<li class="toctree-l2"><a class="reference internal" href="Section_accelerate.html#comparison-of-various-accelerator-packages">5.4. Comparison of various accelerator packages</a></li>
<p><strong>Building LAMMPS with the OPT package:</strong></p>
<p>The lines above illustrate how to build LAMMPS with the OPT package in
two steps, using the “make” command. Or how to do it with one command
via the src/Make.py script, described in <a class="reference internal" href="Section_start.html#start-4"><span class="std std-ref">Section 2.4</span></a> of the manual. Type “Make.py -h” for
help.</p>
<p>Note that if you use an Intel compiler to build with the OPT package,
the CCFLAGS setting in your Makefile.machine must include “-restrict”.
The Make.py command will add this automatically.</p>
<p><strong>Run with the OPT package from the command line:</strong></p>
<p>As in the lines above, use the “-sf opt” <a class="reference internal" href="Section_start.html#start-7"><span class="std std-ref">command-line switch</span></a>, which will automatically append
“opt” to styles that support it.</p>
<p><strong>Or run with the OPT package by editing an input script:</strong></p>
<p>Use the <a class="reference internal" href="suffix.html"><span class="doc">suffix opt</span></a> command, or you can explicitly add an
“opt” suffix to individual styles in your input script, e.g.</p>
<pre class="literal-block">
pair_style lj/cut/opt 2.5
</pre>
<p><strong>Speed-ups to expect:</strong></p>
<p>You should see a reduction in the “Pair time” value printed at the end
of a run. On most machines for reasonable problem sizes, it will be a
5 to 20% savings.</p>
<p><strong>Guidelines for best performance:</strong></p>
<p>Just try out an OPT pair style to see how it performs.</p>
Built with <a href="http://sphinx-doc.org/">Sphinx</a> using a <a href="https://github.com/snide/sphinx_rtd_theme">theme</a> provided by <a href="https://readthedocs.org">Read the Docs</a>.