Developer Reference

mpiexec.hydra

Launches an MPI job using the Hydra process manager.
Syntax
mpiexec
.hydra
<g-options> <l-options> <executable>
or
mpiexec
.hydra
<g-options> <l-options> <executable1>
:
<l-options> <executable2>
Arguments
<g-options>
Global options that apply to all MPI processes
<l-options>
Local options that apply to a single argument set
<executable>
./a.out
or
path
/
name
of the executable file
Description
Use the
mpiexec
.hydra
utility to run MPI applications using the Hydra process manager.
Use the first short command-line syntax to start all MPI processes of the
<executable>
with the single set of arguments. For example, the following command executes
a.out
over the specified processes and hosts:
$ mpiexec.hydra -f <hostfile> -n <# of processes> ./a.out
where:
  • <# of processes>
    specifies the number of processes on which to run the
    a.out
    executable
  • <hostfile>
    specifies a list of hosts on which to run the
    a.out
    executable
Use the second long command-line syntax to set different argument sets for different MPI program runs. For example, the following command executes two different binaries with different argument sets:
$ mpiexec.hydra -f <hostfile> -env <VAR1> <VAL1> -n 2 ./a.out : \ -env <VAR2> <VAL2> -n 2 ./b.out
You need to distinguish global options from local options. In a command-line syntax, place the local options after the global options.

Product and Performance Information

1

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