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+Performance
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+===========
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+
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+For performance benchmarks, it is desirable to achieve as high performance as feasible with PythonPDEVS.
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+By default, PythonPDEVS offers a lot of features, most of which have a (very) negative impact on actual performance.
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+While this might not be too noticable on small or medium-sized models, huge models will become unbearably slow in the default configuration.
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+
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+There are two proposed tweaks, which on average increase performance by a factor 12.
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+
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+Minimal Simulation Kernel
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+-------------------------
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+
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+Using the minimal simulation kernel disables most performance-affecting features, thus significantly increasing performance.
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+Note, however, that most of the advertised features will simply not work in this configuration.
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+This option is preferred for a fair comparison with other tools, as the PythonPDEVS defaults were chosen for usability, rather than performance.
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+
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+To use the minimal simulation kernel, simply replace all imports of PythonPDEVS to include the file ``pypdevs.minimal``.
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+This includes the ``AtomicDEVS``, ``CoupledDEVS``, and ``Simulator`` classes, and can thus be used instead of the ``pypdevs.DEVS`` and ``pypdevs.simulator`` files.
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+Both simulation kernels have the same interface, so switching can be done merely by changing the import statements.
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+When all features are desired, for example for debugging, the imports can easily be changed again to the full version of the PythonPDEVS simulation kernel.
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+
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+Use of PyPy
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+-----------
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+
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+Much of the performance related problems in PythonPDEVS are related to the Python interpreter itself.
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+We therefore recommend the use of PyPy as an alternative drop-in replacement for the default CPython implementation.
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+PyPy is the main development platform of PythonPDEVS as well.
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+
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+Note that at the time of writing, PyPy does not always behave well on Windows systems.
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+It works perfectly fine on Linux.
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