59 lines
1.4 KiB
ReStructuredText
59 lines
1.4 KiB
ReStructuredText
OPT package
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===========
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The OPT package was developed by James Fischer (High Performance
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Technologies), David Richie, and Vincent Natoli (Stone Ridge
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Technologies). It contains a handful of pair styles whose compute()
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methods were rewritten in C++ templated form to reduce the overhead
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due to if tests and other conditional code.
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**Required hardware/software:**
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None.
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**Building LAMMPS with the OPT package:**
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See the :ref:`Build extras <opt>` doc page for instructions.
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**Run with the OPT package from the command line:**
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.. parsed-literal::
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lmp_mpi -sf opt -in in.script # run in serial
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mpirun -np 4 lmp_mpi -sf opt -in in.script # run in parallel
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Use the "-sf opt" :doc:`command-line switch <Run_options>`, which will
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automatically append "opt" to styles that support it.
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**Or run with the OPT package by editing an input script:**
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Use the :doc:`suffix opt <suffix>` command, or you can explicitly add an
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"opt" suffix to individual styles in your input script, e.g.
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.. parsed-literal::
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pair_style lj/cut/opt 2.5
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**Speed-ups to expect:**
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You should see a reduction in the "Pair time" value printed at the end
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of a run. On most machines for reasonable problem sizes, it will be a
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5 to 20% savings.
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**Guidelines for best performance:**
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Just try out an OPT pair style to see how it performs.
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Restrictions
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""""""""""""
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None.
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.. _lws: http://lammps.sandia.gov
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.. _ld: Manual.html
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.. _lc: Commands_all.html
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