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doc/package.html
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doc/package.html
|
|
@ -68,11 +68,21 @@
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<I>tptask</I> value = Ntptask
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Ntptask = max number of threads to use on coprocessor for each MPI task
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<I>kokkos</I> args = keyword value ...
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one or more keyword/value pairs may be appended
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keywords = <I>neigh</I> or <I>comm/exchange</I> or <I>comm/forward</I>
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zero or more keyword/value pairs may be appended
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keywords = <I>neigh</I> or <I>comm</I> or <I>comm/exchange</I> or <I>comm/forward</I>
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<I>neigh</I> value = <I>full</I> or <I>half/thread</I> or <I>half</I> or <I>n2</I> or <I>full/cluster</I>
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full = full neighbor list
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half/thread = half neighbor list built in thread-safe manner
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half = half neighbor list, not thread-safe, only use when 1 thread/MPI task
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n2 = non-binning neighbor list build, O(N^2) algorithm
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full/cluster = full neighbor list with clustered groups of atoms
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<I>comm</I> value = <I>no</I> or <I>host</I> or <I>device</I>
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use value for both comm/exchange and comm/forward
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<I>comm/exchange</I> value = <I>no</I> or <I>host</I> or <I>device</I>
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<I>comm/forward</I> value = <I>no</I> or <I>host</I> or <I>device</I>
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no = perform communication pack/unpack in non-KOKKOS mode
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host = perform pack/unpack on host (e.g. with OpenMP threading)
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device = perform pack/unpack on device (e.g. on GPU)
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<I>omp</I> args = Nthreads keyword value ...
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Nthread = # of OpenMP threads to associate with each MPI process
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zero or more keyword/value pairs may be appended
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@ -88,47 +98,59 @@
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<PRE>package gpu 1
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package gpu 1 split 0.75
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package gpu 2 split -1.0
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package cuda gpu/node/special 2 0 2
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package cuda test 3948
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package kokkos neigh half/thread comm/forward device
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package omp 0 neigh yes
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package cuda 2 gpuID 0 2
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package cuda 1 test 3948
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package kokkos neigh half/thread comm device
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package omp 0 neigh no
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package omp 4
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package intel * mixed balance -1
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</PRE>
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<P><B>Description:</B>
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</P>
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<P>This command invokes package-specific settings. Currently the
|
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following packages use it: USER-CUDA, GPU, USER-INTEL, KOKKOS, and
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USER-OMP.
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<P>This command invokes package-specific settings for the various
|
||||
accelerator packages available in LAMMPS. Currently the following
|
||||
packages use settings from this command: USER-CUDA, GPU, USER-INTEL,
|
||||
KOKKOS, and USER-OMP.
|
||||
</P>
|
||||
<P>If allows calling multiple times, all options set to their
|
||||
defaults, whether specified or not.
|
||||
<P>If this command is specified in an input script, it must be near the
|
||||
top of the script, before the simulation box has been defined. This
|
||||
is because it specifies settings that the accelerator packages use in
|
||||
their intialization, before a simultion is defined.
|
||||
</P>
|
||||
<P>Talk about command line switch -pk as alternate option.
|
||||
<P>This command can also be specified from the command-line when
|
||||
launching LAMMPS, using the "-pk" <A HREF = "Section_start.html#start_7">command-line
|
||||
switch</A>. The syntax is exactly the same as
|
||||
when used in an input script.
|
||||
</P>
|
||||
<P>Which packages require it to be invoked, only CUDA
|
||||
this is b/c can only be invoked once
|
||||
vs optional: all others? and allow multiple invokes
|
||||
<P>Note that all of the accelerator packages require the package command
|
||||
to be specified (except the OPT package), if the package is to be used
|
||||
in a simulation (LAMMPS can be built with an accelerator package
|
||||
without using it in a particular simulation). However, in all cases,
|
||||
a default version of the command is typically invoked by other
|
||||
accelerator settings.
|
||||
</P>
|
||||
<P>Must be invoked early in script, before simulation box is defined.
|
||||
<P>The USER-CUDA and KOKKOS packages require a "-c on" or "-k on"
|
||||
<A HREF = "Section_start.html#start_7">command-line switch</A> respectively, which
|
||||
invokes a "package cuda" or "package kokkos" command with default
|
||||
settings.
|
||||
</P>
|
||||
<P>To use the accelerated GPU and USER-OMP styles, the use of the package
|
||||
command is required. However, as described in the "Defaults" section
|
||||
below, if you use the "-sf gpu" or "-sf omp" <A HREF = "Section_start.html#start_7">command-line
|
||||
options</A> to enable use of these styles,
|
||||
then default package settings are enabled. In that case you only need
|
||||
to use the package command if you want to change the defaults.
|
||||
<P>For the GPU, USER-INTEL, and USER-OMP packages, if a "-sf gpu" or "-sf
|
||||
intel" or "-sf omp" <A HREF = "Section_start.html#start_7">command-line switch</A>
|
||||
is used to auto-append accelerator suffixes to various styles in the
|
||||
input script, then those switches also invoke a "package gpu",
|
||||
"package intel", or "package omp" command with default settings.
|
||||
</P>
|
||||
<P>To use the accelerated USER-CUDA and KOKKOS styles, the package
|
||||
command is not required as defaults are assigned internally. You only
|
||||
need to use the package command if you want to change the defaults.
|
||||
<P>IMPORTANT NOTE: A package command for a particular style can be
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||||
invoked multiple times when a simulation is setup, e.g. by the "-c
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||||
on", "-k on", "-sf", and "-pk" <A HREF = "Section_start.html#start_7">command-line
|
||||
switches</A>, and by using this command in an
|
||||
input script. Each time it is used all of the style options are set,
|
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either to default values or to specified settings. I.e. settings from
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||||
previous invocations do not persist across multiple invocations.
|
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</P>
|
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<P>See <A HREF = "Section_accelerate.html">Section_accelerate</A> of the manual for
|
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more details about using these various packages for accelerating
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LAMMPS calculations.
|
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</P>
|
||||
<P>Package GPU always sets newton pair off. Not so for USER-CUDA
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add newton options to GPU, CUDA, KOKKOS.
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<P>See the <A HREF = "Section_accelerate.html">Section Accelerate</A> section of the
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manual for more details about using the various accelerator packages
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for speeding up LAMMPS simulations.
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</P>
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<HR>
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@ -335,32 +357,44 @@ generation Xeon Phi chip.
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<P>The <I>kokkos</I> style invokes settings associated with the use of the
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KOKKOS package.
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</P>
|
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<P>The <I>neigh</I> keyword determines what kinds of neighbor lists are built.
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A value of <I>half</I> uses half-neighbor lists, the same as used by most
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pair styles in LAMMPS. A value of <I>half/thread</I> uses a threadsafe
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||||
variant of the half-neighbor list. It should be used instead of
|
||||
<I>half</I> when running with threads on a CPU. A value of <I>full</I> uses a
|
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full-neighborlist, i.e. f_ij and f_ji are both calculated. This
|
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performs twice as much computation as the <I>half</I> option, however that
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can be a win because it is threadsafe and doesn't require atomic
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operations. A value of <I>full/cluster</I> is an experimental neighbor
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||||
style, where particles interact with all particles within a small
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||||
cluster, if at least one of the clusters particles is within the
|
||||
neighbor cutoff range. This potentially allows for better
|
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vectorization on architectures such as the Intel Phi. If also reduces
|
||||
the size of the neighbor list by roughly a factor of the cluster size,
|
||||
thus reducing the total memory footprint considerably.
|
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<P>All of the settings are optional keyword/value pairs. Each has a
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default value as listed below.
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</P>
|
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<P>The <I>comm/exchange</I> and <I>comm/forward</I> keywords determine whether the
|
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host or device performs the packing and unpacking of data when
|
||||
communicating information between processors. "Exchange"
|
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<P>The <I>neigh</I> keyword determines how neighbor lists are built. A value
|
||||
of <I>half</I> uses half-neighbor lists, the same as used by most pair
|
||||
styles in LAMMPS. A value of <I>half/thread</I> uses a thread-safe variant
|
||||
of the half-neighbor list. It should be used instead of <I>half</I> when
|
||||
running with more than 1 threads per MPI task on a CPU. A value of
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<I>n2</I> uses an O(N^2) algorithm to build the neighbor list without
|
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binning, where N = # of atoms on a processor. It is typically slower
|
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than the other methods, which use binning.
|
||||
</P>
|
||||
<P>A value of <I>full</I> uses a full neighbor lists and is the default. This
|
||||
performs twice as much computation as the <I>half</I> option, however that
|
||||
is often a win because it is thread-safe and doesn't require atomic
|
||||
operations in the calculation of pair forces.
|
||||
</P>
|
||||
<P>A value of <I>full/cluster</I> is an experimental neighbor style, where
|
||||
particles interact with all particles within a small cluster, if at
|
||||
least one of the clusters particles is within the neighbor cutoff
|
||||
range. This potentially allows for better vectorization on
|
||||
architectures such as the Intel Phi. If also reduces the size of the
|
||||
neighbor list by roughly a factor of the cluster size, thus reducing
|
||||
the total memory footprint considerably.
|
||||
</P>
|
||||
<P>The <I>comm</I> and <I>comm/exchange</I> and <I>comm/forward</I> keywords determine
|
||||
whether the host or device performs the packing and unpacking of data
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||||
when communicating per-atom data between processors. "Exchange"
|
||||
communication happens only on timesteps that neighbor lists are
|
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rebuilt. The data is only for atoms that migrate to new processors.
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"Forward" communication happens every timestep. The data is for atom
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coordinates and any other atom properties that needs to be updated for
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||||
ghost atoms owned by each processor.
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||||
</P>
|
||||
<P>The value options for these keywords are <I>no</I> or <I>host</I> or <I>device</I>.
|
||||
<P>The <I>comm</I> keyword is simply a short-cut to set the same value
|
||||
for both the <I>comm/exchange</I> and <I>comm/forward</I> keywords.
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||||
</P>
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||||
<P>The value options for all 3 keywords are <I>no</I> or <I>host</I> or <I>device</I>.
|
||||
A value of <I>no</I> means to use the standard non-KOKKOS method of
|
||||
packing/unpacking data for the communication. A value of <I>host</I> means
|
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to use the host, typically a multi-core CPU, and perform the
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|
|
@ -369,10 +403,12 @@ to use the device, typically a GPU, to perform the packing/unpacking
|
|||
operation.
|
||||
</P>
|
||||
<P>The optimal choice for these keywords depends on the input script and
|
||||
the hardware used. The <I>no</I> value is useful for verifying that Kokkos
|
||||
code is working correctly. It may also be the fastest choice when
|
||||
using Kokkos styles in MPI-only mode (i.e. with a thread count of 1).
|
||||
When running on CPUs or Xeon Phi, the <I>host</I> and <I>device</I> values work
|
||||
the hardware used. The <I>no</I> value is useful for verifying that the
|
||||
Kokkos-based <I>host</I> and <I>device</I> values are working correctly. It may
|
||||
also be the fastest choice when using Kokkos styles in MPI-only mode
|
||||
(i.e. with a thread count of 1).
|
||||
</P>
|
||||
<P>When running on CPUs or Xeon Phi, the <I>host</I> and <I>device</I> values work
|
||||
identically. When using GPUs, the <I>device</I> value will typically be
|
||||
optimal if all of your styles used in your input script are supported
|
||||
by the KOKKOS package. In this case data can stay on the GPU for many
|
||||
|
|
@ -476,11 +512,13 @@ setting</A>
|
|||
</P>
|
||||
<P><B>Default:</B>
|
||||
</P>
|
||||
<P>To use the USER-CUDA package, the package cuda command must be invoked
|
||||
explicitly in your input script or via the "-pk cuda" <A HREF = "Section_start.html#start_7">command-line
|
||||
switch</A>. This will set the # of GPUs/node.
|
||||
The options defaults are gpuID = 0 to Ngpu-1, timing = not enabled,
|
||||
test = not enabled, and thread = auto.
|
||||
<P>For the USER-CUDA package, the default is Ngpu = 1 and the option
|
||||
defaults are gpuID = 0 to Ngpu-1, timing = not enabled, test = not
|
||||
enabled, and thread = auto. These settings are made automatically by
|
||||
the required "-c on" <A HREF = "Section_start.html#start_7">command-line switch</A>.
|
||||
You can change them bu using the package cuda command in your input
|
||||
script or via the "-pk cuda" <A HREF = "Section_start.html#start_7">command-line
|
||||
switch</A>.
|
||||
</P>
|
||||
<P>For the GPU package, the default is Ngpu = 1 and the option defaults
|
||||
are neigh = yes, split = 1.0, gpuID = 0 to Ngpu-1, tpa = 1, binsize =
|
||||
|
|
@ -491,24 +529,21 @@ must invoke the package gpu command in your input script or via the
|
|||
"-pk gpu" <A HREF = "Section_start.html#start_7">command-line switch</A>.
|
||||
</P>
|
||||
<P>For the USER-INTEL package, the default is Nphi = 1 and the option
|
||||
defaults are prec = mixed, balance = -1, tpc = 4, tptask = 240. The
|
||||
default ghost option is determined by the pair style being used. This
|
||||
value used is output to the screen in the offload report at the end of
|
||||
each run. These settings are made automatically if the "-sf intel"
|
||||
<A HREF = "Section_start.html#start_7">command-line switch</A> is used. If it is
|
||||
not used, you must invoke the package intel command in your input
|
||||
script or or via the "-pk intel" <A HREF = "Section_start.html#start_7">command-line
|
||||
switch</A>.
|
||||
defaults are prec = mixed, balance = -1, tpc = 4, tptask = 240. Note
|
||||
that all of these settings, except "prec", are ignored if LAMMPS was
|
||||
not built with Xeon Phi coprocessor support. The default ghost option
|
||||
is determined by the pair style being used. This value is output to
|
||||
the screen in the offload report at the end of each run. These
|
||||
settings are made automatically if the "-sf intel" <A HREF = "Section_start.html#start_7">command-line
|
||||
switch</A> is used. If it is not used, you
|
||||
must invoke the package intel command in your input script or or via
|
||||
the "-pk intel" <A HREF = "Section_start.html#start_7">command-line switch</A>.
|
||||
</P>
|
||||
<P>The default settings for the KOKKOS package are "package kokkos neigh
|
||||
full comm/exchange host comm/forward host". This is the case whether
|
||||
the "-sf kk" <A HREF = "Section_start.html#start_7">command-line switch</A> is used
|
||||
or not.
|
||||
To use the KOKKOS package, the package kokkos command must be invoked
|
||||
explicitly in your input script or via the "-pk kokkos" <A HREF = "Section_start.html#start_7">command-line
|
||||
switch</A>. This will set the # of GPUs/node.
|
||||
The options defaults are gpuID = 0 to Ngpu-1, timing = not enabled,
|
||||
test = not enabled, and thread = auto.
|
||||
<P>For the KOKKOS package, the option defaults neigh = full and comm =
|
||||
host. These settings are made automatically by the required "-k on"
|
||||
<A HREF = "Section_start.html#start_7">command-line switch</A>. You can change them
|
||||
bu using the package kokkos command in your input script or via the
|
||||
"-pk kokkos" <A HREF = "Section_start.html#start_7">command-line switch</A>.
|
||||
</P>
|
||||
<P>For the OMP package, the default is Nthreads = 0 and the option
|
||||
defaults are neigh = yes. These settings are made automatically if
|
||||
|
|
|
|||
186
doc/package.txt
186
doc/package.txt
|
|
@ -63,11 +63,21 @@ args = arguments specific to the style :l
|
|||
{tptask} value = Ntptask
|
||||
Ntptask = max number of threads to use on coprocessor for each MPI task
|
||||
{kokkos} args = keyword value ...
|
||||
one or more keyword/value pairs may be appended
|
||||
keywords = {neigh} or {comm/exchange} or {comm/forward}
|
||||
zero or more keyword/value pairs may be appended
|
||||
keywords = {neigh} or {comm} or {comm/exchange} or {comm/forward}
|
||||
{neigh} value = {full} or {half/thread} or {half} or {n2} or {full/cluster}
|
||||
full = full neighbor list
|
||||
half/thread = half neighbor list built in thread-safe manner
|
||||
half = half neighbor list, not thread-safe, only use when 1 thread/MPI task
|
||||
n2 = non-binning neighbor list build, O(N^2) algorithm
|
||||
full/cluster = full neighbor list with clustered groups of atoms
|
||||
{comm} value = {no} or {host} or {device}
|
||||
use value for both comm/exchange and comm/forward
|
||||
{comm/exchange} value = {no} or {host} or {device}
|
||||
{comm/forward} value = {no} or {host} or {device}
|
||||
no = perform communication pack/unpack in non-KOKKOS mode
|
||||
host = perform pack/unpack on host (e.g. with OpenMP threading)
|
||||
device = perform pack/unpack on device (e.g. on GPU)
|
||||
{omp} args = Nthreads keyword value ...
|
||||
Nthread = # of OpenMP threads to associate with each MPI process
|
||||
zero or more keyword/value pairs may be appended
|
||||
|
|
@ -82,47 +92,59 @@ args = arguments specific to the style :l
|
|||
package gpu 1
|
||||
package gpu 1 split 0.75
|
||||
package gpu 2 split -1.0
|
||||
package cuda gpu/node/special 2 0 2
|
||||
package cuda test 3948
|
||||
package kokkos neigh half/thread comm/forward device
|
||||
package omp 0 neigh yes
|
||||
package cuda 2 gpuID 0 2
|
||||
package cuda 1 test 3948
|
||||
package kokkos neigh half/thread comm device
|
||||
package omp 0 neigh no
|
||||
package omp 4
|
||||
package intel * mixed balance -1 :pre
|
||||
|
||||
[Description:]
|
||||
|
||||
This command invokes package-specific settings. Currently the
|
||||
following packages use it: USER-CUDA, GPU, USER-INTEL, KOKKOS, and
|
||||
USER-OMP.
|
||||
This command invokes package-specific settings for the various
|
||||
accelerator packages available in LAMMPS. Currently the following
|
||||
packages use settings from this command: USER-CUDA, GPU, USER-INTEL,
|
||||
KOKKOS, and USER-OMP.
|
||||
|
||||
If allows calling multiple times, all options set to their
|
||||
defaults, whether specified or not.
|
||||
If this command is specified in an input script, it must be near the
|
||||
top of the script, before the simulation box has been defined. This
|
||||
is because it specifies settings that the accelerator packages use in
|
||||
their intialization, before a simultion is defined.
|
||||
|
||||
Talk about command line switch -pk as alternate option.
|
||||
This command can also be specified from the command-line when
|
||||
launching LAMMPS, using the "-pk" "command-line
|
||||
switch"_Section_start.html#start_7. The syntax is exactly the same as
|
||||
when used in an input script.
|
||||
|
||||
Which packages require it to be invoked, only CUDA
|
||||
this is b/c can only be invoked once
|
||||
vs optional: all others? and allow multiple invokes
|
||||
Note that all of the accelerator packages require the package command
|
||||
to be specified (except the OPT package), if the package is to be used
|
||||
in a simulation (LAMMPS can be built with an accelerator package
|
||||
without using it in a particular simulation). However, in all cases,
|
||||
a default version of the command is typically invoked by other
|
||||
accelerator settings.
|
||||
|
||||
Must be invoked early in script, before simulation box is defined.
|
||||
The USER-CUDA and KOKKOS packages require a "-c on" or "-k on"
|
||||
"command-line switch"_Section_start.html#start_7 respectively, which
|
||||
invokes a "package cuda" or "package kokkos" command with default
|
||||
settings.
|
||||
|
||||
To use the accelerated GPU and USER-OMP styles, the use of the package
|
||||
command is required. However, as described in the "Defaults" section
|
||||
below, if you use the "-sf gpu" or "-sf omp" "command-line
|
||||
options"_Section_start.html#start_7 to enable use of these styles,
|
||||
then default package settings are enabled. In that case you only need
|
||||
to use the package command if you want to change the defaults.
|
||||
For the GPU, USER-INTEL, and USER-OMP packages, if a "-sf gpu" or "-sf
|
||||
intel" or "-sf omp" "command-line switch"_Section_start.html#start_7
|
||||
is used to auto-append accelerator suffixes to various styles in the
|
||||
input script, then those switches also invoke a "package gpu",
|
||||
"package intel", or "package omp" command with default settings.
|
||||
|
||||
To use the accelerated USER-CUDA and KOKKOS styles, the package
|
||||
command is not required as defaults are assigned internally. You only
|
||||
need to use the package command if you want to change the defaults.
|
||||
IMPORTANT NOTE: A package command for a particular style can be
|
||||
invoked multiple times when a simulation is setup, e.g. by the "-c
|
||||
on", "-k on", "-sf", and "-pk" "command-line
|
||||
switches"_Section_start.html#start_7, and by using this command in an
|
||||
input script. Each time it is used all of the style options are set,
|
||||
either to default values or to specified settings. I.e. settings from
|
||||
previous invocations do not persist across multiple invocations.
|
||||
|
||||
See "Section_accelerate"_Section_accelerate.html of the manual for
|
||||
more details about using these various packages for accelerating
|
||||
LAMMPS calculations.
|
||||
|
||||
Package GPU always sets newton pair off. Not so for USER-CUDA
|
||||
add newton options to GPU, CUDA, KOKKOS.
|
||||
See the "Section Accelerate"_Section_accelerate.html section of the
|
||||
manual for more details about using the various accelerator packages
|
||||
for speeding up LAMMPS simulations.
|
||||
|
||||
:line
|
||||
|
||||
|
|
@ -329,32 +351,44 @@ generation Xeon Phi chip.
|
|||
The {kokkos} style invokes settings associated with the use of the
|
||||
KOKKOS package.
|
||||
|
||||
The {neigh} keyword determines what kinds of neighbor lists are built.
|
||||
A value of {half} uses half-neighbor lists, the same as used by most
|
||||
pair styles in LAMMPS. A value of {half/thread} uses a threadsafe
|
||||
variant of the half-neighbor list. It should be used instead of
|
||||
{half} when running with threads on a CPU. A value of {full} uses a
|
||||
full-neighborlist, i.e. f_ij and f_ji are both calculated. This
|
||||
performs twice as much computation as the {half} option, however that
|
||||
can be a win because it is threadsafe and doesn't require atomic
|
||||
operations. A value of {full/cluster} is an experimental neighbor
|
||||
style, where particles interact with all particles within a small
|
||||
cluster, if at least one of the clusters particles is within the
|
||||
neighbor cutoff range. This potentially allows for better
|
||||
vectorization on architectures such as the Intel Phi. If also reduces
|
||||
the size of the neighbor list by roughly a factor of the cluster size,
|
||||
thus reducing the total memory footprint considerably.
|
||||
All of the settings are optional keyword/value pairs. Each has a
|
||||
default value as listed below.
|
||||
|
||||
The {comm/exchange} and {comm/forward} keywords determine whether the
|
||||
host or device performs the packing and unpacking of data when
|
||||
communicating information between processors. "Exchange"
|
||||
The {neigh} keyword determines how neighbor lists are built. A value
|
||||
of {half} uses half-neighbor lists, the same as used by most pair
|
||||
styles in LAMMPS. A value of {half/thread} uses a thread-safe variant
|
||||
of the half-neighbor list. It should be used instead of {half} when
|
||||
running with more than 1 threads per MPI task on a CPU. A value of
|
||||
{n2} uses an O(N^2) algorithm to build the neighbor list without
|
||||
binning, where N = # of atoms on a processor. It is typically slower
|
||||
than the other methods, which use binning.
|
||||
|
||||
A value of {full} uses a full neighbor lists and is the default. This
|
||||
performs twice as much computation as the {half} option, however that
|
||||
is often a win because it is thread-safe and doesn't require atomic
|
||||
operations in the calculation of pair forces.
|
||||
|
||||
A value of {full/cluster} is an experimental neighbor style, where
|
||||
particles interact with all particles within a small cluster, if at
|
||||
least one of the clusters particles is within the neighbor cutoff
|
||||
range. This potentially allows for better vectorization on
|
||||
architectures such as the Intel Phi. If also reduces the size of the
|
||||
neighbor list by roughly a factor of the cluster size, thus reducing
|
||||
the total memory footprint considerably.
|
||||
|
||||
The {comm} and {comm/exchange} and {comm/forward} keywords determine
|
||||
whether the host or device performs the packing and unpacking of data
|
||||
when communicating per-atom data between processors. "Exchange"
|
||||
communication happens only on timesteps that neighbor lists are
|
||||
rebuilt. The data is only for atoms that migrate to new processors.
|
||||
"Forward" communication happens every timestep. The data is for atom
|
||||
coordinates and any other atom properties that needs to be updated for
|
||||
ghost atoms owned by each processor.
|
||||
|
||||
The value options for these keywords are {no} or {host} or {device}.
|
||||
The {comm} keyword is simply a short-cut to set the same value
|
||||
for both the {comm/exchange} and {comm/forward} keywords.
|
||||
|
||||
The value options for all 3 keywords are {no} or {host} or {device}.
|
||||
A value of {no} means to use the standard non-KOKKOS method of
|
||||
packing/unpacking data for the communication. A value of {host} means
|
||||
to use the host, typically a multi-core CPU, and perform the
|
||||
|
|
@ -363,9 +397,11 @@ to use the device, typically a GPU, to perform the packing/unpacking
|
|||
operation.
|
||||
|
||||
The optimal choice for these keywords depends on the input script and
|
||||
the hardware used. The {no} value is useful for verifying that Kokkos
|
||||
code is working correctly. It may also be the fastest choice when
|
||||
using Kokkos styles in MPI-only mode (i.e. with a thread count of 1).
|
||||
the hardware used. The {no} value is useful for verifying that the
|
||||
Kokkos-based {host} and {device} values are working correctly. It may
|
||||
also be the fastest choice when using Kokkos styles in MPI-only mode
|
||||
(i.e. with a thread count of 1).
|
||||
|
||||
When running on CPUs or Xeon Phi, the {host} and {device} values work
|
||||
identically. When using GPUs, the {device} value will typically be
|
||||
optimal if all of your styles used in your input script are supported
|
||||
|
|
@ -470,11 +506,13 @@ setting"_Section_start.html#start_7
|
|||
|
||||
[Default:]
|
||||
|
||||
To use the USER-CUDA package, the package cuda command must be invoked
|
||||
explicitly in your input script or via the "-pk cuda" "command-line
|
||||
switch"_Section_start.html#start_7. This will set the # of GPUs/node.
|
||||
The options defaults are gpuID = 0 to Ngpu-1, timing = not enabled,
|
||||
test = not enabled, and thread = auto.
|
||||
For the USER-CUDA package, the default is Ngpu = 1 and the option
|
||||
defaults are gpuID = 0 to Ngpu-1, timing = not enabled, test = not
|
||||
enabled, and thread = auto. These settings are made automatically by
|
||||
the required "-c on" "command-line switch"_Section_start.html#start_7.
|
||||
You can change them bu using the package cuda command in your input
|
||||
script or via the "-pk cuda" "command-line
|
||||
switch"_Section_start.html#start_7.
|
||||
|
||||
For the GPU package, the default is Ngpu = 1 and the option defaults
|
||||
are neigh = yes, split = 1.0, gpuID = 0 to Ngpu-1, tpa = 1, binsize =
|
||||
|
|
@ -485,24 +523,21 @@ must invoke the package gpu command in your input script or via the
|
|||
"-pk gpu" "command-line switch"_Section_start.html#start_7.
|
||||
|
||||
For the USER-INTEL package, the default is Nphi = 1 and the option
|
||||
defaults are prec = mixed, balance = -1, tpc = 4, tptask = 240. The
|
||||
default ghost option is determined by the pair style being used. This
|
||||
value used is output to the screen in the offload report at the end of
|
||||
each run. These settings are made automatically if the "-sf intel"
|
||||
"command-line switch"_Section_start.html#start_7 is used. If it is
|
||||
not used, you must invoke the package intel command in your input
|
||||
script or or via the "-pk intel" "command-line
|
||||
switch"_Section_start.html#start_7.
|
||||
defaults are prec = mixed, balance = -1, tpc = 4, tptask = 240. Note
|
||||
that all of these settings, except "prec", are ignored if LAMMPS was
|
||||
not built with Xeon Phi coprocessor support. The default ghost option
|
||||
is determined by the pair style being used. This value is output to
|
||||
the screen in the offload report at the end of each run. These
|
||||
settings are made automatically if the "-sf intel" "command-line
|
||||
switch"_Section_start.html#start_7 is used. If it is not used, you
|
||||
must invoke the package intel command in your input script or or via
|
||||
the "-pk intel" "command-line switch"_Section_start.html#start_7.
|
||||
|
||||
The default settings for the KOKKOS package are "package kokkos neigh
|
||||
full comm/exchange host comm/forward host". This is the case whether
|
||||
the "-sf kk" "command-line switch"_Section_start.html#start_7 is used
|
||||
or not.
|
||||
To use the KOKKOS package, the package kokkos command must be invoked
|
||||
explicitly in your input script or via the "-pk kokkos" "command-line
|
||||
switch"_Section_start.html#start_7. This will set the # of GPUs/node.
|
||||
The options defaults are gpuID = 0 to Ngpu-1, timing = not enabled,
|
||||
test = not enabled, and thread = auto.
|
||||
For the KOKKOS package, the option defaults neigh = full and comm =
|
||||
host. These settings are made automatically by the required "-k on"
|
||||
"command-line switch"_Section_start.html#start_7. You can change them
|
||||
bu using the package kokkos command in your input script or via the
|
||||
"-pk kokkos" "command-line switch"_Section_start.html#start_7.
|
||||
|
||||
For the OMP package, the default is Nthreads = 0 and the option
|
||||
defaults are neigh = yes. These settings are made automatically if
|
||||
|
|
@ -510,4 +545,3 @@ the "-sf omp" "command-line switch"_Section_start.html#start_7 is
|
|||
used. If it is not used, you must invoke the package omp command in
|
||||
your input script or via the "-pk omp" "command-line
|
||||
switch"_Section_start.html#start_7.
|
||||
|
||||
|
|
|
|||
Loading…
Reference in New Issue