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<CENTER><A HREF = "http://lammps.sandia.gov">LAMMPS WWW Site</A> - <A HREF = "Manual.html">LAMMPS Documentation</A> - <A HREF = "Section_commands.html#comm">LAMMPS Commands</A>
</CENTER>
<HR>
<H3>accelerator command
</H3>
<P><B>Syntax:</B>
</P>
<PRE>accelerator style args
</PRE>
<UL><LI>style = <I>off</I> or <I>on</I> or <I>cuda</I>
<LI>args = 0 or more args specific to the style
<PRE> <I>off</I> args = none
<I>on</I> args = none
<I>cuda</I> args = to be determined
</PRE>
</UL>
<P><B>Examples:</B>
</P>
<PRE>accelerator off
accelerator on
accelerator cuda blah
</PRE>
<P><B>Description:</B>
</P>
<P>Alter settings for use of accelerated versions of various styles.
LAMMPS can be built with optional packages which provide accelerated
versions of specific <A HREF = "atom_style.html">atom</A>, <A HREF = "pair_style.html">pair</A>,
<A HREF = "fix.html">fix</A>, <A HREF = "compute.html">compute</A>, and <A HREF = "run_style.html">integrate</A>
styles.
</P>
<P>These are the relevant packages:
</P>
<UL><LI>OPT = a handful of pair styles, cache-optimized for faster CPU performance
<LI>GPU = a handful of pair styles and the PPPM kspace_style, optimized to run on one or more GPUs or multicore CPU/GPU nodes
<LI>USER-CUDA = a collection of atom, pair, fix, compute, and intergrate styles, optimized to run on one or more NVIDIA GPUs
</UL>
<P>See <A HREF = "Section_start.html#2_3">this section</A> of the manual for
instructions on how to build LAMMPS with any of these packages.
</P>
<P>These styles can be specified explicitly in your input script,
e.g. <A HREF = "pair_lj.html">pair_style lj/cut/gpu</A>. If the -accelerator
command-line switch is used, you do not need to modify your input
script, as discussed in <A HREF = "Section_start.html#2_6">this section</A> of the
manual. The command-line suffix (opt,gpu,cuda) is automatically
appended when the style is created for atom, pair, fix, compute, and
integrate styles. If an accelerated version does not exist, the
standard version is created.
</P>
<P>If the -accelerator command-line switch is used, you may wish to
disable it for one or more input script commands, so that the standard
version of the style is used instead of the accelerated one. This can
be useful for performance testing or debugging.
</P>
<P>The <I>off</I> style allows you to do this. The effect of the -accelerator
command-line switch is effectively turned off until another
accelerator command is used with the <I>on</I> style.
</P>
<P>The <I>cuda</I> style invokes options associated with the use of the
USER-CUDA package. These will be described when the USER-CUDA package
is released with LAMMPS.
</P>
<P><B>Restrictions:</B>
</P>
<P>This cuda style can only be invoked if LAMMPS was built with the
USER-CUDA package. See the <A HREF = "Section_start.html#2_3">Making LAMMPS</A>
section for more info.
</P>
<P>Obviously, you must have GPU hardware and associated software to build
and use LAMMPS with either the GPU or USER_CUDA packages.
</P>
<P><B>Related commands:</B>
</P>
<P><A HREF = "fix_gpu.html">fix gpu</A>
</P>
<P><B>Default:</B> none
</P>
</HTML>
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