forked from lijiext/lammps
54 lines
1.5 KiB
Plaintext
54 lines
1.5 KiB
Plaintext
"Higher level section"_Speed.html - "LAMMPS WWW Site"_lws - "LAMMPS
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Documentation"_ld - "LAMMPS Commands"_lc :c
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:link(lws,http://lammps.sandia.gov)
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:link(ld,Manual.html)
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:link(lc,Commands_all.html)
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:line
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OPT package :h3
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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 "Build extras"_Build_extras.html#opt doc page for instructions.
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[Run with the OPT package from the command line:]
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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 :pre
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Use the "-sf opt" "command-line switch"_Run_options.html, 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 "suffix opt"_suffix.html 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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pair_style lj/cut/opt 2.5 :pre
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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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None.
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