6,089 research outputs found
A Compilation Flow for Parametric Dataflow: Programming Model, Scheduling, and Application to Heterogeneous MPSoC
International audienceEfficient programming of signal processing applications on embedded systems is a complex problem. High level models such as Synchronous dataflow (SDF) have been privileged candidates for dealing with this complexity. These models permit to express inherent application parallelism, as well as analysis for both verification and optimization. Parametric dataflow models aim at providing sufficient dynamicity to model new applications, while at the same time maintaining the high level of analyzability needed for efficient real life implementations. This paper presents a new compilation flow that targets parametric dataflows. Built on the LLVM compiler infrastructure, it offers an actor based C++ programming model to describe parametric graphs, a compilation front-end providing graph analysis features, and a retargetable back-end to map the application on real hardware. This paper gives an overview of this flow, with a specific focus on scheduling. The crucial gap between dataflow models and real hardware on which actor firing is not atomic, as well as the consequences on FIFOs sizing and execution pipelining are taken into account.The experimental results illustrate our compilation flow applied to compilation of 3GPP LTE-Advanced demodulation on a heterogeneous MPSoC with distributed scheduling features. This achieves performances similar to time-consuming hand made optimizations
Impact of technological synchronicity on prospects for CETI
For over 50 years, astronomers have searched the skies for evidence of
electromagnetic signals from extraterrestrial civilizations that have reached
or surpassed our level of technological development. Although often overlooked
or given as granted, the parallel use of an equivalent communication technology
is a necessary prerequisite for establishing contact in both leakage and
deliberate messaging strategies. Civilization advancements, especially
accelerating change and exponential growth, lessen the perspective for a
simultaneous technological status of civilizations thus putting hard
constraints on the likelihood of a dialogue. In this paper we consider the
mathematical probability of technological synchronicity of our own and a number
of other hypothetical extraterrestrial civilizations and explore the most
likely scenarios for their concurrency. If SETI projects rely on a fortuitous
detection of leaked interstellar signals (so called "eavesdropping") then
without any prior assumptions N \geq 138-4991 Earth-like civilizations have to
exist at this moment in the Galaxy for the technological usage synchronicity
probability p \geq 0.95 in the next 20 years. We also show that since the
emergence of complex life, coherent with the hypothesis of the Galactic
habitable zone, N \geq 1497 extraterrestrial civilizations had to be created in
the Galaxy in order to achieve the same estimated probability in the
technological possession synchronicity which corresponds to the deliberate
signaling scenario.Comment: 15 pages, 7 figures, 1 table, accepted for publication in the
International Journal of Astrobiolog
Formal Modeling and Verification of GALS Systems Using GRL and CADP
The GALS (Globally Asynchronous, Locally Synchronous) paradigm is a prevalent approach to design distributed synchronous subsystems that communicate with each other asynchronously. The design of GALS systems is tedious and error-prone due to the complexity of architectures and high synchronous and asynchronous concurrency involved. This paper proposes a model-based approach to formally verify such systems. Specifications are written in GRL (GALS Representation Language), dedicated to model GALS systems with homogeneous syntax and formal semantics. We present a translation from GRL to LNT, a value-passing process algebra with imperative flavour. The translation is automated by means of the GRL2LNT tool, making possible the analysis of GRL specifications using the CADP toolbox. We illustrate our approach with an access management system for smart parking based on distributed software systems embedded in programmable logic controllers
Formal Modeling and Verification of GALS Systems Using GRL and CADP
The GALS (Globally Asynchronous, Locally Synchronous) paradigm is a prevalent approach to design distributed synchronous subsystems that communicate with each other asynchronously. The design of GALS systems is tedious and error-prone due to the complexity of architectures and high synchronous and asynchronous concurrency involved. This paper proposes a model-based approach to formally verify such systems. Specifications are written in GRL (GALS Representation Language), dedicated to model GALS systems with homogeneous syntax and formal semantics. We present a translation from GRL to LNT, a value-passing process algebra with imperative flavour. The translation is automated by means of the GRL2LNT tool, making possible the analysis of GRL specifications using the CADP toolbox. We illustrate our approach with an access management system for smart parking based on distributed software systems embedded in programmable logic controllers
- …