forked from lijiext/lammps
git-svn-id: svn://svn.icms.temple.edu/lammps-ro/trunk@12318 f3b2605a-c512-4ea7-a41b-209d697bcdaa
This commit is contained in:
sjplimp
parent
af7d84de2d
commit
b2f3ef52e4
|
|
@ -978,45 +978,52 @@ LAMMPS.
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|||
<P>The USER-INTEL package was developed by Mike Brown at Intel
|
||||
Corporation. It provides a capability to accelerate simulations by
|
||||
offloading neighbor list and non-bonded force calculations to Intel
|
||||
coprocessors. Additionally, it supports running simulations in
|
||||
single, mixed, or double precision with vectorization, even if a
|
||||
coprocessor is not present. The same C++ code is used for both cases.
|
||||
When offloading to a coprocessor, the routine is run twice, once with
|
||||
an offload flag.
|
||||
coprocessors (Xeon Phi). Additionally, it supports running
|
||||
simulations in single, mixed, or double precision with vectorization,
|
||||
even if a coprocessor is not present, i.e. on an Intel CPU. The same
|
||||
C++ code is used for both cases. When offloading to a coprocessor,
|
||||
the routine is run twice, once with an offload flag.
|
||||
</P>
|
||||
<P>The USER-INTEL package will work with the USER-OMP package. Specifying
|
||||
use of the Intel package implicitly includes the OMP package allowing
|
||||
it to be used for angle, bond, dihedral, and long-range
|
||||
electrostatics. Using the <A HREF = "suffix.html">suffix intel</A> command will use
|
||||
styles from the Intel package if available; otherwise it will use
|
||||
styles from the OMP package if available.
|
||||
<P>The USER-INTEL package can be used in tandem with the USER-OMP
|
||||
package. This is useful when a USER-INTEL pair style is used, so that
|
||||
other styles not supported by the USER-INTEL package, e.g. for bond,
|
||||
angle, dihedral, improper, and long-range electrostatics can be run
|
||||
with the USER-OMP package versions. If you have built LAMMPS with
|
||||
both the USER-INTEL and USER-OMP packages, then this mode of operation
|
||||
is made easier, because the "-suffix intel" <A HREF = "Section_start.html#start_7">command-line
|
||||
switch</A> and the the <A HREF = "suffix.html">suffix
|
||||
intel</A> command will both set a second-choice suffix to
|
||||
"omp" so that styles from the USER-OMP package will be used if
|
||||
available.
|
||||
</P>
|
||||
<P><B>Building LAMMPS with the USER-INTEL package:</B>
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||||
</P>
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||||
<P>The procedure for building LAMMPS with the USER-INTEL package is
|
||||
simple. You have to edit your machine specific makefile to add the
|
||||
flags to enable OpenMP support (<I>-openmp</I>) to both the CCFLAGS and
|
||||
LINKFLAGS variables. You also need to add -restrict to CCFLAGS. If
|
||||
you are compiling on the same architecture that will be used for the
|
||||
runs, adding the flag <I>-xHost</I> will enable vectorization with the
|
||||
Intel compiler. In order to build with support for an Intel
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||||
LINKFLAGS variables. You also need to add -DLAMMPS_MEMALIGN=64 and
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-restrict to CCFLAGS.
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||||
</P>
|
||||
<P>If you are compiling on the same architecture that will be used for
|
||||
the runs, adding the flag <I>-xHost</I> will enable vectorization with the
|
||||
Intel compiler. In order to build with support for an Intel
|
||||
coprocessor, the flag <I>-offload</I> should be added to the LINKFLAGS line
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and the flag <I>-DLMP_INTEL_OFFLOAD</I> should be added to the CCFLAGS
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||||
line.
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</P>
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<P>The files src/MAKE/Makefile.intel and src/MAKE/Makefile.intel_offload
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are provided with options that perform well with the Intel
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compiler. The latter Makefile has support for offload to coprocessors
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||||
and the former does not.
|
||||
are included in the src/MAKE directory with options that perform well
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with the Intel compiler. The latter Makefile has support for offload
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||||
to coprocessors and the former does not.
|
||||
</P>
|
||||
<P>It is recommended that Intel Compiler 2013 SP1 update 1 be used for
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||||
compiling. Newer versions have some performance issues that are being
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||||
addressed. If using Intel MPI, version 5 or higher is recommended.
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||||
</P>
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||||
<P>The rest of the compilation is the same as for any other package that
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has no additional library dependencies:
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has no additional library dependencies, e.g.
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</P>
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<PRE>make yes-user-omp yes-user-intel
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<PRE>make yes-user-intel yes-user-omp
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make machine
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</PRE>
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<P><B>Running an input script:</B>
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|
@ -1032,94 +1039,97 @@ commands, and is independent of the Intel package.
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<P>Input script requirements to run using pair styles with a <I>intel</I>
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suffix are as follows:
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</P>
|
||||
<P>To invoke specific styles from the Intel package, either append
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<P>To invoke specific styles from the UESR-INTEL package, either append
|
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"intel" to the style name (e.g. pair_style lj/cut/intel), or use the
|
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<A HREF = "Section_start.html#start_7">-suffix command-line switch</A>, or use the
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||||
<A HREF = "suffix.html">suffix</A> command in the input script.
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</P>
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<P>Unless the <A HREF = "Section_start.html#start_7">-suffix intel command-line
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switch</A> is used, the <A HREF = "package.html">package
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switch</A> is used, a <A HREF = "package.html">package
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intel</A> command must be used near the beginning of the
|
||||
script. The default precision mode for the Intel package is <I>mixed</I>,
|
||||
meaning that accumulation is performed in double precision and other
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||||
calculations are performed in single precision. In order to use all
|
||||
single or all double precision, the "package intel" line must be used
|
||||
in the input script with a "single" or "double" keyword specified.
|
||||
input script. The default precision mode for the USER-INTEL package
|
||||
is <I>mixed</I>, meaning that accumulation is performed in double precision
|
||||
and other calculations are performed in single precision. In order to
|
||||
use all single or all double precision, the <A HREF = "package.html">package
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intel</A> command must be used in the input script with a
|
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"single" or "double" keyword specified.
|
||||
</P>
|
||||
<P><B>Running with an Intel coprocessor:</B>
|
||||
</P>
|
||||
<P>The Intel package supports offload of a fraction of the work to Intel
|
||||
coprocessors. This is accomplished by setting a balance fraction on
|
||||
the <A HREF = "package.html">package intel</A> line. A balance of 0 runs all
|
||||
calculations on the CPU. A balance of 1 runs all calculations on the
|
||||
coprocessor. A balance of 0.5 runs half of the calculations on the
|
||||
coprocessor. Setting the balance to -1 will enable dynamic load
|
||||
balancing that continously adjusts the fraction of offloaded work
|
||||
throughout the simulation. This option is typically within 5 to 10
|
||||
percent of the optimal fixed balance. By default, using the suffix
|
||||
command or command-line switch will use offload to a coprocessor with
|
||||
the balance set to -1. If LAMMPS is built without offload support,
|
||||
this setting is ignored.
|
||||
<P>The USER-INTEL package supports offload of a fraction of the work to
|
||||
Intel coprocessors (Xeon Phi). This is accomplished by setting a
|
||||
balance fraction on the <A HREF = "package.html">package intel</A> command. A
|
||||
balance of 0 runs all calculations on the CPU. A balance of 1 runs
|
||||
all calculations on the coprocessor. A balance of 0.5 runs half of
|
||||
the calculations on the coprocessor. Setting the balance to -1 will
|
||||
enable dynamic load balancing that continously adjusts the fraction of
|
||||
offloaded work throughout the simulation. This option typically
|
||||
produces results within 5 to 10 percent of the optimal fixed balance.
|
||||
By default, using the <A HREF = "suffix.html">suffix</A> command or <A HREF = "Section_start.html#start_7">-suffix
|
||||
command-line switch</A> will use offload to a
|
||||
coprocessor with the balance set to -1. If LAMMPS is built without
|
||||
offload support, this setting is ignored.
|
||||
</P>
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||||
<P>If one is running short benchmark runs with dynamic load balancing,
|
||||
adding a short warm-up run (10-20 steps) will allow the load-balancer
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||||
to find a setting that will be carried over to additional runs.
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to find a setting that will carry over to additional runs.
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||||
</P>
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<P>The default for the <A HREF = "package.html">package intel</A> command is to have
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all of the MPI tasks on a given compute node use a single
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coprocessor. In general, running with a large number of MPI tasks on
|
||||
each node will perform best with offload. Each MPI task will
|
||||
all the MPI tasks on a given compute node use a single coprocessor
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||||
(Xeon Phi). In general, running with a large number of MPI tasks on
|
||||
each node will perform best with offload. Each MPI task will
|
||||
automatically get affinity to a subset of the hardware threads
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available on the coprocessor. For example, if your card has 61 cores,
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with 60 cores available for offload and 4 hardware threads per core,
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running with 24 MPI tasks per node will cause each MPI task to use a
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subset of 10 threads on the coprocessor. Fine tuning of the number of
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||||
threads to use per MPI task or the number of threads to use per core
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||||
can be accomplished with keywords to the <A HREF = "package.html">package intel</A>
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||||
command.
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available on the coprocessor. For example, if your card has 61 cores,
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||||
with 60 cores available for offload and 4 hardware threads per core
|
||||
(240 total threads), running with 24 MPI tasks per node will cause
|
||||
each MPI task to use a subset of 10 threads on the coprocessor. Fine
|
||||
tuning of the number of threads to use per MPI task or the number of
|
||||
threads to use per core can be accomplished with keywords to the
|
||||
<A HREF = "package.html">package intel</A> command.
|
||||
</P>
|
||||
<P>If LAMMPS is using offload to a coprocessor, a diagnostic line during
|
||||
the setup for a run is printed to the screen (not to log files)
|
||||
indicating that offload is being used and the number of coprocessor
|
||||
threads per MPI task. Additionally, an offload timing summary is
|
||||
printed at the end of each run. When using offload, the
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||||
<A HREF = "atom_modify.html">sort</A> frequency for atom data is changed to 1 such
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||||
that the data is sorted every neighbor build.
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||||
<P>If LAMMPS is using offload to a coprocessor (Xeon Phi), a diagnostic
|
||||
line during the setup for a run is printed to the screen (not to log
|
||||
files) indicating that offload is being used and the number of
|
||||
coprocessor threads per MPI task. Additionally, an offload timing
|
||||
summary is printed at the end of each run. When using offload, the
|
||||
<A HREF = "atom_modify.html">sort</A> frequency for atom data is changed to 1 so
|
||||
that the per-atom data is sorted every neighbor build.
|
||||
</P>
|
||||
<P>In order to use multiple coprocessors on each compute node, the
|
||||
<P>To use multiple coprocessors (Xeon Phis) on each compute node, the
|
||||
<I>offload_cards</I> keyword can be specified with the <A HREF = "package.html">package
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||||
intel</A> command to specify the number of coprocessors to
|
||||
use.
|
||||
</P>
|
||||
<P>For simulations involving long-range electrostatics or angle, bond,
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||||
and dihedral calculations, computation and data transfer to the
|
||||
<P>For simulations with long-range electrostatics or bond, angle,
|
||||
dihedral, improper calculations, computation and data transfer to the
|
||||
coprocessor will run concurrently with computations and MPI
|
||||
communications for these routines on the host. The Intel package has
|
||||
two modes for deciding which atoms will be handled by the coprocessor.
|
||||
The setting is controlled with the "offload_ghost" option. When set to
|
||||
0, ghost atoms (atoms at the borders between MPI tasks) are not
|
||||
offloaded to the card. This allows for overlap of MPI communication of
|
||||
forces with computation on the coprocessor when the
|
||||
<A HREF = "newton.html">newton</A> setting is "on". The default is dependent on the
|
||||
style being used, however, better performance might be achieving by
|
||||
communications for these routines on the host. The USER-INTEL package
|
||||
has two modes for deciding which atoms will be handled by the
|
||||
coprocessor. The setting is controlled with the "offload_ghost"
|
||||
option. When set to 0, ghost atoms (atoms at the borders between MPI
|
||||
tasks) are not offloaded to the card. This allows for overlap of MPI
|
||||
communication of forces with computation on the coprocessor when the
|
||||
<A HREF = "newton.html">newton</A> setting is "on". The default is dependent on the
|
||||
style being used, however, better performance might be achieved by
|
||||
setting this explictly.
|
||||
</P>
|
||||
<P>In order to control the number of OpenMP threads used on the host, the
|
||||
OMP_NUM_THREADS environment variable should be set. This variable will
|
||||
not influence the number of threads used on the coprocessor. Only the
|
||||
"package intel" command can be used to control thread counts on the
|
||||
coprocessor.
|
||||
<A HREF = "package.html">package intel</A> command can be used to control thread
|
||||
counts on the coprocessor.
|
||||
</P>
|
||||
<P><B>Restrictions:</B>
|
||||
</P>
|
||||
<P>When using offload, <A HREF = "pair_hybrid.html">hybrid</A> styles that require skip
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||||
lists for neighbor builds cannot be offloaded to the coprocessor.
|
||||
Using <A HREF = "pair_hybrid.html">hybrid/overlay</A> is allowed. Only one intel
|
||||
accelerated style may be used with hybrid styles. Exclusion lists are
|
||||
Using <A HREF = "pair_hybrid.html">hybrid/overlay</A> is allowed. Only one intel
|
||||
accelerated style may be used with hybrid styles. Exclusion lists are
|
||||
not currently supported with offload, however, the same effect can
|
||||
often be accomplished by setting cutoffs for excluded atom types to
|
||||
0. None of the pair styles in the USER-OMP package support the
|
||||
"inner", "middle", "outer" options for r-RESPA integration.
|
||||
often be accomplished by setting cutoffs for excluded atom types to 0.
|
||||
None of the pair styles in the USER-OMP package currently support the
|
||||
"inner", "middle", "outer" options for rRESPA integration via the
|
||||
<A HREF = "run_style.html">run_style respa</A> command.
|
||||
</P>
|
||||
<HR>
|
||||
|
||||
|
|
|
|||
|
|
@ -974,45 +974,52 @@ LAMMPS.
|
|||
The USER-INTEL package was developed by Mike Brown at Intel
|
||||
Corporation. It provides a capability to accelerate simulations by
|
||||
offloading neighbor list and non-bonded force calculations to Intel
|
||||
coprocessors. Additionally, it supports running simulations in
|
||||
single, mixed, or double precision with vectorization, even if a
|
||||
coprocessor is not present. The same C++ code is used for both cases.
|
||||
When offloading to a coprocessor, the routine is run twice, once with
|
||||
an offload flag.
|
||||
coprocessors (Xeon Phi). Additionally, it supports running
|
||||
simulations in single, mixed, or double precision with vectorization,
|
||||
even if a coprocessor is not present, i.e. on an Intel CPU. The same
|
||||
C++ code is used for both cases. When offloading to a coprocessor,
|
||||
the routine is run twice, once with an offload flag.
|
||||
|
||||
The USER-INTEL package will work with the USER-OMP package. Specifying
|
||||
use of the Intel package implicitly includes the OMP package allowing
|
||||
it to be used for angle, bond, dihedral, and long-range
|
||||
electrostatics. Using the "suffix intel"_suffix.html command will use
|
||||
styles from the Intel package if available; otherwise it will use
|
||||
styles from the OMP package if available.
|
||||
The USER-INTEL package can be used in tandem with the USER-OMP
|
||||
package. This is useful when a USER-INTEL pair style is used, so that
|
||||
other styles not supported by the USER-INTEL package, e.g. for bond,
|
||||
angle, dihedral, improper, and long-range electrostatics can be run
|
||||
with the USER-OMP package versions. If you have built LAMMPS with
|
||||
both the USER-INTEL and USER-OMP packages, then this mode of operation
|
||||
is made easier, because the "-suffix intel" "command-line
|
||||
switch"_Section_start.html#start_7 and the the "suffix
|
||||
intel"_suffix.html command will both set a second-choice suffix to
|
||||
"omp" so that styles from the USER-OMP package will be used if
|
||||
available.
|
||||
|
||||
[Building LAMMPS with the USER-INTEL package:]
|
||||
|
||||
The procedure for building LAMMPS with the USER-INTEL package is
|
||||
simple. You have to edit your machine specific makefile to add the
|
||||
flags to enable OpenMP support ({-openmp}) to both the CCFLAGS and
|
||||
LINKFLAGS variables. You also need to add -restrict to CCFLAGS. If
|
||||
you are compiling on the same architecture that will be used for the
|
||||
runs, adding the flag {-xHost} will enable vectorization with the
|
||||
Intel compiler. In order to build with support for an Intel
|
||||
LINKFLAGS variables. You also need to add -DLAMMPS_MEMALIGN=64 and
|
||||
-restrict to CCFLAGS.
|
||||
|
||||
If you are compiling on the same architecture that will be used for
|
||||
the runs, adding the flag {-xHost} will enable vectorization with the
|
||||
Intel compiler. In order to build with support for an Intel
|
||||
coprocessor, the flag {-offload} should be added to the LINKFLAGS line
|
||||
and the flag {-DLMP_INTEL_OFFLOAD} should be added to the CCFLAGS
|
||||
line.
|
||||
|
||||
The files src/MAKE/Makefile.intel and src/MAKE/Makefile.intel_offload
|
||||
are provided with options that perform well with the Intel
|
||||
compiler. The latter Makefile has support for offload to coprocessors
|
||||
and the former does not.
|
||||
are included in the src/MAKE directory with options that perform well
|
||||
with the Intel compiler. The latter Makefile has support for offload
|
||||
to coprocessors and the former does not.
|
||||
|
||||
It is recommended that Intel Compiler 2013 SP1 update 1 be used for
|
||||
compiling. Newer versions have some performance issues that are being
|
||||
addressed. If using Intel MPI, version 5 or higher is recommended.
|
||||
|
||||
The rest of the compilation is the same as for any other package that
|
||||
has no additional library dependencies:
|
||||
has no additional library dependencies, e.g.
|
||||
|
||||
make yes-user-omp yes-user-intel
|
||||
make yes-user-intel yes-user-omp
|
||||
make machine :pre
|
||||
|
||||
[Running an input script:]
|
||||
|
|
@ -1028,94 +1035,97 @@ commands, and is independent of the Intel package.
|
|||
Input script requirements to run using pair styles with a {intel}
|
||||
suffix are as follows:
|
||||
|
||||
To invoke specific styles from the Intel package, either append
|
||||
To invoke specific styles from the UESR-INTEL package, either append
|
||||
"intel" to the style name (e.g. pair_style lj/cut/intel), or use the
|
||||
"-suffix command-line switch"_Section_start.html#start_7, or use the
|
||||
"suffix"_suffix.html command in the input script.
|
||||
|
||||
Unless the "-suffix intel command-line
|
||||
switch"_Section_start.html#start_7 is used, the "package
|
||||
switch"_Section_start.html#start_7 is used, a "package
|
||||
intel"_package.html command must be used near the beginning of the
|
||||
script. The default precision mode for the Intel package is {mixed},
|
||||
meaning that accumulation is performed in double precision and other
|
||||
calculations are performed in single precision. In order to use all
|
||||
single or all double precision, the "package intel" line must be used
|
||||
in the input script with a "single" or "double" keyword specified.
|
||||
input script. The default precision mode for the USER-INTEL package
|
||||
is {mixed}, meaning that accumulation is performed in double precision
|
||||
and other calculations are performed in single precision. In order to
|
||||
use all single or all double precision, the "package
|
||||
intel"_package.html command must be used in the input script with a
|
||||
"single" or "double" keyword specified.
|
||||
|
||||
[Running with an Intel coprocessor:]
|
||||
|
||||
The Intel package supports offload of a fraction of the work to Intel
|
||||
coprocessors. This is accomplished by setting a balance fraction on
|
||||
the "package intel"_package.html line. A balance of 0 runs all
|
||||
calculations on the CPU. A balance of 1 runs all calculations on the
|
||||
coprocessor. A balance of 0.5 runs half of the calculations on the
|
||||
coprocessor. Setting the balance to -1 will enable dynamic load
|
||||
balancing that continously adjusts the fraction of offloaded work
|
||||
throughout the simulation. This option is typically within 5 to 10
|
||||
percent of the optimal fixed balance. By default, using the suffix
|
||||
command or command-line switch will use offload to a coprocessor with
|
||||
the balance set to -1. If LAMMPS is built without offload support,
|
||||
this setting is ignored.
|
||||
The USER-INTEL package supports offload of a fraction of the work to
|
||||
Intel coprocessors (Xeon Phi). This is accomplished by setting a
|
||||
balance fraction on the "package intel"_package.html command. A
|
||||
balance of 0 runs all calculations on the CPU. A balance of 1 runs
|
||||
all calculations on the coprocessor. A balance of 0.5 runs half of
|
||||
the calculations on the coprocessor. Setting the balance to -1 will
|
||||
enable dynamic load balancing that continously adjusts the fraction of
|
||||
offloaded work throughout the simulation. This option typically
|
||||
produces results within 5 to 10 percent of the optimal fixed balance.
|
||||
By default, using the "suffix"_suffix.html command or "-suffix
|
||||
command-line switch"_Section_start.html#start_7 will use offload to a
|
||||
coprocessor with the balance set to -1. If LAMMPS is built without
|
||||
offload support, this setting is ignored.
|
||||
|
||||
If one is running short benchmark runs with dynamic load balancing,
|
||||
adding a short warm-up run (10-20 steps) will allow the load-balancer
|
||||
to find a setting that will be carried over to additional runs.
|
||||
to find a setting that will carry over to additional runs.
|
||||
|
||||
The default for the "package intel"_package.html command is to have
|
||||
all of the MPI tasks on a given compute node use a single
|
||||
coprocessor. In general, running with a large number of MPI tasks on
|
||||
each node will perform best with offload. Each MPI task will
|
||||
all the MPI tasks on a given compute node use a single coprocessor
|
||||
(Xeon Phi). In general, running with a large number of MPI tasks on
|
||||
each node will perform best with offload. Each MPI task will
|
||||
automatically get affinity to a subset of the hardware threads
|
||||
available on the coprocessor. For example, if your card has 61 cores,
|
||||
with 60 cores available for offload and 4 hardware threads per core,
|
||||
running with 24 MPI tasks per node will cause each MPI task to use a
|
||||
subset of 10 threads on the coprocessor. Fine tuning of the number of
|
||||
threads to use per MPI task or the number of threads to use per core
|
||||
can be accomplished with keywords to the "package intel"_package.html
|
||||
command.
|
||||
available on the coprocessor. For example, if your card has 61 cores,
|
||||
with 60 cores available for offload and 4 hardware threads per core
|
||||
(240 total threads), running with 24 MPI tasks per node will cause
|
||||
each MPI task to use a subset of 10 threads on the coprocessor. Fine
|
||||
tuning of the number of threads to use per MPI task or the number of
|
||||
threads to use per core can be accomplished with keywords to the
|
||||
"package intel"_package.html command.
|
||||
|
||||
If LAMMPS is using offload to a coprocessor, a diagnostic line during
|
||||
the setup for a run is printed to the screen (not to log files)
|
||||
indicating that offload is being used and the number of coprocessor
|
||||
threads per MPI task. Additionally, an offload timing summary is
|
||||
printed at the end of each run. When using offload, the
|
||||
"sort"_atom_modify.html frequency for atom data is changed to 1 such
|
||||
that the data is sorted every neighbor build.
|
||||
If LAMMPS is using offload to a coprocessor (Xeon Phi), a diagnostic
|
||||
line during the setup for a run is printed to the screen (not to log
|
||||
files) indicating that offload is being used and the number of
|
||||
coprocessor threads per MPI task. Additionally, an offload timing
|
||||
summary is printed at the end of each run. When using offload, the
|
||||
"sort"_atom_modify.html frequency for atom data is changed to 1 so
|
||||
that the per-atom data is sorted every neighbor build.
|
||||
|
||||
In order to use multiple coprocessors on each compute node, the
|
||||
To use multiple coprocessors (Xeon Phis) on each compute node, the
|
||||
{offload_cards} keyword can be specified with the "package
|
||||
intel"_package.html command to specify the number of coprocessors to
|
||||
use.
|
||||
|
||||
For simulations involving long-range electrostatics or angle, bond,
|
||||
and dihedral calculations, computation and data transfer to the
|
||||
For simulations with long-range electrostatics or bond, angle,
|
||||
dihedral, improper calculations, computation and data transfer to the
|
||||
coprocessor will run concurrently with computations and MPI
|
||||
communications for these routines on the host. The Intel package has
|
||||
two modes for deciding which atoms will be handled by the coprocessor.
|
||||
The setting is controlled with the "offload_ghost" option. When set to
|
||||
0, ghost atoms (atoms at the borders between MPI tasks) are not
|
||||
offloaded to the card. This allows for overlap of MPI communication of
|
||||
forces with computation on the coprocessor when the
|
||||
"newton"_newton.html setting is "on". The default is dependent on the
|
||||
style being used, however, better performance might be achieving by
|
||||
communications for these routines on the host. The USER-INTEL package
|
||||
has two modes for deciding which atoms will be handled by the
|
||||
coprocessor. The setting is controlled with the "offload_ghost"
|
||||
option. When set to 0, ghost atoms (atoms at the borders between MPI
|
||||
tasks) are not offloaded to the card. This allows for overlap of MPI
|
||||
communication of forces with computation on the coprocessor when the
|
||||
"newton"_newton.html setting is "on". The default is dependent on the
|
||||
style being used, however, better performance might be achieved by
|
||||
setting this explictly.
|
||||
|
||||
In order to control the number of OpenMP threads used on the host, the
|
||||
OMP_NUM_THREADS environment variable should be set. This variable will
|
||||
not influence the number of threads used on the coprocessor. Only the
|
||||
"package intel" command can be used to control thread counts on the
|
||||
coprocessor.
|
||||
"package intel"_package.html command can be used to control thread
|
||||
counts on the coprocessor.
|
||||
|
||||
[Restrictions:]
|
||||
|
||||
When using offload, "hybrid"_pair_hybrid.html styles that require skip
|
||||
lists for neighbor builds cannot be offloaded to the coprocessor.
|
||||
Using "hybrid/overlay"_pair_hybrid.html is allowed. Only one intel
|
||||
accelerated style may be used with hybrid styles. Exclusion lists are
|
||||
Using "hybrid/overlay"_pair_hybrid.html is allowed. Only one intel
|
||||
accelerated style may be used with hybrid styles. Exclusion lists are
|
||||
not currently supported with offload, however, the same effect can
|
||||
often be accomplished by setting cutoffs for excluded atom types to
|
||||
0. None of the pair styles in the USER-OMP package support the
|
||||
"inner", "middle", "outer" options for r-RESPA integration.
|
||||
often be accomplished by setting cutoffs for excluded atom types to 0.
|
||||
None of the pair styles in the USER-OMP package currently support the
|
||||
"inner", "middle", "outer" options for rRESPA integration via the
|
||||
"run_style respa"_run_style.html command.
|
||||
|
||||
:line
|
||||
|
||||
|
|
|
|||
|
|
@ -1497,8 +1497,9 @@ if desired.
|
|||
default Intel settings, as if the command "package intel * mixed
|
||||
balance -1" were used at the top of your input script. These settings
|
||||
can be changed by using the <A HREF = "package.html">package intel</A> command in
|
||||
your script if desired. The intel suffix will attempt to use styles
|
||||
from the OMP package if they are not present in the Intel package.
|
||||
your script if desired. If the USER-OMP package is installed, the
|
||||
intel suffix will make the omp suffix a second choice, if a requested
|
||||
style is not available in the USER-INTEL package.
|
||||
</P>
|
||||
<P>For the KOKKOS package, using this command-line switch also invokes
|
||||
the default KOKKOS settings, as if the command "package kokkos neigh
|
||||
|
|
@ -1511,9 +1512,9 @@ default OMP settings, as if the command "package omp *" were used at
|
|||
the top of your input script. These settings can be changed by using
|
||||
the <A HREF = "package.html">package omp</A> command in your script if desired.
|
||||
</P>
|
||||
<P>The <A HREF = "suffix.html">suffix</A> command can also be used set a suffix and it
|
||||
can also turn off or back on any suffix setting made via the command
|
||||
line.
|
||||
<P>The <A HREF = "suffix.html">suffix</A> command can also be used to set a suffix and
|
||||
it can also turn off or back on any suffix setting made via the
|
||||
command line.
|
||||
</P>
|
||||
<PRE>-var name value1 value2 ...
|
||||
</PRE>
|
||||
|
|
|
|||
|
|
@ -1491,8 +1491,9 @@ For the Intel package, using this command-line switch also invokes the
|
|||
default Intel settings, as if the command "package intel * mixed
|
||||
balance -1" were used at the top of your input script. These settings
|
||||
can be changed by using the "package intel"_package.html command in
|
||||
your script if desired. The intel suffix will attempt to use styles
|
||||
from the OMP package if they are not present in the Intel package.
|
||||
your script if desired. If the USER-OMP package is installed, the
|
||||
intel suffix will make the omp suffix a second choice, if a requested
|
||||
style is not available in the USER-INTEL package.
|
||||
|
||||
For the KOKKOS package, using this command-line switch also invokes
|
||||
the default KOKKOS settings, as if the command "package kokkos neigh
|
||||
|
|
@ -1505,9 +1506,9 @@ default OMP settings, as if the command "package omp *" were used at
|
|||
the top of your input script. These settings can be changed by using
|
||||
the "package omp"_package.html command in your script if desired.
|
||||
|
||||
The "suffix"_suffix.html command can also be used set a suffix and it
|
||||
can also turn off or back on any suffix setting made via the command
|
||||
line.
|
||||
The "suffix"_suffix.html command can also be used to set a suffix and
|
||||
it can also turn off or back on any suffix setting made via the
|
||||
command line.
|
||||
|
||||
-var name value1 value2 ... :pre
|
||||
|
||||
|
|
|
|||
|
|
@ -80,9 +80,9 @@ If the variant version does not exist, the standard version is
|
|||
created.
|
||||
</P>
|
||||
<P>When using the intel suffix, LAMMPS will first attempt to use a style
|
||||
with the intel suffix. If this does not exist, a style with the omp
|
||||
suffix is attempted. If this also does not exist, the style without
|
||||
any suffix is used.
|
||||
with the intel suffix. If the USER-OMP package is installed, the the
|
||||
omp suffix will be tried as a second choice, if a requested style is
|
||||
not available in the USER-INTEL package.
|
||||
</P>
|
||||
<P>If the specified style is <I>off</I>, then any previously specified suffix
|
||||
is temporarily disabled, whether it was specified by a command-line
|
||||
|
|
|
|||
|
|
@ -77,9 +77,9 @@ If the variant version does not exist, the standard version is
|
|||
created.
|
||||
|
||||
When using the intel suffix, LAMMPS will first attempt to use a style
|
||||
with the intel suffix. If this does not exist, a style with the omp
|
||||
suffix is attempted. If this also does not exist, the style without
|
||||
any suffix is used.
|
||||
with the intel suffix. If the USER-OMP package is installed, the the
|
||||
omp suffix will be tried as a second choice, if a requested style is
|
||||
not available in the USER-INTEL package.
|
||||
|
||||
If the specified style is {off}, then any previously specified suffix
|
||||
is temporarily disabled, whether it was specified by a command-line
|
||||
|
|
|
|||
Loading…
Reference in New Issue