FlexRay in the analytic framework of Real-Time Calculus [12, 3] and is compositional as well as scalable. In this paper, we show that the analysis of [5] may lead to results that are over op-timistic; in particular, we show that obtaining the “upper service curves ” is not trivial and does not follow the reason-ing of the “lower service curves ” which the authors obtain. We also provide tighter “lower service curves ” than that of [5]. Finally we show that our model allows the messages to be of variable size which is not the case with [5]. Categories and Subject Descriptors C.3 [Special-purpose and application-based systems]: Real-time and embedded systems; C.4 [Performance of systems]: Design studies and modeling technique

Performance analysis of FlexRay-based systems using real-time calculus, revisited

The FlexRay protocol [4] is likely to be the de facto standard for automotive communication systems. Hence, there is a need to provide hard performance guarantees on properties like worst case response times of messages, their buffer re-quirements, end-to-end latency (for example, from sensor to actuator), etc., for FlexRay based systems. The paper [11] provides an analysis for finding worst case response times of the messages transmitted on the FlexRay bus, but the analysis is done using ILP formulation and is thus compu-tationally expensive. The paper [5] models the FlexRay in the analytic framework of Real-Time Calculus [12, 3] and is compositional as well as scalable. In this paper, we show that the analysis of [5] may lead to results that are over op-timistic; in particular, we show that obtaining the “upper service curves ” is not trivial and does not follow the reason-ing of the “lower service curves ” which the authors obtain. We also provide tighter “lower service curves ” than that of [5]. Finally we show that our model allows the messages to be of variable size which is not the case with [5]. Categories and Subject Descriptors C.3 [Special-purpose and application-based systems]: Real-time and embedded systems; C.4 [Performance of systems]: Design studies and modeling technique

PRO3D, Programming for Future 3D Manycore Architectures: Project\u2019s Interim StatusFormal Methods for Components and Objects

PRO3D tackles two important 3D technologies, that are Through Silicon Via (TSV) and liquid cooling, and investigates their consequences on stacked architectures and entire software development. In particular, memory hierarchies are being revisited and the thermal impact of software on the 3D stack is explored. As a key result, a software design flow based on the rigorous assembly of software components and monitoring of the thermal integrity of the 3D stack has been developed. After 30 months of research, PRO3D proposes a complete tool-chain for 3D manycore, that integrates state-of-the-art tools ranging from system-level formal specification and 3D exploration, to actual programming and runtime control on the 3D system. Current efforts are directed towards extensive experiments on an industrial embedded manycore platfor

PRO3D, Programming for Future 3D Manycore Architectures: Project Interim Status

International audiencePRO3D tackles two important 3D technologies, that are ThroughSilicon Via (TSV) and liquid cooling, and investigates their consequenceson stacked architectures and entire software development. Inparticular, memory hierarchies are being revisited and the thermal impactof software on the 3D stack is explored. As a key result, a software design flow based on the rigorous assembly of software components andmonitoring of the thermal integrity of the 3D stack has been developed.After 30 months of research, PRO3D proposes a complete tool-chain for3D manycore, that integrates state-of-the-art tools ranging from system-levelformal specification and 3D exploration, to actual programming andruntime control on the 3D system. Current efforts are directed towardsextensive experiments on an industrial embedded manycore platform