Developer Reference

Local Hydra Options

This section describes the local options of the Intel® MPI Library's Hydra process manager. Local options are applied only to the argument set they are specified in. Argument sets are separated by a colon '
:
'.

-n
<number-of-processes>
or
-np
<number-of-processes>

Use this option to set the number of MPI processes to run with the current argument set.

-env
<envar> <value>

Use this option to set the
<envar>
environment variable to the specified
<value>
for all MPI processes in the current argument set.

-envall

Use this option to propagate all environment variables in the current argument set. See the
I_MPI_HYDRA_ENV
environment variable for more details.

-envnone

Use this option to suppress propagation of any environment variables to the MPI processes in the current argument set.
The option does not work for localhost.

-envexcl
<list-of-envvar-names>

Use this option to suppress propagation of the listed environment variables to the MPI processes in the current argument set.

-envlist
<list>

Use this option to pass a list of environment variables with their current values.
<list>
is a comma separated list of environment variables to be sent to the MPI processes.

-host
<nodename>

Use this option to specify a particular
<nodename>
on which the MPI processes are to be run. For example, the following command executes
a.out
on hosts
host1
and
host2
:
$ mpiexec.hydra -n 2 -host host1 ./a.out : -n 2 -host host2 ./a.out

-path
<directory>

Use this option to specify the path to the
<executable>
file to be run in the current argument set.

-wdir
<directory>

Use this option to specify the working directory in which the
<executable>
file runs in the current argument set.

Product and Performance Information

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Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex.