The field of scientific computing is based on modeling
various physical phenomena. A promising approach
to improve the quality of this modeling is to combine
highly specialized simulation tools and is already common
practice in fields like Computational Fluid Dynamics
(CFD). In short, important tasks are to couple
simulations which model relevant phenomena on a
different physical level, thus performing multiphysics
computations. Although several multiphysics tools are
publicly available, the implementations are typically
based on assumptions with respect to the field of application.
The available frameworks applied in the field of distributed
high-performance scientific computing usually
focus on the data parallel approach based on the Message Passing Interface (MPI).
Typically, a mesh datastructure representing the simulation
domain is distributed, thus the solution is locally
evaluated at the individual subdomains. This approach
is referred to as domain decomposition, and is reflected
by a data parallel approach. As such, the tasks to
be executed by the framework are typically processed in
sequence, whereas each plugin itself utilizes the MPI
to distribute the work among the compute units, for
example, to utilize an MPI-based linear solver.
Our free open source framework, ViennaX, does not restrict itself to a specifc execution
behavior, in fact its focus is on providing an extendible
set of different schedulers to not only support data
parallel approaches, but also serial and task parallel
implementations. In this context, serial execution refers
to the execution of the tasks on a shared-memory
machine, enabling sequential execution of tasks, however,
the plugins can indeed have parallelized implementations
based on, for example, OpenMP or CUDA.
Such an approach becomes more and more important,
due to the broad availability of multi-core CPUs by simultaneously
stagnating clock frequencies.
In contrast, task parallel approaches can be used
to parallelize data flow applications, for instance, wave
front or digital logic simulations.
Our goal is to not only provide the general scientific community with a domain independent
plugin execution framework, but also to apply ViennaX to the field of semiconductor device
simulation. Utilizing ViennaX not only allows us to implement flexible device simulations, due to the
reusable component approach, but also enables high-performance implementations,
because of the data and task parallelism support.
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