Joseph Schuchart
Center for Information Services and High Performance Computing, TU Dresden, Germany
Volker Waurich
Chair of Construction Machines and Conveying Technology, TU Dresden, Germany
Martin Flehmig
Center for Information Services and High Performance Computing, TU Dresden, Germany
Marcus Walther
Center for Information Services and High Performance Computing, TU Dresden, Germany
Wolfgang E. Nagel
Center for Information Services and High Performance Computing, TU Dresden, Germany
Ines Gubsch
Chair of Construction Machines and Conveying Technology, TU Dresden, Germany
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http://dx.doi.org/10.3384/ecp15118265Published in: Proceedings of the 11th International Modelica Conference, Versailles, France, September 21-23, 2015
Linköping Electronic Conference Proceedings 118:28, p. 265-272
Published: 2015-09-18
ISBN: 978-91-7685-955-1
ISSN: 1650-3686 (print), 1650-3740 (online)
Large and highly-detailed Modelica models are frequently
modeled by utilizing repeated structures, which
is a repetition of various elements that are linked together
in an iterative manner. While the Modelica language
standard supports the representation of repeated structures,
it is still not clear how repeated structures can be
handled efficiently during model compilation. Instead of
preserving the compact notation from the model, all repeated
equations are flattened and all array variables are
expanded. This leads to unnecessary long compilation
times and higher memory consumption. Another aspect
that has been yet inadequately considered and is closely
connected to repeated structures is vectorization. The
vector units of modern CPUs can be engaged to perform
SIMD (Single Instruction, Multiple Data) operations, executing
the same instruction on multiple data points in
parallel. This reveals a high potential for faster simulations.
This paper discusses the advantages of utilizing
repeated structures for modeling in order to achieve
both faster compilation and simulation times. The potentials
of preserving for loops throughout compilation
are demonstrated using a basic implementation in the
OpenModelica Compiler. The effect on the simulation
time by enabling vectorization is demonstrated for an appropriate
model.
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