Ubuntu Manpage: salloc - Obtain a Slurm job allocation (a set of nodes), execute a command, and then release the

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Provided by: slurm-client_15.08.7-1build1_amd64

NAME

       salloc  -  Obtain  a  Slurm  job  allocation  (a  set  of nodes), execute a command, and then release the
       allocation when the command is finished.

SYNOPSIS

       salloc [options] [<command> [command args]]

DESCRIPTION

       salloc is used to allocate a Slurm job allocation, which is a set of  resources  (nodes),  possibly  with
       some  set  of  constraints  (e.g.  number  of processors per node).  When salloc successfully obtains the
       requested allocation, it then runs the command specified by the user.  Finally, when the  user  specified
       command is complete, salloc relinquishes the job allocation.

       The  command  may  be  any  program  the  user  wishes.   Some typical commands are xterm, a shell script
       containing srun commands, and srun (see the EXAMPLES section). If no command is specified, then the value
       of  SallocDefaultCommand  in slurm.conf is used. If SallocDefaultCommand is not set, then salloc runs the
       user's default shell.

       The following document describes the the influence of various options on the allocation of cpus  to  jobs
       and tasks.
       http://slurm.schedmd.com/cpu_management.html

       NOTE: The salloc logic includes support to save and restore the terminal line settings and is designed to
       be executed in the foreground. If you need to execute salloc in the background, set its standard input to
       some file, for example: "salloc -n16 a.out </dev/null &"

OPTIONS

-A, --account=<account>
Charge resources used by this job to specified account. The account is an arbitrary string. The
account name may be changed after job submission using the scontrol command.

--acctg-freq
Define the job accounting and profiling sampling intervals. This can be used to override the
JobAcctGatherFrequency parameter in Slurm's configuration file, slurm.conf. The supported format
is as follows:

--acctg-freq=<datatype>=<interval>
where <datatype>=<interval> specifies the task sampling interval for the
jobacct_gather plugin or a sampling interval for a profiling type by the
acct_gather_profile plugin. Multiple, comma-separated <datatype>=<interval> intervals
may be specified. Supported datatypes are as follows:

task=<interval>
where <interval> is the task sampling interval in seconds for the
jobacct_gather plugins and for task profiling by the acct_gather_profile
plugin. NOTE: This frequency is used to monitor memory usage. If memory limits
are enforced the highest frequency a user can request is what is configured in
the slurm.conf file. They can not turn it off (=0) either.

energy=<interval>
where <interval> is the sampling interval in seconds for energy profiling using
the acct_gather_energy plugin

network=<interval>
where <interval> is the sampling interval in seconds for infiniband profiling
using the acct_gather_infiniband plugin.

filesystem=<interval>
where <interval> is the sampling interval in seconds for filesystem profiling
using the acct_gather_filesystem plugin.

The default value for the task sampling interval
is 30. The default value for all other intervals is 0. An interval of 0 disables sampling of the
specified type. If the task sampling interval is 0, accounting information is collected only at
job termination (reducing Slurm interference with the job).
Smaller (non-zero) values have a greater impact upon job performance, but a value of 30 seconds is
not likely to be noticeable for applications having less than 10,000 tasks.

-B --extra-node-info=<sockets[:cores[:threads]]>
Request a specific allocation of resources with details as to the number and type of computational
resources within a cluster: number of sockets (or physical processors) per node, cores per socket,
and threads per core. The total amount of resources being requested is the product of all of the
terms. Each value specified is considered a minimum. An asterisk (*) can be used as a
placeholder indicating that all available resources of that type are to be utilized. As with
nodes, the individual levels can also be specified in separate options if desired:
--sockets-per-node=<sockets>
--cores-per-socket=<cores>
--threads-per-core=<threads>
If SelectType is configured to select/cons_res, it must have a parameter of CR_Core,
CR_Core_Memory, CR_Socket, or CR_Socket_Memory for this option to be honored. This option is not
supported on BlueGene systems (select/bluegene plugin is configured). If not specified, the
scontrol show job will display 'ReqS:C:T=*:*:*'.

--bb=<spec>
Burst buffer specification. The form of the specification is system dependent.

--begin=<time>
Submit the batch script to the Slurm controller immediately, like normal, but tell the controller
to defer the allocation of the job until the specified time.

Time may be of the form HH:MM:SS to run a job at a specific time of day (seconds are optional).
(If that time is already past, the next day is assumed.) You may also specify midnight, noon,
fika (3 PM) or teatime (4 PM) and you can have a time-of-day suffixed with AM or PM for running in
the morning or the evening. You can also say what day the job will be run, by specifying a date
of the form MMDDYY or MM/DD/YY YYYY-MM-DD. Combine date and time using the following format
YYYY-MM-DD[THH:MM[:SS]]. You can also give times like now + count time-units, where the time-units
can be seconds (default), minutes, hours, days, or weeks and you can tell Slurm to run the job
today with the keyword today and to run the job tomorrow with the keyword tomorrow. The value may
be changed after job submission using the scontrol command. For example:
--begin=16:00
--begin=now+1hour
--begin=now+60 (seconds by default)
--begin=2010-01-20T12:34:00

Notes on date/time specifications:
- Although the 'seconds' field of the HH:MM:SS time specification is allowed by the code, note
that the poll time of the Slurm scheduler is not precise enough to guarantee dispatch of the job
on the exact second. The job will be eligible to start on the next poll following the specified
time. The exact poll interval depends on the Slurm scheduler (e.g., 60 seconds with the default
sched/builtin).
- If no time (HH:MM:SS) is specified, the default is (00:00:00).
- If a date is specified without a year (e.g., MM/DD) then the current year is assumed, unless
the combination of MM/DD and HH:MM:SS has already passed for that year, in which case the next
year is used.

--bell Force salloc to ring the terminal bell when the job allocation is granted (and only if stdout is a
tty). By default, salloc only rings the bell if the allocation is pending for more than ten
seconds (and only if stdout is a tty). Also see the option --no-bell.

--comment=<string>
An arbitrary comment.

-C, --constraint=<list>
Nodes can have features assigned to them by the Slurm administrator. Users can specify which of
these features are required by their job using the constraint option. Only nodes having features
matching the job constraints will be used to satisfy the request. Multiple constraints may be
specified with AND, OR, matching OR, resource counts, etc. Supported constraint options include:

Single Name
Only nodes which have the specified feature will be used. For example,
--constraint="intel"

Node Count
A request can specify the number of nodes needed with some feature by appending an asterisk
and count after the feature name. For example "--nodes=16 --constraint=graphics*4 ..."
indicates that the job requires 16 nodes and that at least four of those nodes must have
the feature "graphics."

AND If only nodes with all of specified features will be used. The ampersand is used for an
AND operator. For example, --constraint="intel&gpu"

OR If only nodes with at least one of specified features will be used. The vertical bar is
used for an OR operator. For example, --constraint="intel|amd"

Matching OR
If only one of a set of possible options should be used for all allocated nodes, then use
the OR operator and enclose the options within square brackets. For example:
"--constraint=[rack1|rack2|rack3|rack4]" might be used to specify that all nodes must be
allocated on a single rack of the cluster, but any of those four racks can be used.

Multiple Counts
Specific counts of multiple resources may be specified by using the AND operator and
enclosing the options within square brackets. For example:
"--constraint=[rack1*2&rack2*4]" might be used to specify that two nodes must be allocated
from nodes with the feature of "rack1" and four nodes must be allocated from nodes with the
feature "rack2".

--contiguous
If set, then the allocated nodes must form a contiguous set. Not honored with the topology/tree
or topology/3d_torus plugins, both of which can modify the node ordering.

--cores-per-socket=<cores>
Restrict node selection to nodes with at least the specified number of cores per socket. See
additional information under -B option above when task/affinity plugin is enabled.

--cpu-freq =<p1[-p2[:p3]]>

Request that job steps initiated by srun commands inside this allocation be run at some requested
frequency if possible, on the CPUs selected for the step on the compute node(s).

p1 can be [#### | low | medium | high | highm1] which will set the frequency scaling_speed to the
corresponding value, and set the frequency scaling_governor to UserSpace. See below for definition
of the values.

p1 can be [Conservative | OnDemand | Performance | PowerSave] which will set the scaling_governor
to the corresponding value. The governor has to be in the list set by the slurm.conf option
CpuFreqGovernors.

When p2 is present, p1 will be the minimum scaling frequency and p2 will be the maximum scaling
frequency.

p2 can be [#### | medium | high | highm1] p2 must be greater than p1.

p3 can be [Conservative | OnDemand | Performance | PowerSave | UserSpace] which will set the
governor to the corresponding value.

If p3 is UserSpace, the frequency scaling_speed will be set by a power or energy aware scheduling
strategy to a value between p1 and p2 that lets the job run within the site's power goal. The job
may be delayed if p1 is higher than a frequency that allows the job to run withing the goal.

If the current frequency is < min, it will be set to min. Likewise, if the current frequency is >
max, it will be set to max.

Acceptable values at present include:

#### frequency in kilohertz

Low the lowest available frequency

High the highest available frequency

HighM1 (high minus one) will select the next highest available frequency

Medium attempts to set a frequency in the middle of the available range

Conservative attempts to use the Conservative CPU governor

OnDemand attempts to use the OnDemand CPU governor (the default value)

Performance attempts to use the Performance CPU governor

PowerSave attempts to use the PowerSave CPU governor

UserSpace attempts to use the UserSpace CPU governor

The following informational environment variable is set in the job
step when --cpu-freq option is requested.
SLURM_CPU_FREQ_REQ

This environment variable can also be used to supply the value for the CPU frequency request if it
is set when the 'srun' command is issued. The --cpu-freq on the command line will override the
environment variable value. The form on the environment variable is the same as the command line.
See the ENVIRONMENT VARIABLES section for a description of the SLURM_CPU_FREQ_REQ variable.

NOTE: This parameter is treated as a request, not a requirement. If the job step's node does not
support setting the CPU frequency, or the requested value is outside the bounds of the legal
frequencies, an error is logged, but the job step is allowed to continue.

NOTE: Setting the frequency for just the CPUs of the job step implies that the tasks are confined
to those CPUs. If task confinement (i.e., TaskPlugin=task/affinity or TaskPlugin=task/cgroup with
the "ConstrainCores" option) is not configured, this parameter is ignored.

NOTE: When the step completes, the frequency and governor of each selected CPU is reset to the
configured CpuFreqDef value with a default value of the OnDemand CPU governor.

NOTE: When submitting jobs with the --cpu-freq option with linuxproc as the ProctrackType can
cause jobs to run too quickly before Accounting is able to poll for job information. As a result
not all of accounting information will be present.

-c, --cpus-per-task=<ncpus>
Advise the Slurm controller that ensuing job steps will require ncpus number of processors per
task. Without this option, the controller will just try to allocate one processor per task.

For instance, consider an application that has 4 tasks, each requiring 3 processors. If our
cluster is comprised of quad-processors nodes and we simply ask for 12 processors, the controller
might give us only 3 nodes. However, by using the --cpus-per-task=3 options, the controller knows
that each task requires 3 processors on the same node, and the controller will grant an allocation
of 4 nodes, one for each of the 4 tasks.

-d, --dependency=<dependency_list>
Defer the start of this job until the specified dependencies have been satisfied completed.
<dependency_list> is of the form <type:job_id[:job_id][,type:job_id[:job_id]]> or
<type:job_id[:job_id][?type:job_id[:job_id]]>. All dependencies must be satisfied if the ","
separator is used. Any dependency may be satisfied if the "?" separator is used. Many jobs can
share the same dependency and these jobs may even belong to different users. The value may be
changed after job submission using the scontrol command. Once a job dependency fails due to the
termination state of a preceding job, the dependent job will never be run, even if the preceding
job is requeued and has a different termination state in a subsequent execution.

after:job_id[:jobid...]
This job can begin execution after the specified jobs have begun execution.

afterany:job_id[:jobid...]
This job can begin execution after the specified jobs have terminated.

afternotok:job_id[:jobid...]
This job can begin execution after the specified jobs have terminated in some failed state
(non-zero exit code, node failure, timed out, etc).

afterok:job_id[:jobid...]
This job can begin execution after the specified jobs have successfully executed (ran to
completion with an exit code of zero).

expand:job_id
Resources allocated to this job should be used to expand the specified job. The job to
expand must share the same QOS (Quality of Service) and partition. Gang scheduling of
resources in the partition is also not supported.

singleton
This job can begin execution after any previously launched jobs sharing the same job name
and user have terminated.

-D, --chdir=<path>
Change directory to path before beginning execution. The path can be specified as full path or
relative path to the directory where the command is executed.

--exclusive[=user]
The job allocation can not share nodes with other running jobs (or just other users with the
"=user" option). The default shared/exclusive behavior depends on system configuration and the
partition's Shared option takes precedence over the job's option.

-F, --nodefile=<node file>
Much like --nodelist, but the list is contained in a file of name node file. The node names of
the list may also span multiple lines in the file. Duplicate node names in the file will be
ignored. The order of the node names in the list is not important; the node names will be sorted
by Slurm.

--get-user-env[=timeout][mode]
This option will load login environment variables for the user specified in the --uid option. The
environment variables are retrieved by running something of this sort "su - <username> -c
/usr/bin/env" and parsing the output. Be aware that any environment variables already set in
salloc's environment will take precedence over any environment variables in the user's login
environment. The optional timeout value is in seconds. Default value is 3 seconds. The optional
mode value control the "su" options. With a mode value of "S", "su" is executed without the "-"
option. With a mode value of "L", "su" is executed with the "-" option, replicating the login
environment. If mode not specified, the mode established at Slurm build time is used. Example of
use include "--get-user-env", "--get-user-env=10" "--get-user-env=10L", and "--get-user-env=S".
NOTE: This option only works if the caller has an effective uid of "root". This option was
originally created for use by Moab.

--gid=<group>
Submit the job with the specified group's group access permissions. group may be the group name
or the numerical group ID. In the default Slurm configuration, this option is only valid when
used by the user root.

--gres=<list>
Specifies a comma delimited list of generic consumable resources. The format of each entry on the
list is "name[[:type]:count]". The name is that of the consumable resource. The count is the
number of those resources with a default value of 1. The specified resources will be allocated to
the job on each node. The available generic consumable resources is configurable by the system
administrator. A list of available generic consumable resources will be printed and the command
will exit if the option argument is "help". Examples of use include "--gres=gpu:2,mic=1",
"--gres=gpu:kepler:2", and "--gres=help".

-H, --hold
Specify the job is to be submitted in a held state (priority of zero). A held job can now be
released using scontrol to reset its priority (e.g. "scontrol release <job_id>").

-h, --help
Display help information and exit.

--hint=<type>
Bind tasks according to application hints.

compute_bound
Select settings for compute bound applications: use all cores in each socket, one thread
per core.

memory_bound
Select settings for memory bound applications: use only one core in each socket, one thread
per core.

[no]multithread
[don't] use extra threads with in-core multi-threading which can benefit communication
intensive applications. Only supported with the task/affinity plugin.

help show this help message

-I, --immediate[=<seconds>]
exit if resources are not available within the time period specified. If no argument is given,
resources must be available immediately for the request to succeed. By default, --immediate is
off, and the command will block until resources become available. Since this option's argument is
optional, for proper parsing the single letter option must be followed immediately with the value
and not include a space between them. For example "-I60" and not "-I 60".

-J, --job-name=<jobname>
Specify a name for the job allocation. The specified name will appear along with the job id number
when querying running jobs on the system. The default job name is the name of the "command"
specified on the command line.

--jobid=<jobid>
Allocate resources as the specified job id. NOTE: Only valid for user root.

-K, --kill-command[=signal]
salloc always runs a user-specified command once the allocation is granted. salloc will wait
indefinitely for that command to exit. If you specify the --kill-command option salloc will send
a signal to your command any time that the Slurm controller tells salloc that its job allocation
has been revoked. The job allocation can be revoked for a couple of reasons: someone used scancel
to revoke the allocation, or the allocation reached its time limit. If you do not specify a
signal name or number and Slurm is configured to signal the spawned command at job termination,
the default signal is SIGHUP for interactive and SIGTERM for non-interactive sessions. Since this
option's argument is optional, for proper parsing the single letter option must be followed
immediately with the value and not include a space between them. For example "-K1" and not "-K 1".

-k, --no-kill
Do not automatically terminate a job if one of the nodes it has been allocated fails. The user
will assume the responsibilities for fault-tolerance should a node fail. When there is a node
failure, any active job steps (usually MPI jobs) on that node will almost certainly suffer a fatal
error, but with --no-kill, the job allocation will not be revoked so the user may launch new job
steps on the remaining nodes in their allocation.

By default Slurm terminates the entire job allocation if any node fails in its range of allocated
nodes.

-L, --licenses=<license>
Specification of licenses (or other resources available on all nodes of the cluster) which must be
allocated to this job. License names can be followed by a colon and count (the default count is
one). Multiple license names should be comma separated (e.g. "--licenses=foo:4,bar").

Specify alternate distribution methods for remote processes. In salloc, this only sets
environment variables that will be used by subsequent srun requests. This option controls the
assignment of tasks to the nodes on which resources have been allocated, and the distribution of
those resources to tasks for binding (task affinity). The first distribution method (before the
":") controls the distribution of resources across nodes. The optional second distribution method
(after the ":") controls the distribution of resources across sockets within a node. Note that
with select/cons_res, the number of cpus allocated on each socket and node may be different. Refer
to http://slurm.schedmd.com/mc_support.html for more information on resource allocation,
assignment of tasks to nodes, and binding of tasks to CPUs.

First distribution method:

block The block distribution method will distribute tasks to a node such that consecutive tasks
share a node. For example, consider an allocation of three nodes each with two cpus. A
four-task block distribution request will distribute those tasks to the nodes with tasks
one and two on the first node, task three on the second node, and task four on the third
node. Block distribution is the default behavior if the number of tasks exceeds the number
of allocated nodes.

cyclic The cyclic distribution method will distribute tasks to a node such that consecutive tasks
are distributed over consecutive nodes (in a round-robin fashion). For example, consider an
allocation of three nodes each with two cpus. A four-task cyclic distribution request will
distribute those tasks to the nodes with tasks one and four on the first node, task two on
the second node, and task three on the third node. Note that when SelectType is
select/cons_res, the same number of CPUs may not be allocated on each node. Task
distribution will be round-robin among all the nodes with CPUs yet to be assigned to tasks.
Cyclic distribution is the default behavior if the number of tasks is no larger than the
number of allocated nodes.

plane The tasks are distributed in blocks of a specified size. The options include a number
representing the size of the task block. This is followed by an optional specification of
the task distribution scheme within a block of tasks and between the blocks of tasks. The
number of tasks distributed to each node is the same as for cyclic distribution, but the
taskids assigned to each node depend on the plane size. For more details (including
examples and diagrams), please see
http://slurm.schedmd.com/mc_support.html
and
http://slurm.schedmd.com/dist_plane.html

arbitrary
The arbitrary method of distribution will allocate processes in-order as listed in file
designated by the environment variable SLURM_HOSTFILE. If this variable is listed it will
over ride any other method specified. If not set the method will default to block. Inside
the hostfile must contain at minimum the number of hosts requested and be one per line or
comma separated. If specifying a task count (-n, --ntasks=<number>), your tasks will be
laid out on the nodes in the order of the file.
NOTE: The arbitrary distribution option on a job allocation only controls the nodes to be
allocated to the job and not the allocation of CPUs on those nodes. This option is meant
primarily to control a job step's task layout in an existing job allocation for the srun
command.

Second distribution method:

block The block distribution method will distribute tasks to sockets such that consecutive tasks
share a socket.

cyclic The cyclic distribution method will distribute tasks to sockets such that consecutive tasks
are distributed over consecutive sockets (in a round-robin fashion). Tasks requiring more
than one CPU will have all of those CPUs allocated on a single socket if possible.

fcyclic
The fcyclic distribution method will distribute tasks to sockets such that consecutive
tasks are distributed over consecutive sockets (in a round-robin fashion). Tasks requiring
more than one CPU will have each CPUs allocated in a cyclic fashion across sockets.

--mail-type=<type>
Notify user by email when certain event types occur. Valid type values are NONE, BEGIN, END,
FAIL, REQUEUE, ALL (equivalent to BEGIN, END, FAIL, REQUEUE, and STAGE_OUT), STAGE_OUT (burst
buffer stage out completed), TIME_LIMIT, TIME_LIMIT_90 (reached 90 percent of time limit),
TIME_LIMIT_80 (reached 80 percent of time limit), and TIME_LIMIT_50 (reached 50 percent of time
limit). Multiple type values may be specified in a comma separated list. The user to be notified
is indicated with --mail-user.

--mail-user=<user>
User to receive email notification of state changes as defined by --mail-type. The default value
is the submitting user.

--mem=<MB>
Specify the real memory required per node in MegaBytes. Default value is DefMemPerNode and the
maximum value is MaxMemPerNode. If configured, both of parameters can be seen using the scontrol
show config command. This parameter would generally be used if whole nodes are allocated to jobs
(SelectType=select/linear). Also see --mem-per-cpu. --mem and --mem-per-cpu are mutually
exclusive. NOTE: A memory size specification is treated as a special case and grants the job
access to all of the memory on each node. NOTE: Enforcement of memory limits currently relies
upon the task/cgroup plugin or enabling of accounting, which samples memory use on a periodic
basis (data need not be stored, just collected). In both cases memory use is based upon the job's
Resident Set Size (RSS). A task may exceed the memory limit until the next periodic accounting
sample.

--mem-per-cpu=<MB>
Mimimum memory required per allocated CPU in MegaBytes. Default value is DefMemPerCPU and the
maximum value is MaxMemPerCPU (see exception below). If configured, both of parameters can be seen
using the scontrol show config command. Note that if the job's --mem-per-cpu value exceeds the
configured MaxMemPerCPU, then the user's limit will be treated as a memory limit per task;
--mem-per-cpu will be reduced to a value no larger than MaxMemPerCPU; --cpus-per-task will be set
and the value of --cpus-per-task multiplied by the new --mem-per-cpu value will equal the original
--mem-per-cpu value specified by the user. This parameter would generally be used if individual
processors are allocated to jobs (SelectType=select/cons_res). If resources are allocated by the
core, socket or whole nodes; the number of CPUs allocated to a job may be higher than the task
count and the value of --mem-per-cpu should be adjusted accordingly. Also see --mem. --mem and
--mem-per-cpu are mutually exclusive.

--mem_bind=[{quiet,verbose},]type
Bind tasks to memory. Used only when the task/affinity plugin is enabled and the NUMA memory
functions are available. Note that the resolution of CPU and memory binding may differ on some
architectures. For example, CPU binding may be performed at the level of the cores within a
processor while memory binding will be performed at the level of nodes, where the definition of
"nodes" may differ from system to system. The use of any type other than "none" or "local" is not
recommended. If you want greater control, try running a simple test code with the options
"--mem_bind=verbose,none" to determine the specific configuration.

NOTE: To have Slurm always report on the selected memory binding for all commands executed in a
shell, you can enable verbose mode by setting the SLURM_MEM_BIND environment variable value to
"verbose".

The following informational environment variables are set when --mem_bind is in use:

SLURM_MEM_BIND_VERBOSE
SLURM_MEM_BIND_TYPE
SLURM_MEM_BIND_LIST

See the ENVIRONMENT VARIABLES section for a more detailed description of the individual
SLURM_MEM_BIND* variables.

Supported options include:

q[uiet]
quietly bind before task runs (default)

v[erbose]
verbosely report binding before task runs

no[ne] don't bind tasks to memory (default)

rank bind by task rank (not recommended)

local Use memory local to the processor in use

map_mem:<list>
bind by mapping a node's memory to tasks as specified where <list> is
<cpuid1>,<cpuid2>,...<cpuidN>. CPU IDs are interpreted as decimal values unless they are
preceded with '0x' in which case they interpreted as hexadecimal values (not recommended)

mask_mem:<list>
bind by setting memory masks on tasks as specified where <list> is
<mask1>,<mask2>,...<maskN>. memory masks are always interpreted as hexadecimal values.
Note that masks must be preceded with a '0x' if they don't begin with [0-9] so they are
seen as numerical values by srun.

help show this help message

--mincpus=<n>
Specify a minimum number of logical cpus/processors per node.

-N, --nodes=<minnodes[-maxnodes]>
Request that a minimum of minnodes nodes be allocated to this job. A maximum node count may also
be specified with maxnodes. If only one number is specified, this is used as both the minimum and
maximum node count. The partition's node limits supersede those of the job. If a job's node
limits are outside of the range permitted for its associated partition, the job will be left in a
PENDING state. This permits possible execution at a later time, when the partition limit is
changed. If a job node limit exceeds the number of nodes configured in the partition, the job
will be rejected. Note that the environment variable SLURM_NNODES will be set to the count of
nodes actually allocated to the job. See the ENVIRONMENT VARIABLES section for more information.
If -N is not specified, the default behavior is to allocate enough nodes to satisfy the
requirements of the -n and -c options. The job will be allocated as many nodes as possible within
the range specified and without delaying the initiation of the job. The node count specification
may include a numeric value followed by a suffix of "k" (multiplies numeric value by 1,024) or "m"
(multiplies numeric value by 1,048,576).

-n, --ntasks=<number>
salloc does not launch tasks, it requests an allocation of resources and executed some command.
This option advises the Slurm controller that job steps run within this allocation will launch a
maximum of number tasks and sufficient resources are allocated to accomplish this. The default is
one task per node, but note that the --cpus-per-task option will change this default.

--network=<type>
Specify information pertaining to the switch or network. The interpretation of type is system
dependent. This option is supported when running Slurm on a Cray natively. It is used to request
using Network Performace Counters. Only one value per request is valid. All options are case
in-sensitive. In this configuration supported values include:

system
Use the system-wide network performance counters. Only nodes requested will be marked in use
for the job allocation. If the job does not fill up the entire system the rest of the nodes
are not able to be used by other jobs using NPC, if idle their state will appear as
PerfCnts. These nodes are still available for other jobs not using NPC.

blade Use the blade network performance counters. Only nodes requested will be marked in use for
the job allocation. If the job does not fill up the entire blade(s) allocated to the job
those blade(s) are not able to be used by other jobs using NPC, if idle their state will
appear as PerfCnts. These nodes are still available for other jobs not using NPC.

In all cases the job allocation request must specify the
--exclusive option. Otherwise the request will be denied.

Also with any of these options steps are not allowed to share blades, so resources would remain
idle inside an allocation if the step running on a blade does not take up all the nodes on the
blade.

The network option is also supported on systems with IBM's Parallel Environment (PE). See IBM's
LoadLeveler job command keyword documentation about the keyword "network" for more information.
Multiple values may be specified in a comma separated list. All options are case in-sensitive.
Supported values include:

BULK_XFER[=<resources>]
Enable bulk transfer of data using Remote Direct-Memory Access (RDMA). The optional
resources specification is a numeric value which can have a suffix of "k", "K", "m",
"M", "g" or "G" for kilobytes, megabytes or gigabytes. NOTE: The resources
specification is not supported by the underlying IBM infrastructure as of Parallel
Environment version 2.2 and no value should be specified at this time.

CAU=<count> Number of Collectve Acceleration Units (CAU) required. Applies only to IBM Power7-IH
processors. Default value is zero. Independent CAU will be allocated for each
programming interface (MPI, LAPI, etc.)

DEVNAME=<name>
Specify the device name to use for communications (e.g. "eth0" or "mlx4_0").

DEVTYPE=<type>
Specify the device type to use for communications. The supported values of type are:
"IB" (InfiniBand), "HFI" (P7 Host Fabric Interface), "IPONLY" (IP-Only interfaces),
"HPCE" (HPC Ethernet), and "KMUX" (Kernel Emulation of HPCE). The devices allocated
to a job must all be of the same type. The default value depends upon depends upon
what hardware is available and in order of preferences is IPONLY (which is not
considered in User Space mode), HFI, IB, HPCE, and KMUX.

IMMED =<count>
Number of immediate send slots per window required. Applies only to IBM Power7-IH
processors. Default value is zero.

INSTANCES =<count>
Specify number of network connections for each task on each network connection. The
default instance count is 1.

IPV4 Use Internet Protocol (IP) version 4 communications (default).

IPV6 Use Internet Protocol (IP) version 6 communications.

LAPI Use the LAPI programming interface.

MPI Use the MPI programming interface. MPI is the default interface.

PAMI Use the PAMI programming interface.

SHMEM Use the OpenSHMEM programming interface.

SN_ALL Use all available switch networks (default).

SN_SINGLE Use one available switch network.

UPC Use the UPC programming interface.

US Use User Space communications.

Some examples of network specifications:

Instances=2,US,MPI,SN_ALL
Create two user space connections for MPI communications on every switch network for
each task.

US,MPI,Instances=3,Devtype=IB
Create three user space connections for MPI communications on every InfiniBand network
for each task.

IPV4,LAPI,SN_Single
Create a IP version 4 connection for LAPI communications on one switch network for
each task.

Instances=2,US,LAPI,MPI
Create two user space connections each for LAPI and MPI communications on every switch
network for each task. Note that SN_ALL is the default option so every switch network
is used. Also note that Instances=2 specifies that two connections are established for
each protocol (LAPI and MPI) and each task. If there are two networks and four tasks
on the node then a total of 32 connections are established (2 instances x 2 protocols
x 2 networks x 4 tasks).

--nice[=adjustment]
Run the job with an adjusted scheduling priority within Slurm. With no adjustment value the
scheduling priority is decreased by 100. The adjustment range is from -10000 (highest priority) to
10000 (lowest priority). Only privileged users can specify a negative adjustment. NOTE: This
option is presently ignored if SchedulerType=sched/wiki or SchedulerType=sched/wiki2.

--ntasks-per-core=<ntasks>
Request the maximum ntasks be invoked on each core. Meant to be used with the --ntasks option.
Related to --ntasks-per-node except at the core level instead of the node level. NOTE: This
option is not supported unless SelectTypeParameters=CR_Core or SelectTypeParameters=CR_Core_Memory
is configured.

--ntasks-per-socket=<ntasks>
Request the maximum ntasks be invoked on each socket. Meant to be used with the --ntasks option.
Related to --ntasks-per-node except at the socket level instead of the node level. NOTE: This
option is not supported unless SelectTypeParameters=CR_Socket or
SelectTypeParameters=CR_Socket_Memory is configured.

--ntasks-per-node=<ntasks>
Request that ntasks be invoked on each node. If used with the --ntasks option, the --ntasks
option will take precedence and the --ntasks-per-node will be treated as a maximum count of tasks
per node. Meant to be used with the --nodes option. This is related to --cpus-per-task=ncpus,
but does not require knowledge of the actual number of cpus on each node. In some cases, it is
more convenient to be able to request that no more than a specific number of tasks be invoked on
each node. Examples of this include submitting a hybrid MPI/OpenMP app where only one MPI
"task/rank" should be assigned to each node while allowing the OpenMP portion to utilize all of
the parallelism present in the node, or submitting a single setup/cleanup/monitoring job to each
node of a pre-existing allocation as one step in a larger job script.

--no-bell
Silence salloc's use of the terminal bell. Also see the option --bell.

--no-shell
immediately exit after allocating resources, without running a command. However, the Slurm job
will still be created and will remain active and will own the allocated resources as long as it is
active. You will have a Slurm job id with no associated processes or tasks. You can submit srun
commands against this resource allocation, if you specify the --jobid= option with the job id of
this Slurm job. Or, this can be used to temporarily reserve a set of resources so that other jobs
cannot use them for some period of time. (Note that the Slurm job is subject to the normal
constraints on jobs, including time limits, so that eventually the job will terminate and the
resources will be freed, or you can terminate the job manually using the scancel command.)

-O, --overcommit
Overcommit resources. When applied to job allocation, only one CPU is allocated to the job per
node and options used to specify the number of tasks per node, socket, core, etc. are ignored.
When applied to job step allocations (the srun command when executed within an existing job
allocation), this option can be used to launch more than one task per CPU. Normally, srun will
not allocate more than one process per CPU. By specifying --overcommit you are explicitly
allowing more than one process per CPU. However no more than MAX_TASKS_PER_NODE tasks are
permitted to execute per node. NOTE: MAX_TASKS_PER_NODE is defined in the file slurm.h and is not
a variable, it is set at Slurm build time.

--power=<flags>
Comma separated list of power management plugin options. Currently available flags include: level
(all nodes allocated to the job should have identical power caps, may be disabled by the Slurm
configuration option PowerParameters=job_no_level).

--priority=<value>
Request a specific job priority. May be subject to configuration specific constraints. Only
Slurm operators and administrators can set the priority of a job.

All All data types are collected. (Cannot be combined with other values.)

None No data types are collected. This is the default.
(Cannot be combined with other values.)

Energy Energy data is collected.

Task Task (I/O, Memory, ...) data is collected.

Lustre Lustre data is collected.

Network Network (InfiniBand) data is collected.

-p, --partition=<partition_names>
Request a specific partition for the resource allocation. If not specified, the default behavior
is to allow the slurm controller to select the default partition as designated by the system
administrator. If the job can use more than one partition, specify their names in a comma separate
list and the one offering earliest initiation will be used with no regard given to the partition
name ordering (although higher priority partitions will be considered first). When the job is
initiated, the name of the partition used will be placed first in the job record partition string.

-Q, --quiet
Suppress informational messages from salloc. Errors will still be displayed.

--qos=<qos>
Request a quality of service for the job. QOS values can be defined for each user/cluster/account
association in the Slurm database. Users will be limited to their association's defined set of
qos's when the Slurm configuration parameter, AccountingStorageEnforce, includes "qos" in it's
definition.

--reboot
Force the allocated nodes to reboot before starting the job. This is only supported with some
system configurations and will otherwise be silently ignored.

--reservation=<name>
Allocate resources for the job from the named reservation.

-s, --share
The job allocation can share resources with other running jobs. The resources to be shared can be
nodes, sockets, cores, or hyperthreads depending upon configuration. The default shared behavior
depends on system configuration and the partition's Shared option takes precedence over the job's
option. This option may result in the allocation being granted sooner than if the --share option
was not set and allow higher system utilization, but application performance will likely suffer
due to competition for resources. Also see the --exclusive option.

-S, --core-spec=<num>
Count of specialized cores per node reserved by the job for system operations and not used by the
application. The application will not use these cores, but will be charged for their allocation.
Default value is dependent upon the node's configured CoreSpecCount value. If a value of zero is
designated and the Slurm configuration option AllowSpecResourcesUsage is enabled, the job will be
allowed to override CoreSpecCount and use the specialized resources on nodes it is allocated.
This option can not be used with the --thread-spec option.

--sicp Identify a job as one which jobs submitted to other clusters can be dependent upon.

--signal=<sig_num>[@<sig_time>]
When a job is within sig_time seconds of its end time, send it the signal sig_num. Due to the
resolution of event handling by Slurm, the signal may be sent up to 60 seconds earlier than
specified. sig_num may either be a signal number or name (e.g. "10" or "USR1"). sig_time must
have an integer value between 0 and 65535. By default, no signal is sent before the job's end
time. If a sig_num is specified without any sig_time, the default time will be 60 seconds.

--sockets-per-node=<sockets>
Restrict node selection to nodes with at least the specified number of sockets. See additional
information under -B option above when task/affinity plugin is enabled.

--switches=<count>[@<max-time>]
When a tree topology is used, this defines the maximum count of switches desired for the job
allocation and optionally the maximum time to wait for that number of switches. If Slurm finds an
allocation containing more switches than the count specified, the job remains pending until it
either finds an allocation with desired switch count or the time limit expires. It there is no
switch count limit, there is no delay in starting the job. Acceptable time formats include
"minutes", "minutes:seconds", "hours:minutes:seconds", "days-hours", "days-hours:minutes" and
"days-hours:minutes:seconds". The job's maximum time delay may be limited by the system
administrator using the SchedulerParameters configuration parameter with the max_switch_wait
parameter option. The default max-time is the max_switch_wait SchedulerParameters.

-t, --time=<time>
Set a limit on the total run time of the job allocation. If the requested time limit exceeds the
partition's time limit, the job will be left in a PENDING state (possibly indefinitely). The
default time limit is the partition's default time limit. When the time limit is reached, each
task in each job step is sent SIGTERM followed by SIGKILL. The interval between signals is
specified by the Slurm configuration parameter KillWait. The OverTimeLimit configuration
parameter may permit the job to run longer than scheduled. Time resolution is one minute and
second values are rounded up to the next minute.

A time limit of zero requests that no time limit be imposed. Acceptable time formats include
"minutes", "minutes:seconds", "hours:minutes:seconds", "days-hours", "days-hours:minutes" and
"days-hours:minutes:seconds".

--thread-spec=<num>
Count of specialized threads per node reserved by the job for system operations and not used by
the application. The application will not use these threads, but will be charged for their
allocation. This option can not be used with the --core-spec option.

--threads-per-core=<threads>
Restrict node selection to nodes with at least the specified number of threads per core. NOTE:
"Threads" refers to the number of processing units on each core rather than the number of
application tasks to be launched per core. See additional information under -B option above when
task/affinity plugin is enabled.

--time-min=<time>
Set a minimum time limit on the job allocation. If specified, the job may have it's --time limit
lowered to a value no lower than --time-min if doing so permits the job to begin execution earlier
than otherwise possible. The job's time limit will not be changed after the job is allocated
resources. This is performed by a backfill scheduling algorithm to allocate resources otherwise
reserved for higher priority jobs. Acceptable time formats include "minutes", "minutes:seconds",
"hours:minutes:seconds", "days-hours", "days-hours:minutes" and "days-hours:minutes:seconds".

--tmp=<MB>
Specify a minimum amount of temporary disk space.

-u, --usage
Display brief help message and exit.

--uid=<user>
Attempt to submit and/or run a job as user instead of the invoking user id. The invoking user's
credentials will be used to check access permissions for the target partition. This option is only
valid for user root. This option may be used by user root may use this option to run jobs as a
normal user in a RootOnly partition for example. If run as root, salloc will drop its permissions
to the uid specified after node allocation is successful. user may be the user name or numerical
user ID.

-V, --version
Display version information and exit.

-v, --verbose
Increase the verbosity of salloc's informational messages. Multiple -v's will further increase
salloc's verbosity. By default only errors will be displayed.

-w, --nodelist=<node name list>
Request a specific list of hosts. The job will contain all of these hosts and possibly additional
hosts as needed to satisfy resource requirements. The list may be specified as a comma-separated
list of hosts, a range of hosts (host[1-5,7,...] for example), or a filename. The host list will
be assumed to be a filename if it contains a "/" character. If you specify a minimum node or
processor count larger than can be satisfied by the supplied host list, additional resources will
be allocated on other nodes as needed. Duplicate node names in the list will be ignored. The
order of the node names in the list is not important; the node names will be sorted by Slurm.

--wait-all-nodes=<value>
Controls when the execution of the command begins. By default the job will begin execution as
soon as the allocation is made.

0 Begin execution as soon as allocation can be made. Do not wait for all nodes to be ready for
use (i.e. booted).

1 Do not begin execution until all nodes are ready for use.

--wckey=<wckey>
Specify wckey to be used with job. If TrackWCKey=no (default) in the slurm.conf this value is
ignored.

-x, --exclude=<node name list>
Explicitly exclude certain nodes from the resources granted to the job.

The following options support Blue Gene systems, but may be applicable to other systems as well.

--blrts-image=<path>
Path to blrts image for bluegene block. BGL only. Default from blugene.conf if not set.

--cnload-image=<path>
Path to compute node image for bluegene block. BGP only. Default from blugene.conf if not set.

--conn-type=<type>
Require the block connection type to be of a certain type. On Blue Gene the acceptable of type
are MESH, TORUS and NAV. If NAV, or if not set, then Slurm will try to fit a what the
DefaultConnType is set to in the bluegene.conf if that isn't set the default is TORUS. You should
not normally set this option. If running on a BGP system and wanting to run in HTC mode (only for
1 midplane and below). You can use HTC_S for SMP, HTC_D for Dual, HTC_V for virtual node mode,
and HTC_L for Linux mode. For systems that allow a different connection type per dimension you
can supply a comma separated list of connection types may be specified, one for each dimension
(i.e. M,T,T,T will give you a torus connection is all dimensions expect the first).

-g, --geometry=<XxYxZ> | <AxXxYxZ>
Specify the geometry requirements for the job. On BlueGene/L and BlueGene/P systems there are
three numbers giving dimensions in the X, Y and Z directions, while on BlueGene/Q systems there
are four numbers giving dimensions in the A, X, Y and Z directions and can not be used to allocate
sub-blocks. For example "--geometry=1x2x3x4", specifies a block of nodes having 1 x 2 x 3 x 4 =
24 nodes (actually midplanes on BlueGene).

--ioload-image=<path>
Path to io image for bluegene block. BGP only. Default from blugene.conf if not set.

--linux-image=<path>
Path to linux image for bluegene block. BGL only. Default from blugene.conf if not set.

--mloader-image=<path>
Path to mloader image for bluegene block. Default from blugene.conf if not set.

-R, --no-rotate
Disables rotation of the job's requested geometry in order to fit an appropriate block. By
default the specified geometry can rotate in three dimensions.

--ramdisk-image=<path>
Path to ramdisk image for bluegene block. BGL only. Default from blugene.conf if not set.

INPUT ENVIRONMENT VARIABLES

       Upon startup, salloc will read and handle the options set in the following environment variables.   Note:
       Command line options always override environment variables settings.

       SALLOC_ACCOUNT        Same as -A, --account

       SALLOC_ACCTG_FREQ     Same as --acctg-freq

       SALLOC_BELL           Same as --bell

       SALLOC_BURST_BUFFER   Same as --bb

       SALLOC_CONN_TYPE      Same as --conn-type

       SALLOC_CORE_SPEC      Same as --core-spec

       SALLOC_DEBUG          Same as -v, --verbose

       SALLOC_EXCLUSIVE      Same as --exclusive

       SALLOC_GEOMETRY       Same as -g, --geometry

       SALLOC_HINT or SLURM_HINT
                             Same as --hint

       SALLOC_IMMEDIATE      Same as -I, --immediate

       SALLOC_JOBID          Same as --jobid

       SALLOC_KILL_CMD       Same as -K, --kill-command

       SALLOC_MEM_BIND       Same as --mem_bind

       SALLOC_NETWORK        Same as --network

       SALLOC_NO_BELL        Same as --no-bell

       SALLOC_NO_ROTATE      Same as -R, --no-rotate

       SALLOC_OVERCOMMIT     Same as -O, --overcommit

       SALLOC_PARTITION      Same as -p, --partition

       SALLOC_POWER          Same as --power

       SALLOC_PROFILE        Same as --profile

       SALLOC_QOS            Same as --qos

       SALLOC_REQ_SWITCH     When  a  tree  topology is used, this defines the maximum count of switches desired
                             for the job allocation and optionally the maximum time to wait for that  number  of
                             switches. See --switches.

       SALLOC_RESERVATION    Same as --reservation

       SALLOC_SICP           Same as --sicp

       SALLOC_SIGNAL         Same as --signal

       SALLOC_THREAD_SPEC    Same as --thread-spec

       SALLOC_TIMELIMIT      Same as -t, --time

       SALLOC_WAIT_ALL_NODES Same as --wait-all-nodes

       SALLOC_WCKEY          Same as --wckey

       SALLOC_WAIT4SWITCH    Max time waiting for requested switches. See --switches

       SLURM_CONF            The location of the Slurm configuration file.

       SLURM_EXIT_ERROR      Specifies the exit code generated when a Slurm error occurs (e.g. invalid options).
                             This can be used by a script to distinguish application  exit  codes  from  various
                             Slurm error conditions.  Also see SLURM_EXIT_IMMEDIATE.

       SLURM_EXIT_IMMEDIATE  Specifies the exit code generated when the --immediate option is used and resources
                             are not currently  available.   This  can  be  used  by  a  script  to  distinguish
                             application   exit   codes   from   various   Slurm  error  conditions.   Also  see
                             SLURM_EXIT_ERROR.

OUTPUT ENVIRONMENT VARIABLES

salloc will set the following environment variables in the environment of the executed program:

BASIL_RESERVATION_ID
The reservation ID on Cray systems running ALPS/BASIL only.

SLURM_CLUSTER_NAME
Name of the cluster on which the job is executing.

MPIRUN_NOALLOCATE
Do not allocate a block on Blue Gene L/P systems only.

MPIRUN_NOFREE
Do not free a block on Blue Gene L/P systems only.

MPIRUN_PARTITION
The block name on Blue Gene systems only.

SLURM_CPUS_PER_TASK
Number of cpus requested per task. Only set if the --cpus-per-task option is specified.

SLURM_DISTRIBUTION
Same as -m, --distribution

SLURM_JOB_ID (and SLURM_JOBID for backwards compatibility)
The ID of the job allocation.

SLURM_JOB_CPUS_PER_NODE
Count of processors available to the job on this node. Note the select/linear plugin allocates
entire nodes to jobs, so the value indicates the total count of CPUs on each node. The
select/cons_res plugin allocates individual processors to jobs, so this number indicates the
number of processors on each node allocated to the job allocation.

SLURM_JOB_NODELIST (and SLURM_NODELIST for backwards compatibility)
List of nodes allocated to the job.

SLURM_JOB_NUM_NODES (and SLURM_NNODES for backwards compatibility)
Total number of nodes in the job allocation.

SLURM_JOB_PARTITION
Name of the partition in which the job is running.

SLURM_MEM_BIND
Set to value of the --mem_bind option.

SLURM_SUBMIT_DIR
The directory from which salloc was invoked.

SLURM_SUBMIT_HOST
The hostname of the computer from which salloc was invoked.

SLURM_NODE_ALIASES
Sets of node name, communication address and hostname for nodes allocated to the job from the
cloud. Each element in the set if colon separated and each set is comma separated. For example:
SLURM_NODE_ALIASES=ec0:1.2.3.4:foo,ec1:1.2.3.5:bar

SLURM_NTASKS
Same as -n, --ntasks

SLURM_NTASKS_PER_NODE
Set to value of the --ntasks-per-node option, if specified.

SLURM_PROFILE
Same as --profile

SLURM_TASKS_PER_NODE
Number of tasks to be initiated on each node. Values are comma separated and in the same order as
SLURM_NODELIST. If two or more consecutive nodes are to have the same task count, that count is
followed by "(x#)" where "#" is the repetition count. For example, "SLURM_TASKS_PER_NODE=2(x3),1"
indicates that the first three nodes will each execute three tasks and the fourth node will
execute one task.

SIGNALS

       While  salloc  is  waiting  for  a  PENDING  job allocation, most signals will cause salloc to revoke the
       allocation request and exit.

       However if the allocation has been granted and salloc has already started  the  specified  command,  then
       salloc will ignore most signals.  salloc will not exit or release the allocation until the command exits.
       One notable exception is SIGHUP. A SIGHUP signal will cause salloc to release  the  allocation  and  exit
       without  waiting for the command to finish.  Another exception is SIGTERM, which will be forwarded to the
       spawned process.

EXAMPLES

       To get an allocation, and open a new xterm in which srun commands may be typed interactively:

              $ salloc -N16 xterm
              salloc: Granted job allocation 65537
              (at this point the xterm appears, and salloc waits for xterm to exit)
              salloc: Relinquishing job allocation 65537

       To grab an allocation of nodes and launch a parallel application on one command line (See the salloc  man
       page for more examples):

              salloc -N5 srun -n10 myprogram

COPYING

       Copyright  (C)  2006-2007  The  Regents  of the University of California.  Produced at Lawrence Livermore
       National Laboratory (cf, DISCLAIMER).
       Copyright (C) 2008-2010 Lawrence Livermore National Security.
       Copyright (C) 2010-2015 SchedMD LLC.

       This file is part of Slurm, a resource management program.  For details, see <http://slurm.schedmd.com/>.

       Slurm is free software; you can redistribute it and/or modify it under  the  terms  of  the  GNU  General
       Public License as published by the Free Software Foundation; either version 2 of the License, or (at your
       option) any later version.

       Slurm is distributed in the hope that it will be useful, but  WITHOUT  ANY  WARRANTY;  without  even  the
       implied  warranty  of  MERCHANTABILITY  or  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
       License for more details.