Conference Paper

Coloured Petri Net Modelling of Task Scheduling on a Heterogeneous Computational Node

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This paper presents the development of a Coloured Petri Net model for a concurrent application running on a heterogeneous multi/manycore node. The used software runtime (StarPu) allows the expression of the application as a DAG (Directed Acyclic Graph) of tasks and the partition of the heterogeneous hardware in worker units. The CPN modelling allows the rapid evaluation of the suitability of the implemented scheduling algorithms for a given problem and supports the process of new algorithms design and implementation. The scheduler models were validated through runs on the real architecture.

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... This is accomplished by numerical solving the system of partial differential equations describing the flow. As described in [1], [12], [13] the parallelisation for such application can be achieved through domain decomposition and an alternation of parallel independent computation steps on the sub-domains with communication steps. In the communication steps, border zones, called ghost zones, are transferred between neighbors to permit computation in the next step. ...
... A scheduler distributes the tasks as soon as their dependencies are solved to the available idle PU. We extends here our work presented in [12] with the part responsible for the interaction with the superior level. We used AMPI/Charm++ for the inter-node level [11]. ...
... The Snoopy framework [16] for Petri Net modeling and simulation was used. In contrast to the CPN Tools we used in [12], [13], this framework has an active development, support for remote simulation and interactive steering [17] and an ecosystem of tools for formal analysis (Charlie [18]) and verification (Marcie [19]). From the rich hierarchy of classes provided by Snoopy the XSPN c class ( c olored eXtended Stochastic Petri Net) was used. ...
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