Environment Variables

Set the host file to run the application.

Syntax

I_MPI_HYDRA_HOST_FILE=<arg>

Deprecated Syntax

HYDRA_HOST_FILE=<arg>

Arguments

`<arg>`	String parameter
`<hostsfile>`	Full or relative path to the host file

Description

Set this environment variable to specify the hosts file.

I_MPI_HYDRA_DEBUG

Print out the debug information.

Syntax

I_MPI_HYDRA_DEBUG=<arg>

Arguments

`<arg>`	Binary indicator
`enable \| yes \| on \| 1`	Turn on the debug output
`disable \| no \| off \| 0`	Turn off the debug output. This is the default value

Description

Set this environment variable to enable the debug mode.

I_MPI_HYDRA_ENV

Control the environment propagation.

Syntax

I_MPI_HYDRA_ENV=<arg>

Arguments

`<arg>`	String parameter
`all`	Pass all environment to all MPI processes

Description

Set this environment variable to control the environment propagation to the MPI processes. By default, the entire launching node environment is passed to the MPI processes. Setting this variable also overwrites environment variables set by the remote shell.

I_MPI_JOB_TIMEOUT, I_MPI_MPIEXEC_TIMEOUT

(MPIEXEC_TIMEOUT)

Set the timeout period for mpiexec.hydra.

Syntax

I_MPI_JOB_TIMEOUT=<timeout>

I_MPI_MPIEXEC_TIMEOUT=<timeout>

Deprecated Syntax

MPIEXEC_TIMEOUT=<timeout>

Arguments

`<timeout>`	Define `mpiexec.hydra` timeout period in seconds
`<n>` `>= 0`	The default timeout value is zero, which means no timeout.

Description

Set this environment variable to make mpiexec.hydra terminate the job in <timeout> seconds after its launch. The <timeout> value should be greater than zero. Otherwise the environment variable setting is ignored.

Note:

Set the I_MPI_JOB_TIMEOUT environment variable in the shell environment before executing the mpiexec.hydra command. Do not use the -genv or -env options to set the <timeout> value. Those options are used for passing environment variables to the MPI process environment.

I_MPI_JOB_TIMEOUT_SIGNAL

(MPIEXEC_TIMEOUT_SIGNAL)

Define the signal to be sent when a job is terminated because of a timeout.

Syntax

I_MPI_JOB_TIMEOUT_SIGNAL=<number>

Deprecated Syntax

MPIEXEC_TIMEOUT_SIGNAL=<number>

Arguments

`<number>`	Define signal number
`<n>` `> 0`	The default value is `9` `(SIGKILL)`

Description

Define a signal number sent to stop the MPI job if the timeout period specified by the I_MPI_JOB_TIMEOUT environment variable expires. If you set a signal number unsupported by the system, the mpiexec.hydra operation prints a warning message and continues the task termination using the default signal number 9 (SIGKILL).

I_MPI_JOB_ABORT_SIGNAL

Define a signal to be sent to all processes when a job is terminated unexpectedly.

Syntax

I_MPI_JOB_ABORT_SIGNAL=<number>

Arguments

`<number>`	Define signal number
`<n>` `> 0`	The default value is `9` `(SIGKILL)`

Description

Set this environment variable to define a signal for task termination. If you set an unsupported signal number, mpiexec.hydra prints a warning message and uses the default signal 9 (SIGKILL).

I_MPI_JOB_SIGNAL_PROPAGATION

(MPIEXEC_SIGNAL_PROPAGATION)

Control signal propagation.

Syntax

I_MPI_JOB_SIGNAL_PROPAGATION=<arg>

Deprecated Syntax

MPIEXEC_SIGNAL_PROPAGATION=<arg>

Arguments

`<arg>`	Binary indicator
`enable \| yes \| on \| 1`	Turn on propagation
`disable \| no \| off \| 0`	Turn off propagation. This is the default value

Description

Set this environment variable to control propagation of the signals (SIGINT, SIGALRM, and SIGTERM). If you enable signal propagation, the received signal is sent to all processes of the MPI job. If you disable signal propagation, all processes of the MPI job are stopped with the default signal 9 (SIGKILL).

I_MPI_HYDRA_BOOTSTRAP

Set the bootstrap server.

Syntax

I_MPI_HYDRA_BOOTSTRAP=<arg>

Arguments

`<arg>`	String parameter
`ssh`	Use secure shell. This is the default value
`rsh`	Use remote shell
`pdsh`	Use parallel distributed shell
`fork`	Use fork call
`slurm`	Use SLURM* `srun` command
`ll`	Use LoadLeveler* `llspawn.stdio` command
`lsf`	Use LSF `blaunch` command
`sge`	Use Oracle Grid Engine* `qrsh` command
`jmi`	Use Job Manager Interface (tighter integration)

Description

Set this environment variable to specify the bootstrap server.

Note:

Set the I_MPI_HYDRA_BOOTSTRAP environment variable in the shell environment before executing the mpiexec.hydra command. Do not use the -env option to set the <arg> value. This option is used for passing environment variables to the MPI process environment.

I_MPI_HYDRA_BOOTSTRAP_EXEC

Set the executable to be used as a bootstrap server.

Syntax

I_MPI_HYDRA_BOOTSTRAP_EXEC=<arg>

Arguments

`<arg>`	String parameter
`<``executable``>`	The name of the executable

Description

Set this environment variable to specify the executable to be used as a bootstrap server.

I_MPI_HYDRA_RMK

Use the resource management kernel.

Syntax

I_MPI_HYDRA_RMK=<arg>

Arguments

`<arg>`	String parameter
`<rmk>`	Resource management kernel. The only supported value is `pbs`

Description

Set this environment variable to use the pbs resource management kernel. Intel® MPI Library only supports pbs.

I_MPI_HYDRA_PMI_CONNECT

Define the processing method for PMI messages.

Syntax

I_MPI_HYDRA_PMI_CONNECT=<value>

Arguments

`<value>`	The algorithm to be used
`nocache`	Do not cache `PMI` messages
`cache`	Cache `PMI` messages on the local `pmi_proxy` management processes to minimize the number of `PMI` requests. Cached information is automatically propagated to child management processes
`lazy-cache`	`cache` mode with on-demand propagation. This is the default value.
`alltoall`	Information is automatically exchanged between all `PMI_proxy` before any get request can be done

Description

Use this environment variable to select the PMI messages processing method.

I_MPI_PERHOST

Define the default settings for the -perhost option in the mpiexec and mpiexec.hydra command.

Syntax

I_MPI_PERHOST=<value>

Arguments

`<value>`	Define a value that is used for the `-perhost` option by default
`integer > 0`	Exact value for the option
`all`	All logical CPUs on the node
`allcores`	All cores (physical CPUs) on the node

Description

Set this environment variable to define the default setting for the -perhost option. The -perhost option implied with the respective value if the I_MPI_PERHOST environment variable is defined.

I_MPI_JOB_TRACE_LIBS

Choose the libraries to preload through the -trace option.

Syntax

I_MPI_JOB_TRACE_LIBS=<arg>

Deprecated Syntax

MPIEXEC_TRACE_LIBS=<arg>

Arguments

`<arg>`	String parameter
`<list>`	Blank separated list of the libraries to preload. The default value is `vt`

Description

Set this environment variable to choose an alternative library for preloading through the -trace option.

I_MPI_JOB_CHECK_LIBS

Choose the libraries to preload through the -check_mpi option.

Syntax

I_MPI_JOB_CHECK_LIBS=<arg>

Arguments

`<arg>`	String parameter
`<list>`	Blank separated list of the libraries to preload. The default value is `vtmc`

Description

Set this environment variable to choose an alternative library for preloading through the -check_mpi option.

I_MPI_HYDRA_BRANCH_COUNT

Set the hierarchical branch count.

Syntax

I_MPI_HYDRA_BRANCH_COUNT =<num>

Arguments

`<num>`	Number
`<n>` `>= 0`	The default value is `-1` if less than 128 nodes are used. This also means that there is no hierarchical structure The default value is `32` if more than 127 nodes are used

Description

Set this environment variable to restrict the number of child management processes launched by the mpiexec.hydra operation or by each pmi_proxy management process.

I_MPI_HYDRA_PMI_AGGREGATE

Turn on/off aggregation of the PMI messages.

Syntax

I_MPI_HYDRA_PMI_AGGREGATE=<arg>

Arguments

`<arg>`	Binary indicator
`enable \| yes \| on \| 1`	Enable `PMI` message aggregation. This is the default value
`disable \| no \| off \| 0`	Disable `PMI` message aggregation

Description

Set this environment variable to enable/disable aggregation of PMI messages .

I_MPI_HYDRA_GDB_REMOTE_SHELL

Set the remote shell command to run GNU* debugger.

Syntax

I_MPI_HYDRA_GDB_REMOTE_SHELL=<arg>

Arguments

`<arg>`	String parameter
`ssh`	Secure Shell (SSH). This is the default value
`rsh`	Remote shell (RSH)

Description

Set this environment variable to specify the remote shell command to run the GNU* debugger on the remote machines. You can use this environment variable to specify any shell command that has the same syntax as SSH or RSH.

I_MPI_ HYDRA_JMI_LIBRARY

Define the default setting of the JMI library.

Syntax

I_MPI_HYDRA_JMI_LIBRARY=<value>

Arguments

`<value>`	Define a string value, name, or path to `JMI` dynamic library
`libjmi_slurm.so.1.1 \| libjmi_pbs.so.1.0`	Set the library name or full path to library name. The default value is `libjmi.so`

Description

Set this environment variable to define the JMI library to be loaded by the Hydra* processor manager. Set the full path to the library if the path is not mentioned in the LD_LIBRARY_PATH environment variable. If the mpirun command is used, you do not need to set this environment variable. The JMI library is automatically detected and set.

I_MPI_HYDRA_IFACE

Set the network interface.

Syntax

I_MPI_HYDRA_IFACE=<arg>

Arguments

`<arg>`	String parameter
`<network interface>`	The network interface configured in your system

Description

Set this environment variable to specify the network interface to use. For example, use -iface ib0, if the IP emulation of your InfiniBand* network is configured on ib0.

I_MPI_HYDRA_DEMUX

Set the demultiplexer (demux) mode.

Syntax

I_MPI_HYDRA_DEMUX=<arg>

Arguments

`<arg>`	String parameter
`poll`	Set `poll` as the multiple I/O demultiplexer (`demux`) mode engine. This is the default value.
`select`	Set `select` as the multiple I/O demultiplexer (`demux`) mode engine

Description

Set this environment variable to specify the multiple I/O demux mode engine. The default is Poll.

I_MPI_HYDRA_CLEANUP

Control the creation of the default mpicleanup input file.

Syntax

I_MPI_HYDRA_CLEANUP=<value>

Arguments

`<value>`	Binary indicator
`enable \| yes \| on \| 1`	Enable the `mpicleanup` input file creation
`disable \| no \| off \| 0`	Disable the `mpicleanup` input file creation. This is the default value

Description

Set the I_MPI_HYDRA_CLEANUP environment variable to create the input file for the mpicleanup utility.

I_MPI_TMPDIR

(TMPDIR)

Set the temporary directory.

Syntax

I_MPI_TMPDIR=<arg>

Arguments

`<arg>`	String parameter
`<path>`	Set the temporary directory. The default value is `/tmp`

Description

Set this environment variable to specify the temporary directory to store the mpicleanup input file.

I_MPI_JOB_RESPECT_PROCESS_PLACEMENT

Specify whether to use the job scheduler provided process-per-node parameter.

Syntax

I_MPI_JOB_RESPECT_PROCESS_PLACEMENT=<arg>

Arguments

`<value>`	Binary indicator
`enable \| yes \| on \| 1`	Use the process placement provided by job scheduler. This is the default value
`disable \| no \| off \| 0`	Do not use the process placement provided by job scheduler

Description

If you set I_MPI_JOB_RESPECT_PROCESS_PLACEMENT=enable, then Hydra process manager uses PPN provided by job scheduler.

If you set I_MPI_JOB_RESPECT_PROCESS_PLACEMENT = disable, then Hydra process manager uses PPN provided in command line option or using I_MPI_PERHOST environment variable.

I_MPI_GTOOL

Specify the tools to be launched for selected ranks.

Syntax

I_MPI_GTOOL=“<command line for a tool 1>:<ranks set 1>[=exclusive][@arch 1]; <command line for a tool 2>:<ranks set 2>[=exclusive][@arch 2]; … ;<command line for a tool n>:<ranks set n>[=exclusive][@arch n]”

Arguments

`<arg>`	Parameters
`<command line for a tool>`	Specify a tool along with its parameters
`<rank set>`	Specify the ranks range which will be involved in the tool execution. Ranks are separated with a comma or “`-`” symbol can be used for a set of contiguous ranks. Note: If you specify incorrect rank index, the corresponding warning is printed and a tool continues working for valid ranks.
[=exclusive]	Specify this parameter to prevent launching a tool for more than one rank per host. This parameter is optional.
`[@arch]`	Specify the architecture on which a tool will apply. That means that for a given `<rank set>`, the tool is only applied for those ranks which have been allocated on hosts with the specific architecture. This parameter is optional. For the values of`[@arch]`, see the argument table of I_MPI_PLATFORM for the detail value descriptions. If you launch the debugger on Intel® Xeon Phi™ coprocessor, setting `[@arch]` is required. See examples for details.

Description

Use this option to launch the tools such as Intel® VTune™ Amplifier XE, Valgrind*, and GNU* Debugger on specified ranks.

Examples:

The following command examples demonstrate different scenarios of using the I_MPI_GTOOL environment variable:

Launch Intel® VTune™ Amplifier XE and Valgrind* by setting the I_MPI_GTOOL environment variable:

$ export I_MPI_GTOOL=“amplxe-cl –collect advanced-hotspots –analyze-system –r result1:5,3,7-9=exclusive@nhm;valgrind –log-file=log_%p :0,1,10-12@wsm”

$ mpiexec.hydra –n 16 a.out

Use this command to apply amplxe-cl to a rank with a minimal index allocated on the hosts in Intel® microarchitecture code name Nehalem from the given rank set. At the same time Valgrind* is applied for all ranks allocated on the hosts in Intel® microarchitecture code name Westmere from the specified rank set. Valgrind results are written to files with names log_<process ID>.
Launch GNU* Debugger (GDB*) by setting the I_MPI_GTOOL environment variable:

$ mpiexec.hydra –n 16 –genv I_MPI_GTOOL=“gdb:3,5,7-9” a.out

Use this command to apply gdb to the given rank set.

Note:

The options and the environment variable –gtool, -gtoolfile and I_MPI_GTOOL are mutually exclusive. The options –gtool and –gtoolfile are of the same priority. The first specified option in a command line is effective and the second specified option is ignored. Both –gtool and -gtoolfile options have higher priority than the I_MPI_GTOOL environment variable. Thus, use the I_MPI_GTOOL environment variable if you have not specified neither –gtool or –gtoolfile options in the mpiexec.hydra command.