The "--allow-run-as-root" option
================================

Allow execution as root **(STRONGLY DISCOURAGED)**.

Running as root exposes the user to potentially catastrophic file
system corruption and damage — e.g., if the user accidentally points
the root of the session directory to a system required point, this
directory and all underlying elements will be deleted upon job
completion, thereby rendering the system inoperable.

It is recognized that some environments (e.g., containers) may require
operation as root, and that the user accepts the risks in those
scenarios. Accordingly, one can override PRRTE's run-as-root
protection by providing one of the following:

* The "--allow-run-as-root" command line directive

* Adding **BOTH** of the following environmental parameters:

     * "PRTE_ALLOW_RUN_AS_ROOT=1"

     * "PRTE_ALLOW_RUN_AS_ROOT_CONFIRM=1"

Again, we recommend this only be done if absolutely necessary.


The "--bind-to" option
======================

By default, processes are bound to individual CPUs (either COREs or
HWTHREADs, as defined by default or by user specification for the
job). On nodes that are OVERSUBSCRIBEd (i.e., where the number of
procs exceeds the number of assigned slots), the default is to not
bind the processes.

Note:

  Processes from prior jobs that are already executing on a node are
  not "unbound" when a new job mapping results in the node becoming
  oversubscribed.

Binding is performed to the first available specified object type
within the object where the process was mapped. In other words,
binding can only be done to the mapped object or to a resource located
beneath that object.

An object is considered completely consumed when the number of
processes bound to it equals the number of CPUs within it. Unbound
processes are not considered in this computation. Additional processes
cannot be mapped to consumed objects unless the "OVERLOAD" qualifier
is provided via the "--bind-to" command line option.

Note that directives and qualifiers are case-insensitive and can be
shortened to the minimum number of characters to uniquely identify
them. Thus, "L1CACHE" can be given as "l1cache" or simply as "L1".

Supported binding directives include:

* "NONE" does not bind the processes

* "HWTHREAD" binds each process to a single hardware thread/ This
  requires that hwthreads be treated as independent CPUs (i.e., that
  either the "HWTCPUS" qualifier be provided to the "map-by" option or
  that "hwthreads" be designated as CPUs by default).

* "CORE" binds each process to a single core. This can be done whether
  "hwthreads" or "cores" are being treated as independent CPUs
  provided that mapping is performed at the core or higher level.

* "L1CACHE" binds each process to all the CPUs in an "L1" cache.

* "L2CACHE" binds each process to all the CPUs in an "L2" cache

* "L3CACHE" binds each process to all the CPUs in an "L3" cache

* "NUMA" binds each process to all the CPUs in a "NUMA" region

* "PACKAGE" binds each process to all the CPUs in a "PACKAGE"

Any directive can include qualifiers by adding a colon (:) and any
combination of one or more of the following to the "--bind-to" option:

* "OVERLOAD" indicates that objects can have more processes bound to
  them than CPUs within them

* "IF-SUPPORTED" indicates that the job should continue to be launched
  and executed even if binding cannot be performed as requested.

Note:

  Directives and qualifiers are case-insensitive. "OVERLOAD" is the
  same as "overload".


The "--debug-daemons" option
============================

Debug daemon output enabled. This is a somewhat limited stream of
information normally used to simply confirm that the daemons started.
Includes leaving the output streams open.


The "--debug-daemons-file" option
=================================

Debug daemon output is enabled and all output from the daemons is
redirected into files with names of the form:

   output-prted-<daemon-nspace>-<nodename>.log

These names avoid conflict on shared file systems. The files are
located in the top-level session directory assigned to the DVM.


The "--display" option
======================

The "display" command line directive must be accompanied by a comma-
delimited list of case-insensitive options indicating what information
about the job and/or allocation is to be displayed. The full directive
need not be provided — only enough characters are required to uniquely
identify the directive. For example, "ALL" is sufficient to represent
the "ALLOCATION" directive — while "MAP" can not be used to represent
"MAP-DEVEL" (though "MAP-D" would suffice).

Supported values include:

* "ALLOCATION" displays the detected hosts and slot assignments for
  this job

* "BINDINGS" displays the resulting bindings applied to processes in
  this job

* "MAP" displays the resulting locations assigned to processes in this
  job

* "MAP-DEVEL" displays a more detailed report on the locations
  assigned to processes in this job that includes local and node
  ranks, assigned bindings, and other data

* "TOPO=LIST" displays the topology of each node in the semicolon-
  delimited list that is allocated to the job

* "CPUS[=LIST]" displays the available CPUs on the provided semicolon-
  delimited list of nodes (defaults to all nodes)

The display command line directive can include qualifiers by adding a
colon (":") and any combination of one or more of the following
(delimited by colons):

* "PARSEABLE" directs that the output be provided in a format that is
  easily parsed by machines. Note that "PARSABLE" is also accepted as
  a typical spelling for the qualifier.

Provided qualifiers will apply to *all* of the display directives.


The "--dvm" option
==================

A required argument is passed to the "--dvm" directive to specify the
location of the DVM controller (e.g., "--dvm pid:12345") or by passing
the string "search" to instead search for an existing controller.

Supported options include:

* "search": directs the tool to search for available DVM controllers
  it is authorized to use, connecting to the first such candidate it
  finds.

* "pid:<arg>": provides the PID of the target DVM controller. This can
  be given as either the PID itself (arg = int) or the path to a file
  that contains the PID (arg = "file:<path>")

* "file:<path>": provides the path to a PMIx rendezvous file that is
  output by PMIx servers — the file contains all the required
  information for completing the connection

* "uri:<arg>": specifies the URI of the DVM controller, or the name of
  the file (specified as "file:filename") that contains that info

* "ns:<arg>": specifies the namespace of the DVM controller

* "system": exclusively find and use the system-level DVM controller

* "system-first": look for a system-level DVM controller, fall back to
  searching for an available DVM controller the command is authorized
  to use if a system-level controller is not found

Examples:

   prterun --dvm file:dvm_uri.txt --np 4 ./a.out

   prterun --dvm pid:12345 --np 4 ./a.out

   prterun --dvm uri:file:dvm_uri.txt --np 4 ./a.out

   prterun --dvm ns:prte-node1-2095 --np 4 ./a.out

   prterun --dvm pid:file:prte_pid.txt --np 4 ./a.out

   prterun --dvm search --np 4 ./a.out


The "--dvm-hostfile" option
===========================

PRRTE supports several levels of user-specified host lists based on an
established precedence order. Users can specify a default hostfile
that contains a list of nodes to be used by the DVM. Only one default
hostfile can be provided for a given DVM. In addition, users can
specify a hostfile that contains a list of nodes to be used for a DVM,
or can provide a comma-delimited list of nodes to be used for that DVM
via the "--host" command line option.

The precedence order applied to these various options depends to some
extent on the local environment. The following table illustrates how
host and hostfile directives work together to define the set of hosts
upon which a DVM will execute in the absence of a resource manager
(RM):

+------------+---------+------------+----------------------------------+
| Default    | host    | hostfile   | Result                           |
| hostfile   |         |            |                                  |
|============|=========|============|==================================|
| unset      | unset   | unset      | The DVN will consist solely of   |
|            |         |            | the local host where the DVM was |
|            |         |            | started.                         |
+------------+---------+------------+----------------------------------+
| unset      | set     | unset      | Host option defines resource     |
|            |         |            | list for the DVM.                |
+------------+---------+------------+----------------------------------+
| unset      | unset   | set        | Hostfile option defines resource |
|            |         |            | list for the DVM.                |
+------------+---------+------------+----------------------------------+
| unset      | set     | set        | Hostfile option defines resource |
|            |         |            | list for the DVM, then host      |
|            |         |            | filters the list to define the   |
|            |         |            | final set of nodes to be used by |
|            |         |            | the DVM                          |
+------------+---------+------------+----------------------------------+
| set        | unset   | unset      | Default hostfile defines         |
|            |         |            | resource list for the DVM        |
+------------+---------+------------+----------------------------------+
| set        | set     | unset      | Default hostfile defines         |
|            |         |            | resource list for the DVM, then  |
|            |         |            | host filters the list to define  |
|            |         |            | the final set of nodes to be     |
|            |         |            | used by the DVM                  |
+------------+---------+------------+----------------------------------+
| set        | set     | set        | Default hostfile defines         |
|            |         |            | resource list for the DVM, then  |
|            |         |            | hostfile filters the list, and   |
|            |         |            | then host filters the list to    |
|            |         |            | define the final set of nodes to |
|            |         |            | be used by the DVM               |
+------------+---------+------------+----------------------------------+

This changes somewhat in the presence of an RM as that entity
specifies the initial allocation of nodes. In this case, the default
hostfile, hostfile and host directives are all used to filter the RM's
specification so that a user can utilize different portions of the
allocation for different DVMs. This is done according to the same
precedence order as in the prior table, with the RM providing the
initial pool of nodes.


The "--forward-signals" option
==============================

Comma-delimited list of additional signals (names or integers) to
forward to application processes ("none" = forward nothing). Signals
provided by default include SIGTSTP, SIGUSR1, SIGUSR2, SIGABRT,
SIGALRM, and SIGCONT.


The "--host" option
===================

Host syntax consists of a comma-delimited list of node names, each
entry optionally containing a ":N" extension indicating the number of
slots to assign to that entry:

   --host node01:5,node02

In the absence of the slot extension, one slot will be assigned to the
node. Duplicate entries are aggregated and the number of slots
assigned to that node are summed together.

Note:

  A "slot" is the PRRTE term for an allocatable unit where we can
  launch a process. Thus, the number of slots equates to the maximum
  number of processes PRRTE may start on that node without
  oversubscribing it.


The "--launcher-hostfile" option
================================

PRRTE supports several levels of user-specified hostfiles based on an
established precedence order. Users can specify a hostfile that
contains a list of nodes to be used for the job, or can provide a
comma-delimited list of nodes to be used for that job via the "--host"
command line option.

The precedence order applied to these various options depends to some
extent on the local environment. The following table illustrates how
host and hostfile directives work together to define the set of hosts
upon which a DVM will execute the job in the absence of a resource
manager (RM):

+---------+------------+-----------------------------------------------+
| host    | hostfile   | Result                                        |
|=========|============|===============================================|
| unset   | unset      | The DVM will utilize all its available        |
|         |            | resources when mapping the job.               |
+---------+------------+-----------------------------------------------+
| set     | unset      | Host option defines resource list for the job |
+---------+------------+-----------------------------------------------+
| unset   | set        | Hostfile defines resource list for the job    |
+---------+------------+-----------------------------------------------+
| set     | set        | Hostfile defines resource list for the job,   |
|         |            | then host filters the list to define the      |
|         |            | final set of nodes to be used for the job     |
+---------+------------+-----------------------------------------------+


The "--leave-session-attached" option
=====================================

Do not discard stdout/stderr of remote PRRTE daemons. The primary use
for this option is to ensure that the daemon output streams (i.e.,
stdout and stderr) remain open after launch, thus allowing the user to
see any daemon-generated error messages. Otherwise, the daemon will
"daemonize" itself upon launch, thereby closing its output streams.


The "--map-by" option
=====================

Processes are mapped based on one of the following directives as
applied at the job level:

* "SLOT" assigns procs to each node up to the number of available
  slots on that node before moving to the next node in the allocation

* "HWTHREAD" assigns a proc to each hardware thread on a node in a
  round-robin manner up to the number of available slots on that node
  before moving to the next node in the allocation

* "CORE" (default) assigns a proc to each core on a node in a round-
  robin manner up to the number of available slots on that node before
  moving to the next node in the allocation

* "L1CACHE" assigns a proc to each L1 cache on a node in a round-robin
  manner up to the number of available slots on that node before
  moving to the next node in the allocation

* "L2CACHE" assigns a proc to each L2 cache on a node in a round-robin
  manner up to the number of available slots on that node before
  moving to the next node in the allocation

* "L3CACHE" assigns a proc to each L3 cache on a node in a round-robin
  manner up to the number of available slots on that node before
  moving to the next node in the allocation

* "NUMA" assigns a proc to each NUMA region on a node in a round-robin
  manner up to the number of available slots on that node before
  moving to the next node in the allocation

* "PACKAGE" assigns a proc to each package on a node in a round-robin
  manner up to the number of available slots on that node before
  moving to the next node in the allocation

* "NODE" assigns processes in a round-robin fashion to all nodes in
  the allocation, with the number assigned to each node capped by the
  number of available slots on that node

* "SEQ" (often accompanied by the file=<path> qualifier) assigns one
  process to each node specified in the file. The sequential file is
  to contain an entry for each desired process, one per line of the
  file.

* "PPR:N":resource maps N procs to each instance of the specified
  resource type in the allocation

* "RANKFILE" (often accompanied by the file=<path> qualifier) assigns
  one process to the node/resource specified in each entry of the
  file, one per line of the file.

* "PE-LIST=a,b" assigns procs to each node in the allocation based on
  the ORDERED qualifier. The list is comprised of comma-delimited
  ranges of CPUs to use for this job. If the ORDERED qualifier is not
  provided, then each node will be assigned procs up to the number of
  available slots, capped by the availability of the specified CPUs.
  If ORDERED is given, then one proc will be assigned to each of the
  specified CPUs, if available, capped by the number of slots on each
  node and the total number of specified processes. Providing the
  OVERLOAD qualifier to the "bind-to" option removes the check on
  availability of the CPU in both cases.

Any directive can include qualifiers by adding a colon (":") and any
combination of one or more of the following (delimited by colons) to
the "--map-by" option (except where noted):

* "PE=n" bind n CPUs to each process (can not be used in combination
  with rankfile or pe-list directives)

* "SPAN" load balance the processes across the allocation by treating
  the allocation as a single "super-node" (can not be used in
  combination with "slot", "node", "seq", "ppr", "rankfile", or "pe-
  list" directives)

* "OVERSUBSCRIBE" allow more processes on a node than processing
  elements

* "NOOVERSUBSCRIBE" means "!OVERSUBSCRIBE"

* "NOLOCAL" do not launch processes on the same node as "prun"

* "HWTCPUS" use hardware threads as CPU slots

* "CORECPUS" use cores as CPU slots (default)

* "INHERIT" indicates that a child job (i.e., one spawned from within
  an application) shall inherit the placement policies of the parent
  job that spawned it.

* "NOINHERIT" means "`!INHERIT"

* "FILE=<path>" (path to file containing sequential or rankfile
  entries).

* "ORDERED" only applies to the "PE-LIST" option to indicate that
  procs are to be bound to each of the specified CPUs in the order in
  which they are assigned (i.e., the first proc on a node shall be
  bound to the first CPU in the list, the second proc shall be bound
  to the second CPU, etc.)

Note:

  Directives and qualifiers are case-insensitive and can be shortened
  to the minimum number of characters to uniquely identify them. Thus,
  "L1CACHE" can be given as "l1cache" or simply as "L1".

The type of CPU (core vs hwthread) used in the mapping algorithm is
determined as follows:

* by user directive on the command line via the HWTCPUS qualifier to
  the "--map-by" directive

* by setting the "rmaps_default_mapping_policy" MCA parameter to
  include the "HWTCPUS" qualifier. This parameter sets the default
  value for a PRRTE DVM — qualifiers are carried across to DVM jobs
  started via "prun" unless overridden by the user's command line

* defaults to CORE in topologies where core CPUs are defined, and to
  hwthreads otherwise.

If your application uses threads, then you probably want to ensure
that you are either not bound at all (by specifying "--bind-to none"),
or bound to multiple cores using an appropriate binding level or
specific number of processing elements per application process via the
"PE=#" qualifier to the "--map-by" command line directive.

A more detailed description of the mapping, ranking, and binding
procedure can be obtained via the "--help placement" option.


The "--output" option
=====================

The "output" command line directive must be accompanied by a comma-
delimited list of case-insensitive options that control how output is
generated. The full directive need not be provided — only enough
characters are required to uniquely identify the directive. For
example, "MERGE" is sufficient to represent the "MERGE-STDERR-TO-
STDOUT" directive — while "TAG" can not be used to represent "TAG-
DETAILED" (though "TAG-D" would suffice).

Supported values include:

* "TAG" marks each output line with the "[job,rank]<stream>:" of the
  process that generated it

* "TAG-DETAILED" marks each output line with a detailed annotation
  containing "[namespace,rank][hostname:pid]<stream>:" of the process
  that generated it

* "TAG-FULLNAME" marks each output line with the
  "[namespace,rank]<stream>:" of the process that generated it

* "TAG-FULLNAME" marks each output line with the
  "[namespace,rank]<stream>:" of the process that generated it

* "TIMESTAMP" prefixes each output line with a "[datetime]<stream>:"
  stamp. Note that the timestamp will be the time when the line is
  output by the DVM and not the time when the source output it

* "XML" provides all output in a pseudo-XML format "MERGE-STDERR-TO-
  STDOUT" merges stderr into stdout

* "DIR=DIRNAME" redirects output from application processes into
  "DIRNAME/job/rank/std[out,err,diag]". The provided name will be
  converted to an absolute path

* "FILE=FILENAME" redirects output from application processes into
  "filename.rank." The provided name will be converted to an absolute
  path

Supported qualifiers include "NOCOPY" (do not copy the output to the
stdout/err streams), and "RAW" (do not buffer the output into complete
lines, but instead output it as it is received).


The "--personality" option
==========================

Specify the personality to be used. This governs selection of the
plugin responsible for defining and parsing the command line,
harvesting and forwarding environmental variables, and providing
library-dependent support to the launched processes. Examples include
"ompi" for an application compiled with Open MPI, "mpich" for one
built against the MPICH library, or "oshmem" for an OpenSHMEM
application compiled against SUNY's reference library.


The "--pmixmca" option
======================

Pass a PMIx MCA parameter

Syntax: "--pmixmca <key> <value>", where "key" is the parameter name
and "value" is the parameter value.


The "--prefix" option
=====================

Prefix to be used to look for PRRTE executables. PRRTE automatically
sets the prefix for remote daemons if it was either configured with
the "--enable-prte-prefix-by-default" option OR prte itself was
executed with an absolute path to the prte command. This option
overrides those settings, if present, and forces use of the provided
path.


The "--prtemca" option
======================

Pass a PRRTE MCA parameter.

Syntax: "--prtemca <key> <value>", where "key" is the parameter name
and "value" is the parameter value.


The "--noprefix" option
=======================

Disable automatic "--prefix" behavior. PRRTE automatically sets the
prefix for remote daemons if it was either configured with the "--
enable-prte-prefix-by-default" option OR prte itself was executed with
an absolute path to the "prte" command. This option disables that
behavior.


The "--rank-by" option
======================

PRRTE automatically ranks processes for each job starting from zero.
Regardless of the algorithm used, rank assignments span applications
in the same job — i.e., a command line of

   -n 3 app1 : -n 2 app2

will result in "app1" having three processes ranked 0-2 and "app2"
having two processes ranked 3-4.

By default, process ranks are assigned in accordance with the mapping
directive — e.g., jobs that are mapped by-node will have the process
ranks assigned round-robin on a per-node basis. However, users can
override the default by specifying any of the following directives
using the "--rank-by" command line option:

* "SLOT" assigns ranks to each process on a node in the order in which
  the mapper assigned them. This is the default behavior, but is
  provided as an explicit option to allow users to override any
  alternative default specified in the environment. When mapping to a
  specific resource type, procs assigned to a given instance of that
  resource on a node will be ranked on a per-resource basis on that
  node before moving to the next node.

* "NODE" assigns ranks round-robin on a per-node basis

* "FILL" assigns ranks to procs mapped to a particular resource type
  on each node, filling all ranks on that resource before moving to
  the next resource on that node. For example, procs mapped by
  "L1cache" would have all procs on the first "L1cache" ranked
  sequentially before moving to the second "L1cache" on the node. Once
  all procs on the node have been ranked, ranking would continue on
  the next node.

* "SPAN" assigns ranks round-robin to procs mapped to a particular
  resource type, treating the collection of resource instances
  spanning the entire allocation as a single "super node" before
  looping around for the next pass. Thus, ranking would begin with the
  first proc on the first "L1cache" on the first node, then the next
  rank would be assigned to the first proc on the second "L1cache" on
  that node, proceeding across until the first proc had been ranked on
  all "L1cache" used by the job before circling around to rank the
  second proc on each object.

The "rank-by" command line option has no qualifiers.

Note:

  Directives are case-insensitive.  "SPAN" is the same as "span".

A more detailed description of the mapping, ranking, and binding
procedure can be obtained via the "--help placement" option.


The "--runtime-options" option
==============================

The "--runtime-options" command line directive must be accompanied by
a comma-delimited list of case-insensitive options that control the
runtime behavior of the job. The full directive need not be provided —
only enough characters are required to uniquely identify the
directive.

Runtime options are typically "true" or "false", though this is not a
requirement on developers. Since the value of each option may need to
be set (e.g., to override a default set by MCA parameter), the syntax
of the command line directive includes the use of an "=" character to
allow inclusion of a value for the option. For example, one can set
the "ABORT-NONZERO-STATUS" option to "true" by specifying it as
"ABORT-NONZERO-STATUS=1". Note that boolean options can be set to
"true" using a non-zero integer or a case-insensitive string of the
word "true".  For the latter representation, the user need only
provide at least the "T" character. The same policy applies to setting
a boolean option to "false".

Note that a boolean option will default to "true" if provided without
a value. Thus, "--runtime-options abort-nonzero" is sufficient to set
the "ABORT-NONZERO-STATUS" option to "true".

Supported values include:

* "ERROR-NONZERO-STATUS[=(bool)]": if set to false, this directs the
  runtime to treat a process that exits with non-zero status as a
  normal termination.  If set to true, the runtime will consider such
  an occurrence as an error termination and take appropriate action —
  i.e., the job will be terminated unless a runtime option directs
  otherwise. This option defaults to a true value if the option is
  given without a value.

* "DONOTLAUNCH": directs the runtime to map but not launch the
  specified job. This is provided to help explore possible process
  placement patterns before actually starting execution. No value need
  be passed as this is not an option that can be set by default in
  PRRTE.

* "SHOW-PROGRESS[=(bool)]": requests that the runtime provide progress
  reports on its startup procedure — i.e., the launch of its daemons
  in support of a job. This is typically used to debug DVM startup on
  large systems.  This option defaults to a true value if the option
  is given without a value.

* "NOTIFYERRORS[=(bool)]": if set to true, requests that the runtime
  provide a PMIx event whenever a job encounters an error — e.g., a
  process fails.  The event is to be delivered to each remaining
  process in the job. This option defaults to a true value if the
  option is given without a value.  See "--help notifications" for
  more detail as to the PMIx event codes available for capturing
  failure events.

* "RECOVERABLE[=(bool)]": if set to true, this indicates that the
  application wishes to consider the job as recoverable — i.e., the
  application is assuming responsibility for recovering from any
  process failure. This could include application-driven spawn of a
  substitute process or internal compensation for the missing process.
  This option defaults to a true value if the option is given without
  a value.

* "AUTORESTART[=(bool)]": if set to true, this requests that the
  runtime automatically restart failed processes up to "max restarts"
  number of times. This option defaults to a true value if the option
  is given without a value.

* "CONTINUOUS[=(bool)]": if set to true, this informs the runtime that
  the processes in this job are to run until explicitly terminated.
  Processes that fail are to be automatically restarted up to "max
  restarts" number of times. Notification of process failure is to be
  delivered to all processes in the application. This is the
  equivalent of specifying "RECOVERABLE", "NOTIFYERRORS", and
  "AUTORESTART" options except that the runtime, not the application,
  assumes responsibility for process recovery. This option defaults to
  a true value if the option is given without a value.

* "MAX-RESTARTS=<int>": indicates the maximum number of times a given
  process is to be restarted. This can be set at the application or
  job level (which will then apply to all applications in that job).

* "EXEC-AGENT=<path>" indicates the executable that shall be used to
  start an application process. The resulting command for starting an
  application process will be "<path> app <app-argv>". The path may
  contain its own command line arguments.

* "DEFAULT-EXEC-AGENT": directs the runtime to use the system default
  exec agent to start an application process. No value need be passed
  as this is not an option that can be set by default in PRRTE.

* "OUTPUT-PROCTABLE[(=channel)]": directs the runtime to report the
  convential debugger process table (includes PID and host location of
  each process in the application). Output is directed to stdout if
  the channel is "-", stderr if "+", or into the specified file
  otherwise. If no channel is specified, output will be directed to
  stdout.

* "STOP-ON-EXEC": directs the runtime to stop the application
  process(es) immediately upon exec'ing them. The directive will apply
  to all processes in the job.

* "STOP-IN-INIT": indicates that the runtime should direct the
  application process(es) to stop in "PMIx_Init()". The directive will
  apply to all processes in the job.

* "STOP-IN-APP": indicates that the runtime should direct application
  processes to stop at some application-defined place and notify they
  are ready-to-debug. The directive will apply to all processes in the
  job.

* "TIMEOUT=<string>": directs the runtime to terminate the job after
  it has executed for the specified time. Time is specified in colon-
  delimited format — e.g., "01:20:13:05" to indicate 1 day, 20 hours,
  13 minutes and 5 seconds. Time specified without colons will be
  assumed to have been given in seconds.

* "SPAWN-TIMEOUT=<string>": directs the runtime to terminate the job
  if job launch is not completed within the specified time. Time is
  specified in colon-delimited format — e.g., "01:20:13:05" to
  indicate 1 day, 20 hours, 13 minutes and 5 seconds.  Time specified
  without colons will be assumed to have been given in seconds.

* "REPORT-STATE-ON-TIMEOUT[(=bool)]": directs the runtime to provide a
  detailed report on job and application process state upon job
  timeout. This option defaults to a true value if the option is given
  without a value.

* "GET-STACK-TRACES[(=bool)]": requests that the runtime provide stack
  traces on all application processes still executing upon timeout.
  This option defaults to a true value if the option is given without
  a value.

* "REPORT-CHILD-JOBS-SEPARATELY[(=bool)]": directs the runtime to
  report the exit status of any child jobs spawned by the primary job
  separately. If false, then the final exit status reported will be
  zero if the primary job and all spawned jobs exit normally, or the
  first non-zero status returned by either primary or child jobs. This
  option defaults to a true value if the option is given without a
  value.

* "AGGREGATE-HELP-MESSAGES[(=bool)]": directs the runtime to aggregate
  help messages, reporting each unique help message once accompanied
  by the number of processes that reported it. This option defaults to
  a true value if the option is given without a value.

* "FWD-ENVIRONMENT[(=bool)]": directs the runtime to forward the
  entire local environment in support of the application. This option
  defaults to a true value if the option is given without a value.

The "--runtime-options" command line option has no qualifiers.

Note:

  Directives are case-insensitive.  "FWD-ENVIRONMENT" is the same as
  "fwd-environment".


The "--stream-buffering" option
===============================

Adjust buffering for stdout/stderr.  Allowable values:

* 0: unbuffered

* 1: line buffered

* 2: fully buffered


The "--tune" option
===================

Comma-delimited list of one or more files containing PRRTE and PMIx
MCA params for tuning DVM and/or application operations. Parameters in
the file will be treated as *generic* parameters and subject to the
translation rules/uncertainties.  See "--help mca" for more
information.

Syntax in the file is:

   param = value

with one parameter and its associated value per line. Empty lines and
lines beginning with the "#" character are ignored.


The "-x" option
===============

Export an environment variable, optionally specifying a value. For
example:

* "-x foo" exports the environment variable "foo" and takes its value
  from the current environment.

* "-x foo=bar" exports the environment variable name "foo" and sets
  its value to "bar" in the started processes.

* "-x foo*" exports all current environmental variables starting with
  "foo".
