Provided by: slurm-client_21.08.5-2ubuntu1_amd64 
NAME
srun - Run parallel jobs
SYNOPSIS
srun [OPTIONS(0)... [executable(0) [args(0)...]]] [ : [OPTIONS(N)...]] executable(N) [args(N)...]
Option(s) define multiple jobs in a co-scheduled heterogeneous job. For more details about heterogeneous
jobs see the document
https://slurm.schedmd.com/heterogeneous_jobs.html
DESCRIPTION
Run a parallel job on cluster managed by Slurm. If necessary, srun will first create a resource
allocation in which to run the parallel job.
The following document describes the influence of various options on the allocation of cpus to jobs and
tasks.
https://slurm.schedmd.com/cpu_management.html
RETURN VALUE
srun will return the highest exit code of all tasks run or the highest signal (with the high-order bit
set in an 8-bit integer -- e.g. 128 + signal) of any task that exited with a signal.
The value 253 is reserved for out-of-memory errors.
EXECUTABLE PATH RESOLUTION
The executable is resolved in the following order:
1. If executable starts with ".", then path is constructed as: current working directory / executable
2. If executable starts with a "/", then path is considered absolute.
3. If executable can be resolved through PATH. See path_resolution(7).
4. If executable is in current working directory.
Current working directory is the calling process working directory unless the --chdir argument is passed,
which will override the current working directory.
OPTIONS
--accel-bind=<options>
Control how tasks are bound to generic resources of type gpu and nic. Multiple options may be
specified. Supported options include:
g Bind each task to GPUs which are closest to the allocated CPUs.
n Bind each task to NICs which are closest to the allocated CPUs.
v Verbose mode. Log how tasks are bound to GPU and NIC devices.
This option applies to job allocations.
-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. This option applies
to job allocations.
--acctg-freq=<datatype>=<interval>[,<datatype>=<interval>...]
Define the job accounting and profiling sampling intervals in seconds. This can be used to
override the JobAcctGatherFrequency parameter in the slurm.conf file. <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>
pairs may be specified. Supported datatype values are:
task Sampling interval 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.
It can not be disabled.
energy Sampling interval for energy profiling using the acct_gather_energy plugin.
network Sampling interval for infiniband profiling using the acct_gather_interconnect plugin.
filesystem Sampling interval for filesystem profiling using the acct_gather_filesystem plugin.
The default value for the task sampling interval is 30 seconds. 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. This option applies to
job allocations.
--bb=<spec>
Burst buffer specification. The form of the specification is system dependent. Also see --bbf.
This option applies to job allocations. When the --bb option is used, Slurm parses this option
and creates a temporary burst buffer script file that is used internally by the burst buffer
plugins. See Slurm's burst buffer guide for more information and examples:
https://slurm.schedmd.com/burst_buffer.html
--bbf=<file_name>
Path of file containing burst buffer specification. The form of the specification is system
dependent. Also see --bb. This option applies to job allocations. See Slurm's burst buffer guide
for more information and examples:
https://slurm.schedmd.com/burst_buffer.html
--bcast[=<dest_path>]
Copy executable file to allocated compute nodes. If a file name is specified, copy the executable
to the specified destination file path. If the path specified ends with '/' it is treated as a
target directory, and the destination file name will be slurm_bcast_<job_id>.<step_id>_<nodename>.
If no dest_path is specified and the slurm.conf BcastParameters DestDir is configured then it is
used, and the filename follows the above pattern. If none of the previous is specified, then
--chdir is used, and the filename follows the above pattern too. For example, "srun
--bcast=/tmp/mine -N3 a.out" will copy the file "a.out" from your current directory to the file
"/tmp/mine" on each of the three allocated compute nodes and execute that file. This option
applies to step allocations.
--bcast-exclude={NONE|<exclude_path>[,<exclude_path>...]}
Comma-separated list of absolute directory paths to be excluded when autodetecting and
broadcasting executable shared object dependencies through --bcast. If the keyword "NONE" is
configured, no directory paths will be excluded. The default value is that of slurm.conf
BcastExclude and this option overrides it. See also --bcast and --send-libs.
-b, --begin=<time>
Defer initiation of this job until the specified time. It accepts times 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.
This option applies to job allocations.
-D, --chdir=<path>
Have the remote processes do a chdir to path before beginning execution. The default is to chdir
to the current working directory of the srun process. The path can be specified as full path or
relative path to the directory where the command is executed. This option applies to job
allocations.
--cluster-constraint=<list>
Specifies features that a federated cluster must have to have a sibling job submitted to it. Slurm
will attempt to submit a sibling job to a cluster if it has at least one of the specified
features.
-M, --clusters=<string>
Clusters to issue commands to. Multiple cluster names may be comma separated. The job will be
submitted to the one cluster providing the earliest expected job initiation time. The default
value is the current cluster. A value of 'all' will query to run on all clusters. Note the
--export option to control environment variables exported between clusters. This option applies
only to job allocations. Note that the SlurmDBD must be up for this option to work properly.
--comment=<string>
An arbitrary comment. This option applies to job allocations.
--compress[=type]
Compress file before sending it to compute hosts. The optional argument specifies the data
compression library to be used. The default is BcastParameters Compression= if set or "lz4"
otherwise. Supported values are "lz4". Some compression libraries may be unavailable on some
systems. For use with the --bcast option. This option applies to step allocations.
-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. (some operators are not supported on
all system types). 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".
NOTE: This construct does not support multiple Intel KNL NUMA or MCDRAM modes. For example,
while --constraint="[(knl&quad)*2&(knl&hemi)*4]" is not supported,
--constraint="[haswell*2&(knl&hemi)*4]" is supported. Specification of multiple KNL modes
requires the use of a heterogeneous job.
Brackets
Brackets can be used to indicate that you are looking for a set of nodes with the different
requirements contained within the brackets. For example,
--constraint="[(rack1|rack2)*1&(rack3)*2]" will get you one node with either the "rack1" or
"rack2" features and two nodes with the "rack3" feature. The same request without the
brackets will try to find a single node that meets those requirements.
NOTE: Brackets are only reserved for Multiple Counts and Matching OR syntax. AND operators
require a count for each feature inside square brackets (i.e. "[quad*2&hemi*1]").
Parenthesis
Parenthesis can be used to group like node features together. For example,
--constraint="[(knl&snc4&flat)*4&haswell*1]" might be used to specify that four nodes with
the features "knl", "snc4" and "flat" plus one node with the feature "haswell" are
required. All options within parenthesis should be grouped with AND (e.g. "&") operands.
WARNING: When srun is executed from within salloc or sbatch, the constraint value can only contain
a single feature name. None of the other operators are currently supported for job steps.
This option applies to job and step allocations.
--container=<path_to_container>
Absolute path to OCI container bundle.
--contiguous
If set, then the allocated nodes must form a contiguous set.
NOTE: If SelectPlugin=cons_res this option won't be honored with the topology/tree or
topology/3d_torus plugins, both of which can modify the node ordering. This option applies to job
allocations.
-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. This option applies to job allocations.
NOTE: This option may implicitly impact the number of tasks if -n was not specified.
--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. This option
applies to job allocations.
--cpu-bind=[{quiet|verbose},]<type>
Bind tasks to CPUs. Used only when the task/affinity or task/cgroup plugin is enabled. NOTE: To
have Slurm always report on the selected CPU binding for all commands executed in a shell, you can
enable verbose mode by setting the SLURM_CPU_BIND environment variable value to "verbose".
The following informational environment variables are set when --cpu-bind is in use:
SLURM_CPU_BIND_VERBOSE
SLURM_CPU_BIND_TYPE
SLURM_CPU_BIND_LIST
See the ENVIRONMENT VARIABLES section for a more detailed description of the individual
SLURM_CPU_BIND variables. These variable are available only if the task/affinity plugin is
configured.
When using --cpus-per-task to run multithreaded tasks, be aware that CPU binding is inherited from
the parent of the process. This means that the multithreaded task should either specify or clear
the CPU binding itself to avoid having all threads of the multithreaded task use the same mask/CPU
as the parent. Alternatively, fat masks (masks which specify more than one allowed CPU) could be
used for the tasks in order to provide multiple CPUs for the multithreaded tasks.
Note that a job step can be allocated different numbers of CPUs on each node or be allocated CPUs
not starting at location zero. Therefore one of the options which automatically generate the task
binding is recommended. Explicitly specified masks or bindings are only honored when the job step
has been allocated every available CPU on the node.
Binding a task to a NUMA locality domain means to bind the task to the set of CPUs that belong to
the NUMA locality domain or "NUMA node". If NUMA locality domain options are used on systems with
no NUMA support, then each socket is considered a locality domain.
If the --cpu-bind option is not used, the default binding mode will depend upon Slurm's
configuration and the step's resource allocation. If all allocated nodes have the same configured
CpuBind mode, that will be used. Otherwise if the job's Partition has a configured CpuBind mode,
that will be used. Otherwise if Slurm has a configured TaskPluginParam value, that mode will be
used. Otherwise automatic binding will be performed as described below.
Auto Binding
Applies only when task/affinity is enabled. If the job step allocation includes an
allocation with a number of sockets, cores, or threads equal to the number of tasks times
cpus-per-task, then the tasks will by default be bound to the appropriate resources (auto
binding). Disable this mode of operation by explicitly setting "--cpu-bind=none". Use
TaskPluginParam=autobind=[threads|cores|sockets] to set a default cpu binding in case "auto
binding" doesn't find a match.
Supported options include:
q[uiet]
Quietly bind before task runs (default)
v[erbose]
Verbosely report binding before task runs
no[ne] Do not bind tasks to CPUs (default unless auto binding is applied)
rank Automatically bind by task rank. The lowest numbered task on each node is bound to
socket (or core or thread) zero, etc. Not supported unless the entire node is
allocated to the job.
map_cpu:<list>
Bind by setting CPU masks on tasks (or ranks) as specified where <list> is
<cpu_id_for_task_0>,<cpu_id_for_task_1>,... CPU IDs are interpreted as decimal
values unless they are preceded with '0x' in which case they interpreted as
hexadecimal values. If the number of tasks (or ranks) exceeds the number of
elements in this list, elements in the list will be reused as needed starting from
the beginning of the list. To simplify support for large task counts, the lists may
follow a map with an asterisk and repetition count. For example
"map_cpu:0x0f*4,0xf0*4".
mask_cpu:<list>
Bind by setting CPU masks on tasks (or ranks) as specified where <list> is
<cpu_mask_for_task_0>,<cpu_mask_for_task_1>,... The mapping is specified for a node
and identical mapping is applied to the tasks on every node (i.e. the lowest task ID
on each node is mapped to the first mask specified in the list, etc.). CPU masks
are always interpreted as hexadecimal values but can be preceded with an optional
'0x'. If the number of tasks (or ranks) exceeds the number of elements in this
list, elements in the list will be reused as needed starting from the beginning of
the list. To simplify support for large task counts, the lists may follow a map
with an asterisk and repetition count. For example "mask_cpu:0x0f*4,0xf0*4".
rank_ldom
Bind to a NUMA locality domain by rank. Not supported unless the entire node is
allocated to the job.
map_ldom:<list>
Bind by mapping NUMA locality domain IDs to tasks as specified where <list> is
<ldom1>,<ldom2>,...<ldomN>. The locality domain IDs are interpreted as decimal
values unless they are preceded with '0x' in which case they are interpreted as
hexadecimal values. Not supported unless the entire node is allocated to the job.
mask_ldom:<list>
Bind by setting NUMA locality domain masks on tasks as specified where <list> is
<mask1>,<mask2>,...<maskN>. NUMA locality domain masks are always interpreted as
hexadecimal values but can be preceded with an optional '0x'. Not supported unless
the entire node is allocated to the job.
sockets
Automatically generate masks binding tasks to sockets. Only the CPUs on the socket
which have been allocated to the job will be used. If the number of tasks differs
from the number of allocated sockets this can result in sub-optimal binding.
cores Automatically generate masks binding tasks to cores. If the number of tasks differs
from the number of allocated cores this can result in sub-optimal binding.
threads
Automatically generate masks binding tasks to threads. If the number of tasks
differs from the number of allocated threads this can result in sub-optimal binding.
ldoms Automatically generate masks binding tasks to NUMA locality domains. If the number
of tasks differs from the number of allocated locality domains this can result in
sub-optimal binding.
help Show help message for cpu-bind
This option applies to job and step allocations.
--cpu-freq=<p1>[-p2[:p3]]
Request that the job step initiated by this srun command 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 | SchedUtil | 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 within 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
previous values.
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.
This option applies to job and step allocations.
--cpus-per-gpu=<ncpus>
Advise Slurm that ensuing job steps will require ncpus processors per allocated GPU. Not
compatible with the --cpus-per-task option.
-c, --cpus-per-task=<ncpus>
Request that ncpus be allocated per process. This may be useful if the job is multithreaded and
requires more than one CPU per task for optimal performance. Explicitly requesting this option
implies --exact. The default is one CPU per process and does not imply --exact. If -c is
specified without -n, as many tasks will be allocated per node as possible while satisfying the -c
restriction. For instance on a cluster with 8 CPUs per node, a job request for 4 nodes and 3 CPUs
per task may be allocated 3 or 6 CPUs per node (1 or 2 tasks per node) depending upon resource
consumption by other jobs. Such a job may be unable to execute more than a total of 4 tasks.
WARNING: There are configurations and options interpreted differently by job and job step requests
which can result in inconsistencies for this option. For example srun -c2 --threads-per-core=1
prog may allocate two cores for the job, but if each of those cores contains two threads, the job
allocation will include four CPUs. The job step allocation will then launch two threads per CPU
for a total of two tasks.
WARNING: When srun is executed from within salloc or sbatch, there are configurations and options
which can result in inconsistent allocations when -c has a value greater than -c on salloc or
sbatch.
This option applies to job and step allocations.
--deadline=<OPT>
remove the job if no ending is possible before this deadline (start > (deadline - time[-min])).
Default is no deadline. Valid time formats are:
HH:MM[:SS] [AM|PM]
MMDD[YY] or MM/DD[/YY] or MM.DD[.YY]
MM/DD[/YY]-HH:MM[:SS]
YYYY-MM-DD[THH:MM[:SS]]]
now[+count[seconds(default)|minutes|hours|days|weeks]]
This option applies only to job allocations.
--delay-boot=<minutes>
Do not reboot nodes in order to satisfied this job's feature specification if the job has been
eligible to run for less than this time period. If the job has waited for less than the specified
period, it will use only nodes which already have the specified features. The argument is in
units of minutes. A default value may be set by a system administrator using the delay_boot
option of the SchedulerParameters configuration parameter in the slurm.conf file, otherwise the
default value is zero (no delay).
This option applies only to job allocations.
-d, --dependency=<dependency_list>
Defer the start of this job until the specified dependencies have been satisfied completed. This
option does not apply to job steps (executions of srun within an existing salloc or sbatch
allocation) only to job allocations. <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. Only one separator may be 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. Dependencies on remote jobs are allowed in a federation.
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. This option applies to job allocations.
after:job_id[[+time][:jobid[+time]...]]
After the specified jobs start or are cancelled and 'time' in minutes from job start or
cancellation happens, this job can begin execution. If no 'time' is given then there is no
delay after start or cancellation.
afterany:job_id[:jobid...]
This job can begin execution after the specified jobs have terminated.
afterburstbuffer:job_id[:jobid...]
This job can begin execution after the specified jobs have terminated and any associated
burst buffer stage out operations have completed.
aftercorr:job_id[:jobid...]
A task of this job array can begin execution after the corresponding task ID in the
specified job has completed successfully (ran to completion with an exit code of zero).
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).
singleton
This job can begin execution after any previously launched jobs sharing the same job name
and user have terminated. In other words, only one job by that name and owned by that user
can be running or suspended at any point in time. In a federation, a singleton dependency
must be fulfilled on all clusters unless DependencyParameters=disable_remote_singleton is
used in slurm.conf.
-X, --disable-status
Disable the display of task status when srun receives a single SIGINT (Ctrl-C). Instead
immediately forward the SIGINT to the running job. Without this option a second Ctrl-C in one
second is required to forcibly terminate the job and srun will immediately exit. May also be set
via the environment variable SLURM_DISABLE_STATUS. This option applies to job allocations.
-m,
--distribution={*|block|cyclic|arbitrary|plane=<size>}[:{*|block|cyclic|fcyclic}[:{*|block|cyclic|fcyclic}]][,{Pack|NoPack}]
Specify alternate distribution methods for remote processes. For job allocation, this sets
environment variables that will be used by subsequent srun requests and also affects which cores
will be selected for job allocation.
This option controls the distribution 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 first ":") controls the distribution of tasks to nodes. The
second distribution method (after the first ":") controls the distribution of allocated CPUs
across sockets for binding to tasks. The third distribution method (after the second ":") controls
the distribution of allocated CPUs across cores for binding to tasks. The second and third
distributions apply only if task affinity is enabled. The third distribution is supported only if
the task/cgroup plugin is configured. The default value for each distribution type is specified by
*.
Note that with select/cons_res and select/cons_tres, the number of CPUs allocated to each socket
and node may be different. Refer to https://slurm.schedmd.com/mc_support.html for more information
on resource allocation, distribution of tasks to nodes, and binding of tasks to CPUs.
First distribution method (distribution of tasks across nodes):
* Use the default method for distributing tasks to nodes (block).
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 size <size>. The size must be given or
SLURM_DIST_PLANESIZE must be set. 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.
Additional distribution specifications cannot be combined with this option. For more
details (including examples and diagrams), please see
https://slurm.schedmd.com/mc_support.html and https://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.
NOTE: If the number of tasks is given and a list of requested nodes is also given, the
number of nodes used from that list will be reduced to match that of the number of tasks if
the number of nodes in the list is greater than the number of tasks.
Second distribution method (distribution of CPUs across sockets for binding):
* Use the default method for distributing CPUs across sockets (cyclic).
block The block distribution method will distribute allocated CPUs consecutively from the same
socket for binding to tasks, before using the next consecutive socket.
cyclic The cyclic distribution method will distribute allocated CPUs for binding to a given task
consecutively from the same socket, and from the next consecutive socket for the next task,
in a round-robin fashion across sockets. 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 allocated CPUs for binding to tasks from
consecutive sockets in a round-robin fashion across the sockets. Tasks requiring more than
one CPU will have each CPUs allocated in a cyclic fashion across sockets.
Third distribution method (distribution of CPUs across cores for binding):
* Use the default method for distributing CPUs across cores (inherited from second
distribution method).
block The block distribution method will distribute allocated CPUs consecutively from the same
core for binding to tasks, before using the next consecutive core.
cyclic The cyclic distribution method will distribute allocated CPUs for binding to a given task
consecutively from the same core, and from the next consecutive core for the next task, in
a round-robin fashion across cores.
fcyclic
The fcyclic distribution method will distribute allocated CPUs for binding to tasks from
consecutive cores in a round-robin fashion across the cores.
Optional control for task distribution over nodes:
Pack Rather than evenly distributing a job step's tasks evenly across its allocated nodes, pack
them as tightly as possible on the nodes. This only applies when the "block" task
distribution method is used.
NoPack Rather than packing a job step's tasks as tightly as possible on the nodes, distribute them
evenly. This user option will supersede the SelectTypeParameters CR_Pack_Nodes
configuration parameter.
This option applies to job and step allocations.
--epilog={none|<executable>}
srun will run executable just after the job step completes. The command line arguments for
executable will be the command and arguments of the job step. If none is specified, then no srun
epilog will be run. This parameter overrides the SrunEpilog parameter in slurm.conf. This
parameter is completely independent from the Epilog parameter in slurm.conf. This option applies
to job allocations.
-e, --error=<filename_pattern>
Specify how stderr is to be redirected. By default in interactive mode, srun redirects stderr to
the same file as stdout, if one is specified. The --error option is provided to allow stdout and
stderr to be redirected to different locations. See IO Redirection below for more options. If
the specified file already exists, it will be overwritten. This option applies to job and step
allocations.
--exact
Allow a step access to only the resources requested for the step. By default, all non-GRES
resources on each node in the step allocation will be used. This option only applies to step
allocations.
NOTE: Parallel steps will either be blocked or rejected until requested step resources are
available unless --overlap is specified. Job resources can be held after the completion of an srun
command while Slurm does job cleanup. Step epilogs and/or SPANK plugins can further delay the
release of step resources.
-x, --exclude={<host1[,<host2>...]|<filename>}
Request that a specific list of hosts not be included in the resources allocated to this job. The
host list will be assumed to be a filename if it contains a "/" character. This option applies to
job and step allocations.
--exclusive[={user|mcs}]
This option applies to job and job step allocations, and has two slightly different meanings for
each one. When used to initiate a job, the job allocation cannot share nodes with other running
jobs (or just other users with the "=user" option or "=mcs" option). If user/mcs are not
specified (i.e. the job allocation can not share nodes with other running jobs), the job is
allocated all CPUs and GRES on all nodes in the allocation, but is only allocated as much memory
as it requested. This is by design to support gang scheduling, because suspended jobs still reside
in memory. To request all the memory on a node, use --mem=0. The default shared/exclusive
behavior depends on system configuration and the partition's OverSubscribe option takes precedence
over the job's option.
This option can also be used when initiating more than one job step within an existing resource
allocation (default), where you want separate processors to be dedicated to each job step. If
sufficient processors are not available to initiate the job step, it will be deferred. This can be
thought of as providing a mechanism for resource management to the job within its allocation
(--exact implied).
The exclusive allocation of CPUs applies to job steps by default, but --exact is NOT the default.
In other words, the default behavior is this: job steps will not share CPUs, but job steps will be
allocated all CPUs available to the job on all nodes allocated to the steps.
In order to share the resources use the --overlap option.
See EXAMPLE below.
--export={[ALL,]<environment_variables>|ALL|NONE}
Identify which environment variables from the submission environment are propagated to the
launched application.
--export=ALL
Default mode if --export is not specified. All of the user's environment will be loaded
from the caller's environment.
--export=NONE
None of the user environment will be defined. User must use absolute path to the binary
to be executed that will define the environment. User can not specify explicit
environment variables with "NONE".
This option is particularly important for jobs that are submitted on one cluster and
execute on a different cluster (e.g. with different paths). To avoid steps inheriting
environment export settings (e.g. "NONE") from sbatch command, either set --export=ALL
or the environment variable SLURM_EXPORT_ENV should be set to "ALL".
--export=[ALL,]<environment_variables>
Exports all SLURM* environment variables along with explicitly defined variables.
Multiple environment variable names should be comma separated. Environment variable
names may be specified to propagate the current value (e.g. "--export=EDITOR") or
specific values may be exported (e.g. "--export=EDITOR=/bin/emacs"). If "ALL" is
specified, then all user environment variables will be loaded and will take precedence
over any explicitly given environment variables.
Example: --export=EDITOR,ARG1=test
In this example, the propagated environment will only contain the variable EDITOR from
the user's environment, SLURM_* environment variables, and ARG1=test.
Example: --export=ALL,EDITOR=/bin/emacs
There are two possible outcomes for this example. If the caller has the EDITOR
environment variable defined, then the job's environment will inherit the variable from
the caller's environment. If the caller doesn't have an environment variable defined
for EDITOR, then the job's environment will use the value given by --export.
-B, --extra-node-info=<sockets>[:cores[:threads]]
Restrict node selection to nodes with at least the specified number of sockets, cores per socket
and/or threads per core.
NOTE: These options do not specify the resource allocation size. 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. Values can also be specified as min-max. 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 task/affinity plugin is enabled, then specifying an allocation in this manner also sets a
default --cpu-bind option of threads if the -B option specifies a thread count, otherwise an
option of cores if a core count is specified, otherwise an option of sockets. 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. If not specified, the scontrol show job will
display 'ReqS:C:T=*:*:*'. This option applies to job allocations.
NOTE: This option is mutually exclusive with --hint, --threads-per-core and --ntasks-per-core.
NOTE: If the number of sockets, cores and threads were all specified, the number of nodes was
specified (as a fixed number, not a range) and the number of tasks was NOT specified, srun will
implicitly calculate the number of tasks as one task per thread.
--gid=<group>
If srun is run as root, and the --gid option is used, submit the job with group's group access
permissions. group may be the group name or the numerical group ID. This option applies to job
allocations.
--gpu-bind=[verbose,]<type>
Bind tasks to specific GPUs. By default every spawned task can access every GPU allocated to the
step. If "verbose," is specified before <type>, then print out GPU binding debug information to
the stderr of the tasks. GPU binding is ignored if there is only one task.
Supported type options:
closest Bind each task to the GPU(s) which are closest. In a NUMA environment, each task may be
bound to more than one GPU (i.e. all GPUs in that NUMA environment).
map_gpu:<list>
Bind by setting GPU masks on tasks (or ranks) as specified where <list> is
<gpu_id_for_task_0>,<gpu_id_for_task_1>,... GPU IDs are interpreted as decimal values
unless they are preceded with '0x' in which case they interpreted as hexadecimal values.
If the number of tasks (or ranks) exceeds the number of elements in this list, elements
in the list will be reused as needed starting from the beginning of the list. To
simplify support for large task counts, the lists may follow a map with an asterisk and
repetition count. For example "map_gpu:0*4,1*4". If the task/cgroup plugin is used and
ConstrainDevices is set in cgroup.conf, then the GPU IDs are zero-based indexes relative
to the GPUs allocated to the job (e.g. the first GPU is 0, even if the global ID is 3).
Otherwise, the GPU IDs are global IDs, and all GPUs on each node in the job should be
allocated for predictable binding results.
mask_gpu:<list>
Bind by setting GPU masks on tasks (or ranks) as specified where <list> is
<gpu_mask_for_task_0>,<gpu_mask_for_task_1>,... The mapping is specified for a node and
identical mapping is applied to the tasks on every node (i.e. the lowest task ID on each
node is mapped to the first mask specified in the list, etc.). GPU masks are always
interpreted as hexadecimal values but can be preceded with an optional '0x'. To simplify
support for large task counts, the lists may follow a map with an asterisk and
repetition count. For example "mask_gpu:0x0f*4,0xf0*4". If the task/cgroup plugin is
used and ConstrainDevices is set in cgroup.conf, then the GPU IDs are zero-based indexes
relative to the GPUs allocated to the job (e.g. the first GPU is 0, even if the global
ID is 3). Otherwise, the GPU IDs are global IDs, and all GPUs on each node in the job
should be allocated for predictable binding results.
none Do not bind tasks to GPUs (turns off binding if --gpus-per-task is requested).
per_task:<gpus_per_task>
Each task will be bound to the number of gpus specified in <gpus_per_task>. Gpus are
assigned in order to tasks. The first task will be assigned the first x number of gpus
on the node etc.
single:<tasks_per_gpu>
Like --gpu-bind=closest, except that each task can only be bound to a single GPU, even
when it can be bound to multiple GPUs that are equally close. The GPU to bind to is
determined by <tasks_per_gpu>, where the first <tasks_per_gpu> tasks are bound to the
first GPU available, the second <tasks_per_gpu> tasks are bound to the second GPU
available, etc. This is basically a block distribution of tasks onto available GPUs,
where the available GPUs are determined by the socket affinity of the task and the
socket affinity of the GPUs as specified in gres.conf's Cores parameter.
--gpu-freq=[<type]=value>[,<type=value>][,verbose]
Request that GPUs allocated to the job are configured with specific frequency values. This option
can be used to independently configure the GPU and its memory frequencies. After the job is
completed, the frequencies of all affected GPUs will be reset to the highest possible values. In
some cases, system power caps may override the requested values. The field type can be "memory".
If type is not specified, the GPU frequency is implied. The value field can either be "low",
"medium", "high", "highm1" or a numeric value in megahertz (MHz). If the specified numeric value
is not possible, a value as close as possible will be used. See below for definition of the
values. The verbose option causes current GPU frequency information to be logged. Examples of
use include "--gpu-freq=medium,memory=high" and "--gpu-freq=450".
Supported value definitions:
low the lowest available frequency.
medium attempts to set a frequency in the middle of the available range.
high the highest available frequency.
highm1 (high minus one) will select the next highest available frequency.
-G, --gpus=[type:]<number>
Specify the total number of GPUs required for the job. An optional GPU type specification can be
supplied. For example "--gpus=volta:3". Multiple options can be requested in a comma separated
list, for example: "--gpus=volta:3,kepler:1". See also the --gpus-per-node, --gpus-per-socket and
--gpus-per-task options.
--gpus-per-node=[type:]<number>
Specify the number of GPUs required for the job on each node included in the job's resource
allocation. An optional GPU type specification can be supplied. For example
"--gpus-per-node=volta:3". Multiple options can be requested in a comma separated list, for
example: "--gpus-per-node=volta:3,kepler:1". See also the --gpus, --gpus-per-socket and
--gpus-per-task options.
--gpus-per-socket=[type:]<number>
Specify the number of GPUs required for the job on each socket included in the job's resource
allocation. An optional GPU type specification can be supplied. For example
"--gpus-per-socket=volta:3". Multiple options can be requested in a comma separated list, for
example: "--gpus-per-socket=volta:3,kepler:1". Requires job to specify a sockets per node count (
--sockets-per-node). See also the --gpus, --gpus-per-node and --gpus-per-task options. This
option applies to job allocations.
--gpus-per-task=[type:]<number>
Specify the number of GPUs required for the job on each task to be spawned in the job's resource
allocation. An optional GPU type specification can be supplied. For example
"--gpus-per-task=volta:1". Multiple options can be requested in a comma separated list, for
example: "--gpus-per-task=volta:3,kepler:1". See also the --gpus, --gpus-per-socket and
--gpus-per-node options. This option requires an explicit task count, e.g. -n, --ntasks or
"--gpus=X --gpus-per-task=Y" rather than an ambiguous range of nodes with -N, --nodes. This
option will implicitly set --gpu-bind=per_task:<gpus_per_task>, but that can be overridden with an
explicit --gpu-bind specification.
--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 count can have a suffix of "k" or "K"
(multiple of 1024), "m" or "M" (multiple of 1024 x 1024), "g" or "G" (multiple of 1024 x 1024 x
1024), "t" or "T" (multiple of 1024 x 1024 x 1024 x 1024), "p" or "P" (multiple of 1024 x 1024 x
1024 x 1024 x 1024). 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", "--gres=gpu:kepler:2", and
"--gres=help". NOTE: This option applies to job and step allocations. By default, a job step is
allocated all of the generic resources that have been allocated to the job. To change the
behavior so that each job step is allocated no generic resources, explicitly set the value of
--gres to specify zero counts for each generic resource OR set "--gres=none" OR set the
SLURM_STEP_GRES environment variable to "none".
--gres-flags=<type>
Specify generic resource task binding options. This option applies to job allocations.
disable-binding
Disable filtering of CPUs with respect to generic resource locality. This option is
currently required to use more CPUs than are bound to a GRES (i.e. if a GPU is bound to the
CPUs on one socket, but resources on more than one socket are required to run the job).
This option may permit a job to be allocated resources sooner than otherwise possible, but
may result in lower job performance.
NOTE: This option is specific to SelectType=cons_res.
enforce-binding
The only CPUs available to the job will be those bound to the selected GRES (i.e. the CPUs
identified in the gres.conf file will be strictly enforced). This option may result in
delayed initiation of a job. For example a job requiring two GPUs and one CPU will be
delayed until both GPUs on a single socket are available rather than using GPUs bound to
separate sockets, however, the application performance may be improved due to improved
communication speed. Requires the node to be configured with more than one socket and
resource filtering will be performed on a per-socket basis.
NOTE: This option is specific to SelectType=cons_tres.
-h, --help
Display help information and exit.
--het-group=<expr>
Identify each component in a heterogeneous job allocation for which a step is to be created.
Applies only to srun commands issued inside a salloc allocation or sbatch script. <expr> is a set
of integers corresponding to one or more options offsets on the salloc or sbatch command line.
Examples: "--het-group=2", "--het-group=0,4", "--het-group=1,3-5". The default value is
--het-group=0.
--hint=<type>
Bind tasks according to application hints.
NOTE: This option cannot be used in conjunction with any of --ntasks-per-core, --threads-per-core,
--cpu-bind (other than --cpu-bind=verbose) or -B. If --hint is specified as a command line
argument, it will take precedence over the environment.
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
This option applies to job allocations.
-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>"). This option
applies to job allocations.
-I, --immediate[=<seconds>]
exit if resources are not available within the time period specified. If no argument is given
(seconds defaults to 1), resources must be available immediately for the request to succeed. If
defer is configured in SchedulerParameters and seconds=1 the allocation request will fail
immediately; defer conflicts and takes precedence over this option. 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". This option applies to
job and step allocations.
-i, --input=<mode>
Specify how stdin is to redirected. By default, srun redirects stdin from the terminal all tasks.
See IO Redirection below for more options. For OS X, the poll() function does not support stdin,
so input from a terminal is not possible. This option applies to job and step allocations.
-J, --job-name=<jobname>
Specify a name for the job. The specified name will appear along with the job id number when
querying running jobs on the system. The default is the supplied executable program's name. NOTE:
This information may be written to the slurm_jobacct.log file. This file is space delimited so if
a space is used in the jobname name it will cause problems in properly displaying the contents of
the slurm_jobacct.log file when the sacct command is used. This option applies to job and step
allocations.
--jobid=<jobid>
Initiate a job step under an already allocated job with job id id. Using this option will cause
srun to behave exactly as if the SLURM_JOB_ID environment variable was set. This option applies to
step allocations.
-K, --kill-on-bad-exit[=0|1]
Controls whether or not to terminate a step if any task exits with a non-zero exit code. If this
option is not specified, the default action will be based upon the Slurm configuration parameter
of KillOnBadExit. If this option is specified, it will take precedence over KillOnBadExit. An
option argument of zero will not terminate the job. A non-zero argument or no argument will
terminate the job. Note: This option takes precedence over the -W, --wait option to terminate the
job immediately if a task exits with a non-zero exit code. 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".
-l, --label
Prepend task number to lines of stdout/err. The --label option will prepend lines of output with
the remote task id. This option applies to step allocations.
-L, --licenses=<license>[@db][:count][,license[@db][:count]...]
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"). This
option applies to job allocations.
--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, INVALID_DEPEND, REQUEUE, and STAGE_OUT),
INVALID_DEPEND (dependency never satisfied), STAGE_OUT (burst buffer stage out and teardown
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. This option applies to job allocations.
--mail-user=<user>
User to receive email notification of state changes as defined by --mail-type. The default value
is the submitting user. This option applies to job allocations.
--mcs-label=<mcs>
Used only when the mcs/group plugin is enabled. This parameter is a group among the groups of the
user. Default value is calculated by the Plugin mcs if it's enabled. This option applies to job
allocations.
--mem=<size>[units]
Specify the real memory required per node. Default units are megabytes. Different units can be
specified using the suffix [K|M|G|T]. 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). Specifying a memory limit of zero for a job step will restrict the
job step to the amount of memory allocated to the job, but not remove any of the job's memory
allocation from being available to other job steps. Also see --mem-per-cpu and --mem-per-gpu.
The --mem, --mem-per-cpu and --mem-per-gpu options are mutually exclusive. If --mem, --mem-per-cpu
or --mem-per-gpu are specified as command line arguments, then they will take precedence over the
environment (potentially inherited from salloc or sbatch).
NOTE: A memory size specification of zero is treated as a special case and grants the job access
to all of the memory on each node for newly submitted jobs and all available job memory to new job
steps.
Specifying new memory limits for job steps are only advisory.
If the job is allocated multiple nodes in a heterogeneous cluster, the memory limit on each node
will be that of the node in the allocation with the smallest memory size (same limit will apply to
every node in the job's allocation).
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.
This option applies to job and step allocations.
--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. By default no memory binding is performed; any task
using any CPU can use any memory. This option is typically used to ensure that each task is bound
to the memory closest to its assigned CPU. 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
"--cpu-bind=verbose,none --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_LIST
SLURM_MEM_BIND_PREFER
SLURM_MEM_BIND_SORT
SLURM_MEM_BIND_TYPE
SLURM_MEM_BIND_VERBOSE
See the ENVIRONMENT VARIABLES section for a more detailed description of the individual
SLURM_MEM_BIND* variables.
Supported options include:
help show this help message
local Use memory local to the processor in use
map_mem:<list>
Bind by setting memory masks on tasks (or ranks) as specified where <list> is
<numa_id_for_task_0>,<numa_id_for_task_1>,... The mapping is specified for a node and
identical mapping is applied to the tasks on every node (i.e. the lowest task ID on each
node is mapped to the first ID specified in the list, etc.). NUMA IDs are interpreted as
decimal values unless they are preceded with '0x' in which case they interpreted as
hexadecimal values. If the number of tasks (or ranks) exceeds the number of elements in
this list, elements in the list will be reused as needed starting from the beginning of the
list. To simplify support for large task counts, the lists may follow a map with an
asterisk and repetition count. For example "map_mem:0x0f*4,0xf0*4". For predictable
binding results, all CPUs for each node in the job should be allocated to the job.
mask_mem:<list>
Bind by setting memory masks on tasks (or ranks) as specified where <list> is
<numa_mask_for_task_0>,<numa_mask_for_task_1>,... The mapping is specified for a node and
identical mapping is applied to the tasks on every node (i.e. the lowest task ID on each
node is mapped to the first mask specified in the list, etc.). NUMA 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. If the number of tasks (or
ranks) exceeds the number of elements in this list, elements in the list will be reused as
needed starting from the beginning of the list. To simplify support for large task counts,
the lists may follow a mask with an asterisk and repetition count. For example
"mask_mem:0*4,1*4". For predictable binding results, all CPUs for each node in the job
should be allocated to the job.
no[ne] don't bind tasks to memory (default)
nosort avoid sorting free cache pages (default, LaunchParameters configuration parameter can
override this default)
p[refer]
Prefer use of first specified NUMA node, but permit
use of other available NUMA nodes.
q[uiet]
quietly bind before task runs (default)
rank bind by task rank (not recommended)
sort sort free cache pages (run zonesort on Intel KNL nodes)
v[erbose]
verbosely report binding before task runs
This option applies to job and step allocations.
--mem-per-cpu=<size>[units]
Minimum memory required per allocated CPU. Default units are megabytes. Different units can be
specified using the suffix [K|M|G|T]. The default value is DefMemPerCPU and the maximum value is
MaxMemPerCPU (see exception below). If configured, both 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 core, socket, or
whole nodes, then 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. Specifying a memory limit of zero for a
job step will restrict the job step to the amount of memory allocated to the job, but not remove
any of the job's memory allocation from being available to other job steps. Also see --mem and
--mem-per-gpu. The --mem, --mem-per-cpu and --mem-per-gpu options are mutually exclusive.
NOTE: If the final amount of memory requested by a job can't be satisfied by any of the nodes
configured in the partition, the job will be rejected. This could happen if --mem-per-cpu is used
with the --exclusive option for a job allocation and --mem-per-cpu times the number of CPUs on a
node is greater than the total memory of that node.
--mem-per-gpu=<size>[units]
Minimum memory required per allocated GPU. Default units are megabytes. Different units can be
specified using the suffix [K|M|G|T]. Default value is DefMemPerGPU and is available on both a
global and per partition basis. If configured, the parameters can be seen using the scontrol show
config and scontrol show partition commands. Also see --mem. The --mem, --mem-per-cpu and
--mem-per-gpu options are mutually exclusive.
--mincpus=<n>
Specify a minimum number of logical cpus/processors per node. This option applies to job
allocations.
--mpi=<mpi_type>
Identify the type of MPI to be used. May result in unique initiation procedures.
list Lists available mpi types to choose from.
pmi2 To enable PMI2 support. The PMI2 support in Slurm works only if the MPI implementation
supports it, in other words if the MPI has the PMI2 interface implemented. The --mpi=pmi2
will load the library lib/slurm/mpi_pmi2.so which provides the server side functionality
but the client side must implement PMI2_Init() and the other interface calls.
pmix To enable PMIx support (https://pmix.github.io). The PMIx support in Slurm can be used to
launch parallel applications (e.g. MPI) if it supports PMIx, PMI2 or PMI1. Slurm must be
configured with pmix support by passing "--with-pmix=<PMIx installation path>" option to
its "./configure" script.
At the time of writing PMIx is supported in Open MPI starting from version 2.0. PMIx also
supports backward compatibility with PMI1 and PMI2 and can be used if MPI was configured
with PMI2/PMI1 support pointing to the PMIx library ("libpmix"). If MPI supports PMI1/PMI2
but doesn't provide the way to point to a specific implementation, a hack'ish solution
leveraging LD_PRELOAD can be used to force "libpmix" usage.
none No special MPI processing. This is the default and works with many other versions of MPI.
This option applies to step allocations.
--msg-timeout=<seconds>
Modify the job launch message timeout. The default value is MessageTimeout in the Slurm
configuration file slurm.conf. Changes to this are typically not recommended, but could be useful
to diagnose problems. This option applies to job allocations.
--multi-prog
Run a job with different programs and different arguments for each task. In this case, the
executable program specified is actually a configuration file specifying the executable and
arguments for each task. See MULTIPLE PROGRAM CONFIGURATION below for details on the configuration
file contents. This option applies to step allocations.
--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 Performance 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 and the step cannot specify
the --overlap 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. 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.
CAU=<count> Number of Collective 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).
This option applies to job and step allocations.
--nice[=adjustment]
Run the job with an adjusted scheduling priority within Slurm. With no adjustment value the
scheduling priority is decreased by 100. A negative nice value increases the priority, otherwise
decreases it. The adjustment range is +/- 2147483645. Only privileged users can specify a negative
adjustment.
-Z, --no-allocate
Run the specified tasks on a set of nodes without creating a Slurm "job" in the Slurm queue
structure, bypassing the normal resource allocation step. The list of nodes must be specified
with the -w, --nodelist option. This is a privileged option only available for the users
"SlurmUser" and "root". This option applies to job allocations.
-k, --no-kill[=off]
Do not automatically terminate a job if one of the nodes it has been allocated fails. This option
applies to job and step allocations. The job will assume all responsibilities for
fault-tolerance. Tasks launch using this option will not be considered terminated (e.g. -K,
--kill-on-bad-exit and -W, --wait options will have no effect upon the job step). The active job
step (MPI job) will likely suffer a fatal error, but subsequent job steps may be run if this
option is specified.
Specify an optional argument of "off" disable the effect of the SLURM_NO_KILL environment
variable.
The default action is to terminate the job upon node failure.
-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.
-w, --nodelist={<node_name_list>|<filename>}
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. Rather than repeating a host name multiple times, an
asterisk and a repetition count may be appended to a host name. For example "host1,host1" and
"host1*2" are equivalent. If the number of tasks is given and a list of requested nodes is also
given, the number of nodes used from that list will be reduced to match that of the number of
tasks if the number of nodes in the list is greater than the number of tasks. This option applies
to job and step allocations.
-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_JOB_NUM_NODES (and SLURM_NNODES for
backwards compatibility) 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. If the number of tasks is given and a number of requested nodes is also given, the
number of nodes used from that request will be reduced to match that of the number of tasks if the
number of nodes in the request is greater than the number of tasks. 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). This option applies to job and step allocations.
-n, --ntasks=<number>
Specify the number of tasks to run. Request that srun allocate resources for ntasks tasks. The
default is one task per node, but note that the --cpus-per-task option will change this default.
This option applies to job and step allocations.
--ntasks-per-core=<ntasks>
Request the maximum ntasks be invoked on each core. This option applies to the job allocation,
but not to step allocations. Meant to be used with the --ntasks option. Related to
--ntasks-per-node except at the core level instead of the node level. Masks will automatically be
generated to bind the tasks to specific cores unless --cpu-bind=none is specified. NOTE: This
option is not supported when using SelectType=select/linear.
--ntasks-per-gpu=<ntasks>
Request that there are ntasks tasks invoked for every GPU. This option can work in two ways: 1)
either specify --ntasks in addition, in which case a type-less GPU specification will be
automatically determined to satisfy --ntasks-per-gpu, or 2) specify the GPUs wanted (e.g. via
--gpus or --gres) without specifying --ntasks, and the total task count will be automatically
determined. The number of CPUs needed will be automatically increased if necessary to allow for
any calculated task count. This option will implicitly set --gpu-bind=single:<ntasks>, but that
can be overridden with an explicit --gpu-bind specification. This option is not compatible with a
node range (i.e. -N<minnodes-maxnodes>). This option is not compatible with --gpus-per-task,
--gpus-per-socket, or --ntasks-per-node. This option is not supported unless SelectType=cons_tres
is configured (either directly or indirectly on Cray systems).
--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. This option applies to job
allocations.
--ntasks-per-socket=<ntasks>
Request the maximum ntasks be invoked on each socket. This option applies to the job allocation,
but not to step allocations. Meant to be used with the --ntasks option. Related to
--ntasks-per-node except at the socket level instead of the node level. Masks will automatically
be generated to bind the tasks to specific sockets unless --cpu-bind=none is specified. NOTE:
This option is not supported when using SelectType=select/linear.
--open-mode={append|truncate}
Open the output and error files using append or truncate mode as specified. For heterogeneous job
steps the default value is "append". Otherwise the default value is specified by the system
configuration parameter JobFileAppend. This option applies to job and step allocations.
-o, --output=<filename_pattern>
Specify the "filename pattern" for stdout redirection. By default in interactive mode, srun
collects stdout from all tasks and sends this output via TCP/IP to the attached terminal. With
--output stdout may be redirected to a file, to one file per task, or to /dev/null. See section IO
Redirection below for the various forms of filename pattern. If the specified file already
exists, it will be overwritten.
If --error is not also specified on the command line, both stdout and stderr will directed to the
file specified by --output. This option applies to job and step allocations.
-O, --overcommit
Overcommit resources. This option applies to job and step allocations.
When applied to a job allocation (not including jobs requesting exclusive access to the nodes) the
resources are allocated as if only one task per node is requested. This means that the requested
number of cpus per task (-c, --cpus-per-task) are allocated per node rather than being multiplied
by the number of tasks. 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.
--overlap
Allow steps to overlap each other on the CPUs. By default steps do not share CPUs with other
parallel steps.
-s, --oversubscribe
The job allocation can over-subscribe resources with other running jobs. The resources to be
over-subscribed can be nodes, sockets, cores, and/or hyperthreads depending upon configuration.
The default over-subscribe behavior depends on system configuration and the partition's
OverSubscribe option takes precedence over the job's option. This option may result in the
allocation being granted sooner than if the --oversubscribe option was not set and allow higher
system utilization, but application performance will likely suffer due to competition for
resources. This option applies to step allocations.
-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.
This option applies to job allocations.
--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). This option applies to job allocations.
-E, --preserve-env
Pass the current values of environment variables SLURM_JOB_NUM_NODES and SLURM_NTASKS through to
the executable, rather than computing them from command line parameters. This option applies to
job allocations.
--priority=<value>
Request a specific job priority. May be subject to configuration specific constraints. value
should either be a numeric value or "TOP" (for highest possible value). Only Slurm operators and
administrators can set the priority of a job. This option applies to job allocations only.
--profile={all|none|<type>[,<type>...]}
Enables detailed data collection by the acct_gather_profile plugin. Detailed data are typically
time-series that are stored in an HDF5 file for the job or an InfluxDB database depending on the
configured plugin. This option applies to job and step allocations.
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.)
Valid type values are:
Energy Energy data is collected.
Task Task (I/O, Memory, ...) data is collected.
Filesystem
Filesystem data is collected.
Network
Network (InfiniBand) data is collected.
--prolog=<executable>
srun will run executable just before launching the job step. The command line arguments for
executable will be the command and arguments of the job step. If executable is "none", then no
srun prolog will be run. This parameter overrides the SrunProlog parameter in slurm.conf. This
parameter is completely independent from the Prolog parameter in slurm.conf. This option applies
to job allocations.
--propagate[=rlimit[,rlimit...]]
Allows users to specify which of the modifiable (soft) resource limits to propagate to the compute
nodes and apply to their jobs. If no rlimit is specified, then all resource limits will be
propagated. The following rlimit names are supported by Slurm (although some options may not be
supported on some systems):
ALL All limits listed below (default)
NONE No limits listed below
AS The maximum address space (virtual memory) for a process.
CORE The maximum size of core file
CPU The maximum amount of CPU time
DATA The maximum size of a process's data segment
FSIZE The maximum size of files created. Note that if the user sets FSIZE to less than the
current size of the slurmd.log, job launches will fail with a 'File size limit exceeded'
error.
MEMLOCK The maximum size that may be locked into memory
NOFILE The maximum number of open files
NPROC The maximum number of processes available
RSS The maximum resident set size. Note that this only has effect with Linux kernels 2.4.30
or older or BSD.
STACK The maximum stack size
This option applies to job allocations.
--pty Execute task zero in pseudo terminal mode. Implicitly sets --unbuffered. Implicitly sets --error
and --output to /dev/null for all tasks except task zero, which may cause those tasks to exit
immediately (e.g. shells will typically exit immediately in that situation). This option applies
to step allocations.
-q, --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 its
definition. This option applies to job allocations.
-Q, --quiet
Suppress informational messages from srun. Errors will still be displayed. This option applies to
job and step allocations.
--quit-on-interrupt
Quit immediately on single SIGINT (Ctrl-C). Use of this option disables the status feature
normally available when srun receives a single Ctrl-C and causes srun to instead immediately
terminate the running job. This option applies to step allocations.
--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. Only root, SlurmUser or admins can
reboot nodes. This option applies to job allocations.
-r, --relative=<n>
Run a job step relative to node n of the current allocation. This option may be used to spread
several job steps out among the nodes of the current job. If -r is used, the current job step will
begin at node n of the allocated nodelist, where the first node is considered node 0. The -r
option is not permitted with -w or -x option and will result in a fatal error when not running
within a prior allocation (i.e. when SLURM_JOB_ID is not set). The default for n is 0. If the
value of --nodes exceeds the number of nodes identified with the --relative option, a warning
message will be printed and the --relative option will take precedence. This option applies to
step allocations.
--reservation=<reservation_names>
Allocate resources for the job from the named reservation. If the job can use more than one
reservation, specify their names in a comma separate list and the one offering earliest
initiation. Each reservation will be considered in the order it was requested. All reservations
will be listed in scontrol/squeue through the life of the job. In accounting the first
reservation will be seen and after the job starts the reservation used will replace it.
--resv-ports[=count]
Reserve communication ports for this job. Users can specify the number of port they want to
reserve. The parameter MpiParams=ports=12000-12999 must be specified in slurm.conf. If not
specified and Slurm's OpenMPI plugin is used, then by default the number of reserved equal to the
highest number of tasks on any node in the job step allocation. If the number of reserved ports
is zero then no ports is reserved. Used for OpenMPI. This option applies to job and step
allocations.
--send-libs[=yes|no]
If set to yes (or no argument), autodetect and broadcast the executable's shared object
dependencies to allocated compute nodes. The files are placed in a directory alongside the
executable. The LD_LIBRARY_PATH is automatically updated to include this cache directory as well.
This overrides the default behavior configured in slurm.conf SbcastParameters send_libs. This
option only works in conjunction with --bcast. See also --bcast-exclude.
--signal=[R:]<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. This
option applies to job allocations. Use the "R:" option to allow this job to overlap with a
reservation with MaxStartDelay set. To have the signal sent at preemption time see the
preempt_send_user_signal SlurmctldParameter.
--slurmd-debug=<level>
Specify a debug level for slurmd(8). The level may be specified either an integer value between 0
[quiet, only errors are displayed] and 4 [verbose operation] or the SlurmdDebug tags.
quiet Log nothing
fatal Log only fatal errors
error Log only errors
info Log errors and general informational messages
verbose Log errors and verbose informational messages
The slurmd debug information is copied onto the stderr of the job. By default only errors are
displayed. This option applies to job and step allocations.
--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. This option applies to job
allocations.
NOTE: This option may implicitly impact the number of tasks if -n was not specified.
--spread-job
Spread the job allocation over as many nodes as possible and attempt to evenly distribute tasks
across the allocated nodes. This option disables the topology/tree plugin. This option applies
to job allocations.
--switches=<count>[@max-time]
When a tree topology is used, this defines the maximum count of leaf 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. On a dragonfly network the only switch count supported is 1 since communication
performance will be highest when a job is allocate resources on one leaf switch or more than 2
leaf switches. The default max-time is the max_switch_wait SchedulerParameters. This option
applies to job allocations.
--task-epilog=<executable>
The slurmstepd daemon will run executable just after each task terminates. This will be executed
before any TaskEpilog parameter in slurm.conf is executed. This is meant to be a very short-lived
program. If it fails to terminate within a few seconds, it will be killed along with any
descendant processes. This option applies to step allocations.
--task-prolog=<executable>
The slurmstepd daemon will run executable just before launching each task. This will be executed
after any TaskProlog parameter in slurm.conf is executed. Besides the normal environment
variables, this has SLURM_TASK_PID available to identify the process ID of the task being started.
Standard output from this program of the form "export NAME=value" will be used to set environment
variables for the task being spawned. This option applies to step allocations.
--test-only
Returns an estimate of when a job would be scheduled to run given the current job queue and all
the other srun arguments specifying the job. This limits srun's behavior to just return
information; no job is actually submitted. The program will be executed directly by the slurmd
daemon. This option applies to job allocations.
--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. This option applies to job
allocations.
-T, --threads=<nthreads>
Allows limiting the number of concurrent threads used to send the job request from the srun
process to the slurmd processes on the allocated nodes. Default is to use one thread per allocated
node up to a maximum of 60 concurrent threads. Specifying this option limits the number of
concurrent threads to nthreads (less than or equal to 60). This should only be used to set a low
thread count for testing on very small memory computers. This option applies to job allocations.
--threads-per-core=<threads>
Restrict node selection to nodes with at least the specified number of threads per core. In task
layout, use the specified maximum number of threads per core. Implies --exact and
--cpu-bind=threads unless overridden by command line or environment options. 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. This option applies to job and step allocations.
NOTE: This option may implicitly impact the number of tasks if -n was not specified.
-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". This option applies to job and step allocations.
--time-min=<time>
Set a minimum time limit on the job allocation. If specified, the job may have its --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". This
option applies to job allocations.
--tmp=<size>[units]
Specify a minimum amount of temporary disk space per node. Default units are megabytes.
Different units can be specified using the suffix [K|M|G|T]. This option applies to job
allocations.
--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. User root may use
this option to run jobs as a normal user in a RootOnly partition for example. If run as root, srun
will drop its permissions to the uid specified after node allocation is successful. user may be
the user name or numerical user ID. This option applies to job and step allocations.
-u, --unbuffered
By default, the connection between slurmstepd and the user-launched application is over a pipe.
The stdio output written by the application is buffered by the glibc until it is flushed or the
output is set as unbuffered. See setbuf(3). If this option is specified the tasks are executed
with a pseudo terminal so that the application output is unbuffered. This option applies to step
allocations.
--usage
Display brief help message and exit.
--use-min-nodes
If a range of node counts is given, prefer the smaller count.
-v, --verbose
Increase the verbosity of srun's informational messages. Multiple -v's will further increase
srun's verbosity. By default only errors will be displayed. This option applies to job and step
allocations.
-V, --version
Display version information and exit.
-W, --wait=<seconds>
Specify how long to wait after the first task terminates before terminating all remaining tasks. A
value of 0 indicates an unlimited wait (a warning will be issued after 60 seconds). The default
value is set by the WaitTime parameter in the slurm configuration file (see slurm.conf(5)). This
option can be useful to ensure that a job is terminated in a timely fashion in the event that one
or more tasks terminate prematurely. Note: The -K, --kill-on-bad-exit option takes precedence
over -W, --wait to terminate the job immediately if a task exits with a non-zero exit code. This
option applies to job allocations.
--wckey=<wckey>
Specify wckey to be used with job. If TrackWCKey=no (default) in the slurm.conf this value is
ignored. This option applies to job allocations.
--x11[={all|first|last}]
Sets up X11 forwarding on "all", "first" or "last" node(s) of the allocation. This option is only
enabled if Slurm was compiled with X11 support and PrologFlags=x11 is defined in the slurm.conf.
Default is "all".
srun will submit the job request to the slurm job controller, then initiate all processes on the remote
nodes. If the request cannot be met immediately, srun will block until the resources are free to run the
job. If the -I (--immediate) option is specified srun will terminate if resources are not immediately
available.
When initiating remote processes srun will propagate the current working directory, unless --chdir=<path>
is specified, in which case path will become the working directory for the remote processes.
The -n, -c, and -N options control how CPUs and nodes will be allocated to the job. When specifying only
the number of processes to run with -n, a default of one CPU per process is allocated. By specifying the
number of CPUs required per task (-c), more than one CPU may be allocated per process. If the number of
nodes is specified with -N, srun will attempt to allocate at least the number of nodes specified.
Combinations of the above three options may be used to change how processes are distributed across nodes
and cpus. For instance, by specifying both the number of processes and number of nodes on which to run,
the number of processes per node is implied. However, if the number of CPUs per process is more important
then number of processes (-n) and the number of CPUs per process (-c) should be specified.
srun will refuse to allocate more than one process per CPU unless --overcommit (-O) is also specified.
srun will attempt to meet the above specifications "at a minimum." That is, if 16 nodes are requested for
32 processes, and some nodes do not have 2 CPUs, the allocation of nodes will be increased in order to
meet the demand for CPUs. In other words, a minimum of 16 nodes are being requested. However, if 16 nodes
are requested for 15 processes, srun will consider this an error, as 15 processes cannot run across 16
nodes.
IO Redirection
By default, stdout and stderr will be redirected from all tasks to the stdout and stderr of srun, and
stdin will be redirected from the standard input of srun to all remote tasks. If stdin is only to be
read by a subset of the spawned tasks, specifying a file to read from rather than forwarding stdin from
the srun command may be preferable as it avoids moving and storing data that will never be read.
For OS X, the poll() function does not support stdin, so input from a terminal is not possible.
This behavior may be changed with the --output, --error, and --input (-o, -e, -i) options. Valid format
specifications for these options are
all stdout stderr is redirected from all tasks to srun. stdin is broadcast to all remote tasks.
(This is the default behavior)
none stdout and stderr is not received from any task. stdin is not sent to any task (stdin is
closed).
taskid stdout and/or stderr are redirected from only the task with relative id equal to taskid, where
0 <= taskid <= ntasks, where ntasks is the total number of tasks in the current job step.
stdin is redirected from the stdin of srun to this same task. This file will be written on the
node executing the task.
filename srun will redirect stdout and/or stderr to the named file from all tasks. stdin will be
redirected from the named file and broadcast to all tasks in the job. filename refers to a
path on the host that runs srun. Depending on the cluster's file system layout, this may
result in the output appearing in different places depending on whether the job is run in batch
mode.
filename pattern
srun allows for a filename pattern to be used to generate the named IO file described above.
The following list of format specifiers may be used in the format string to generate a filename
that will be unique to a given jobid, stepid, node, or task. In each case, the appropriate
number of files are opened and associated with the corresponding tasks. Note that any format
string containing %t, %n, and/or %N will be written on the node executing the task rather than
the node where srun executes, these format specifiers are not supported on a BGQ system.
\\ Do not process any of the replacement symbols.
%% The character "%".
%A Job array's master job allocation number.
%a Job array ID (index) number.
%J jobid.stepid of the running job. (e.g. "128.0")
%j jobid of the running job.
%s stepid of the running job.
%N short hostname. This will create a separate IO file per node.
%n Node identifier relative to current job (e.g. "0" is the first node of the running job)
This will create a separate IO file per node.
%t task identifier (rank) relative to current job. This will create a separate IO file per
task.
%u User name.
%x Job name.
A number placed between the percent character and format specifier may be used to zero-pad the
result in the IO filename. This number is ignored if the format specifier corresponds to
non-numeric data (%N for example).
Some examples of how the format string may be used for a 4 task job step with a Job ID of 128
and step id of 0 are included below:
job%J.out job128.0.out
job%4j.out job0128.out
job%j-%2t.out job128-00.out, job128-01.out, ...
PERFORMANCE
Executing srun sends a remote procedure call to slurmctld. If enough calls from srun or other Slurm
client commands that send remote procedure calls to the slurmctld daemon come in at once, it can result
in a degradation of performance of the slurmctld daemon, possibly resulting in a denial of service.
Do not run srun or other Slurm client commands that send remote procedure calls to slurmctld from loops
in shell scripts or other programs. Ensure that programs limit calls to srun to the minimum necessary for
the information you are trying to gather.
INPUT ENVIRONMENT VARIABLES
Upon startup, srun will read and handle the options set in the following environment variables. The
majority of these variables are set the same way the options are set, as defined above. For flag options
that are defined to expect no argument, the option can be enabled by setting the environment variable
without a value (empty or NULL string), the string 'yes', or a non-zero number. Any other value for the
environment variable will result in the option not being set. There are a couple exceptions to these
rules that are noted below.
NOTE: Command line options always override environment variable settings.
PMI_FANOUT This is used exclusively with PMI (MPICH2 and MVAPICH2) and controls the fanout of
data communications. The srun command sends messages to application programs (via
the PMI library) and those applications may be called upon to forward that data to
up to this number of additional tasks. Higher values offload work from the srun
command to the applications and likely increase the vulnerability to failures. The
default value is 32.
PMI_FANOUT_OFF_HOST This is used exclusively with PMI (MPICH2 and MVAPICH2) and controls the fanout of
data communications. The srun command sends messages to application programs (via
the PMI library) and those applications may be called upon to forward that data to
additional tasks. By default, srun sends one message per host and one task on that
host forwards the data to other tasks on that host up to PMI_FANOUT. If
PMI_FANOUT_OFF_HOST is defined, the user task may be required to forward the data
to tasks on other hosts. Setting PMI_FANOUT_OFF_HOST may increase performance.
Since more work is performed by the PMI library loaded by the user application,
failures also can be more common and more difficult to diagnose. Should be
disabled/enabled by setting to 0 or 1.
PMI_TIME This is used exclusively with PMI (MPICH2 and MVAPICH2) and controls how much the
communications from the tasks to the srun are spread out in time in order to avoid
overwhelming the srun command with work. The default value is 500 (microseconds)
per task. On relatively slow processors or systems with very large processor counts
(and large PMI data sets), higher values may be required.
SLURM_ACCOUNT Same as -A, --account
SLURM_ACCTG_FREQ Same as --acctg-freq
SLURM_BCAST Same as --bcast
SLURM_BCAST_EXCLUDE Same as --bcast-exclude
SLURM_BURST_BUFFER Same as --bb
SLURM_CLUSTERS Same as -M, --clusters
SLURM_COMPRESS Same as --compress
SLURM_CONF The location of the Slurm configuration file.
SLURM_CONSTRAINT Same as -C, --constraint
SLURM_CORE_SPEC Same as --core-spec
SLURM_CPU_BIND Same as --cpu-bind
SLURM_CPU_FREQ_REQ Same as --cpu-freq.
SLURM_CPUS_PER_GPU Same as --cpus-per-gpu
SLURM_CPUS_PER_TASK Same as -c, --cpus-per-task
SLURM_DEBUG Same as -v, --verbose. Must be set to 0 or 1 to disable or enable the option.
SLURM_DELAY_BOOT Same as --delay-boot
SLURM_DEPENDENCY Same as -d, --dependency=<jobid>
SLURM_DISABLE_STATUS Same as -X, --disable-status
SLURM_DIST_PLANESIZE Plane distribution size. Only used if --distribution=plane, without =<size>, is
set.
SLURM_DISTRIBUTION Same as -m, --distribution
SLURM_EPILOG Same as --epilog
SLURM_EXACT Same as --exact
SLURM_EXCLUSIVE Same as --exclusive
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.
SLURM_EXPORT_ENV Same as --export
SLURM_GPU_BIND Same as --gpu-bind
SLURM_GPU_FREQ Same as --gpu-freq
SLURM_GPUS Same as -G, --gpus
SLURM_GPUS_PER_NODE Same as --gpus-per-node
SLURM_GPUS_PER_TASK Same as --gpus-per-task
SLURM_GRES Same as --gres. Also see SLURM_STEP_GRES
SLURM_GRES_FLAGS Same as --gres-flags
SLURM_HINT Same as --hint
SLURM_IMMEDIATE Same as -I, --immediate
SLURM_JOB_ID Same as --jobid
SLURM_JOB_NAME Same as -J, --job-name except within an existing allocation, in which case it is
ignored to avoid using the batch job's name as the name of each job step.
SLURM_JOB_NUM_NODES Same as -N, --nodes. Total number of nodes in the job’s resource allocation.
SLURM_KILL_BAD_EXIT Same as -K, --kill-on-bad-exit. Must be set to 0 or 1 to disable or enable the
option.
SLURM_LABELIO Same as -l, --label
SLURM_MEM_BIND Same as --mem-bind
SLURM_MEM_PER_CPU Same as --mem-per-cpu
SLURM_MEM_PER_GPU Same as --mem-per-gpu
SLURM_MEM_PER_NODE Same as --mem
SLURM_MPI_TYPE Same as --mpi
SLURM_NETWORK Same as --network
SLURM_NNODES Same as -N, --nodes. Total number of nodes in the job’s resource allocation. See
SLURM_JOB_NUM_NODES. Included for backwards compatibility.
SLURM_NO_KILL Same as -k, --no-kill
SLURM_NPROCS Same as -n, --ntasks. See SLURM_NTASKS. Included for backwards compatibility.
SLURM_NTASKS Same as -n, --ntasks
SLURM_NTASKS_PER_CORE Same as --ntasks-per-core
SLURM_NTASKS_PER_GPU Same as --ntasks-per-gpu
SLURM_NTASKS_PER_NODE Same as --ntasks-per-node
SLURM_NTASKS_PER_SOCKET
Same as --ntasks-per-socket
SLURM_OPEN_MODE Same as --open-mode
SLURM_OVERCOMMIT Same as -O, --overcommit
SLURM_OVERLAP Same as --overlap
SLURM_PARTITION Same as -p, --partition
SLURM_PMI_KVS_NO_DUP_KEYS
If set, then PMI key-pairs will contain no duplicate keys. MPI can use this
variable to inform the PMI library that it will not use duplicate keys so PMI can
skip the check for duplicate keys. This is the case for MPICH2 and reduces
overhead in testing for duplicates for improved performance
SLURM_POWER Same as --power
SLURM_PROFILE Same as --profile
SLURM_PROLOG Same as --prolog
SLURM_QOS Same as --qos
SLURM_REMOTE_CWD Same as -D, --chdir=
SLURM_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
SLURM_RESERVATION Same as --reservation
SLURM_RESV_PORTS Same as --resv-ports
SLURM_SEND_LIBS Same as --send-libs
SLURM_SIGNAL Same as --signal
SLURM_SPREAD_JOB Same as --spread-job
SLURM_SRUN_REDUCE_TASK_EXIT_MSG
if set and non-zero, successive task exit messages with the same exit code will be
printed only once.
SLURM_STDERRMODE Same as -e, --error
SLURM_STDINMODE Same as -i, --input
SLURM_STDOUTMODE Same as -o, --output
SLURM_STEP_GRES Same as --gres (only applies to job steps, not to job allocations). Also see
SLURM_GRES
SLURM_STEP_KILLED_MSG_NODE_ID=ID
If set, only the specified node will log when the job or step are killed by a
signal.
SLURM_TASK_EPILOG Same as --task-epilog
SLURM_TASK_PROLOG Same as --task-prolog
SLURM_TEST_EXEC If defined, srun will verify existence of the executable program along with user
execute permission on the node where srun was called before attempting to launch it
on nodes in the step.
SLURM_THREAD_SPEC Same as --thread-spec
SLURM_THREADS Same as -T, --threads
SLURM_THREADS_PER_CORE
Same as --threads-per-core
SLURM_TIMELIMIT Same as -t, --time
SLURM_UNBUFFEREDIO Same as -u, --unbuffered
SLURM_USE_MIN_NODES Same as --use-min-nodes
SLURM_WAIT Same as -W, --wait
SLURM_WAIT4SWITCH Max time waiting for requested switches. See --switches
SLURM_WCKEY Same as -W, --wckey
SLURM_WORKING_DIR -D, --chdir
SLURMD_DEBUG Same as -d, --slurmd-debug. Must be set to 0 or 1 to disable or enable the option.
SRUN_CONTAINER Same as --container.
SRUN_EXPORT_ENV Same as --export, and will override any setting for SLURM_EXPORT_ENV.
OUTPUT ENVIRONMENT VARIABLES
srun will set some environment variables in the environment of the executing tasks on the remote compute
nodes. These environment variables are:
SLURM_*_HET_GROUP_# For a heterogeneous job allocation, the environment variables are set separately
for each component.
SLURM_CLUSTER_NAME Name of the cluster on which the job is executing.
SLURM_CPU_BIND_LIST --cpu-bind map or mask list (list of Slurm CPU IDs or masks for this node, CPU_ID =
Board_ID x threads_per_board + Socket_ID x threads_per_socket + Core_ID x
threads_per_core + Thread_ID).
SLURM_CPU_BIND_TYPE --cpu-bind type (none,rank,map_cpu:,mask_cpu:).
SLURM_CPU_BIND_VERBOSE
--cpu-bind verbosity (quiet,verbose).
SLURM_CPU_FREQ_REQ Contains the value requested for cpu frequency on the srun command as a numerical
frequency in kilohertz, or a coded value for a request of low, medium,highm1 or
high for the frequency. See the description of the --cpu-freq option or the
SLURM_CPU_FREQ_REQ input environment variable.
SLURM_CPUS_ON_NODE Number of CPUs available to the step on this node. NOTE: The select/linear plugin
allocates entire nodes to jobs, so the value indicates the total count of CPUs on
the node. For the select/cons_res and cons/tres plugins, this number indicates the
number of CPUs on this node allocated to the step.
SLURM_CPUS_PER_TASK Number of cpus requested per task. Only set if the --cpus-per-task option is
specified.
SLURM_DISTRIBUTION Distribution type for the allocated jobs. Set the distribution with -m,
--distribution.
SLURM_GPUS_ON_NODE Number of GPUs available to the step on this node.
SLURM_GTIDS Global task IDs running on this node. Zero origin and comma separated. It is read
internally by pmi if Slurm was built with pmi support. Leaving the variable set may
cause problems when using external packages from within the job (Abaqus and Ansys
have been known to have problems when it is set - consult the appropriate
documentation for 3rd party software).
SLURM_HET_SIZE Set to count of components in heterogeneous job.
SLURM_JOB_ACCOUNT Account name associated of the job allocation.
SLURM_JOB_CPUS_PER_NODE
Count of CPUs available to the job on the nodes in the allocation, using the format
CPU_count[(xnumber_of_nodes)][,CPU_count [(xnumber_of_nodes)] ...]. For example:
SLURM_JOB_CPUS_PER_NODE='72(x2),36' indicates that on the first and second nodes
(as listed by SLURM_JOB_NODELIST) the allocation has 72 CPUs, while the third node
has 36 CPUs. NOTE: The select/linear plugin allocates entire nodes to jobs, so the
value indicates the total count of CPUs on allocated nodes. The select/cons_res and
select/cons_tres plugins allocate individual CPUs to jobs, so this number indicates
the number of CPUs allocated to the job.
SLURM_JOB_DEPENDENCY Set to value of the --dependency option.
SLURM_JOB_ID Job id of the executing job.
SLURM_JOB_NAME Set to the value of the --job-name option or the command name when srun is used to
create a new job allocation. Not set when srun is used only to create a job step
(i.e. within an existing job allocation).
SLURM_JOB_NODELIST List of nodes allocated to the job.
SLURM_JOB_NODES Total number of nodes in the job's resource allocation.
SLURM_JOB_PARTITION Name of the partition in which the job is running.
SLURM_JOB_QOS Quality Of Service (QOS) of the job allocation.
SLURM_JOB_RESERVATION Advanced reservation containing the job allocation, if any.
SLURM_JOBID Job id of the executing job. See SLURM_JOB_ID. Included for backwards
compatibility.
SLURM_LAUNCH_NODE_IPADDR
IP address of the node from which the task launch was initiated (where the srun
command ran from).
SLURM_LOCALID Node local task ID for the process within a job.
SLURM_MEM_BIND_LIST --mem-bind map or mask list (<list of IDs or masks for this node>).
SLURM_MEM_BIND_PREFER --mem-bind prefer (prefer).
SLURM_MEM_BIND_SORT Sort free cache pages (run zonesort on Intel KNL nodes).
SLURM_MEM_BIND_TYPE --mem-bind type (none,rank,map_mem:,mask_mem:).
SLURM_MEM_BIND_VERBOSE
--mem-bind verbosity (quiet,verbose).
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_NODEID The relative node ID of the current node.
SLURM_NPROCS Total number of processes in the current job or job step. See SLURM_NTASKS.
Included for backwards compatibility.
SLURM_NTASKS Total number of processes in the current job or job step.
SLURM_OVERCOMMIT Set to 1 if --overcommit was specified.
SLURM_PRIO_PROCESS The scheduling priority (nice value) at the time of job submission. This value is
propagated to the spawned processes.
SLURM_PROCID The MPI rank (or relative process ID) of the current process.
SLURM_SRUN_COMM_HOST IP address of srun communication host.
SLURM_SRUN_COMM_PORT srun communication port.
SLURM_CONTAINER OCI Bundle for job. Only set if --container is specified.
SLURM_STEP_ID The step ID of the current job.
SLURM_STEP_LAUNCHER_PORT
Step launcher port.
SLURM_STEP_NODELIST List of nodes allocated to the step.
SLURM_STEP_NUM_NODES Number of nodes allocated to the step.
SLURM_STEP_NUM_TASKS Number of processes in the job step or whole heterogeneous job step.
SLURM_STEP_TASKS_PER_NODE
Number of processes per node within the step.
SLURM_STEPID The step ID of the current job. See SLURM_STEP_ID. Included for backwards
compatibility.
SLURM_SUBMIT_DIR The directory from which the allocation was invoked from.
SLURM_SUBMIT_HOST The hostname of the computer from which the allocation was invoked from.
SLURM_TASK_PID The process ID of the task being started.
SLURM_TASKS_PER_NODE Number of tasks to be initiated on each node. Values are comma separated and in the
same order as SLURM_JOB_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 two tasks and the fourth node will execute one task.
SLURM_TOPOLOGY_ADDR This is set only if the system has the topology/tree plugin configured. The value
will be set to the names network switches which may be involved in the job's
communications from the system's top level switch down to the leaf switch and
ending with node name. A period is used to separate each hardware component name.
SLURM_TOPOLOGY_ADDR_PATTERN
This is set only if the system has the topology/tree plugin configured. The value
will be set component types listed in SLURM_TOPOLOGY_ADDR. Each component will be
identified as either "switch" or "node". A period is used to separate each
hardware component type.
SLURM_UMASK The umask in effect when the job was submitted.
SLURMD_NODENAME Name of the node running the task. In the case of a parallel job executing on
multiple compute nodes, the various tasks will have this environment variable set
to different values on each compute node.
SRUN_DEBUG Set to the logging level of the srun command. Default value is 3 (info level).
The value is incremented or decremented based upon the --verbose and --quiet
options.
SIGNALS AND ESCAPE SEQUENCES
Signals sent to the srun command are automatically forwarded to the tasks it is controlling with a few
exceptions. The escape sequence <control-c> will report the state of all tasks associated with the srun
command. If <control-c> is entered twice within one second, then the associated SIGINT signal will be
sent to all tasks and a termination sequence will be entered sending SIGCONT, SIGTERM, and SIGKILL to all
spawned tasks. If a third <control-c> is received, the srun program will be terminated without waiting
for remote tasks to exit or their I/O to complete.
The escape sequence <control-z> is presently ignored.
MPI SUPPORT
MPI use depends upon the type of MPI being used. There are three fundamentally different modes of
operation used by these various MPI implementations.
1. Slurm directly launches the tasks and performs initialization of communications through the PMI2 or
PMIx APIs. For example: "srun -n16 a.out".
2. Slurm creates a resource allocation for the job and then mpirun launches tasks using Slurm's
infrastructure (OpenMPI).
3. Slurm creates a resource allocation for the job and then mpirun launches tasks using some mechanism
other than Slurm, such as SSH or RSH. These tasks are initiated outside of Slurm's monitoring or
control. Slurm's epilog should be configured to purge these tasks when the job's allocation is
relinquished, or the use of pam_slurm_adopt is highly recommended.
See https://slurm.schedmd.com/mpi_guide.html for more information on use of these various MPI
implementations with Slurm.
MULTIPLE PROGRAM CONFIGURATION
Comments in the configuration file must have a "#" in column one. The configuration file contains the
following fields separated by white space:
Task rank
One or more task ranks to use this configuration. Multiple values may be comma separated. Ranges
may be indicated with two numbers separated with a '-' with the smaller number first (e.g. "0-4"
and not "4-0"). To indicate all tasks not otherwise specified, specify a rank of '*' as the last
line of the file. If an attempt is made to initiate a task for which no executable program is
defined, the following error message will be produced "No executable program specified for this
task".
Executable
The name of the program to execute. May be fully qualified pathname if desired.
Arguments
Program arguments. The expression "%t" will be replaced with the task's number. The expression
"%o" will be replaced with the task's offset within this range (e.g. a configured task rank value
of "1-5" would have offset values of "0-4"). Single quotes may be used to avoid having the
enclosed values interpreted. This field is optional. Any arguments for the program entered on
the command line will be added to the arguments specified in the configuration file.
For example:
$ cat silly.conf
###################################################################
# srun multiple program configuration file
#
# srun -n8 -l --multi-prog silly.conf
###################################################################
4-6 hostname
1,7 echo task:%t
0,2-3 echo offset:%o
$ srun -n8 -l --multi-prog silly.conf
0: offset:0
1: task:1
2: offset:1
3: offset:2
4: linux15.llnl.gov
5: linux16.llnl.gov
6: linux17.llnl.gov
7: task:7
EXAMPLES
This simple example demonstrates the execution of the command hostname in eight tasks. At least eight
processors will be allocated to the job (the same as the task count) on however many nodes are required
to satisfy the request. The output of each task will be proceeded with its task number. (The machine
"dev" in the example below has a total of two CPUs per node)
$ srun -n8 -l hostname
0: dev0
1: dev0
2: dev1
3: dev1
4: dev2
5: dev2
6: dev3
7: dev3
The srun -r option is used within a job script to run two job steps on disjoint nodes in the following
example. The script is run using allocate mode instead of as a batch job in this case.
$ cat test.sh
#!/bin/sh
echo $SLURM_JOB_NODELIST
srun -lN2 -r2 hostname
srun -lN2 hostname
$ salloc -N4 test.sh
dev[7-10]
0: dev9
1: dev10
0: dev7
1: dev8
The following script runs two job steps in parallel within an allocated set of nodes.
$ cat test.sh
#!/bin/bash
srun -lN2 -n4 -r 2 sleep 60 &
srun -lN2 -r 0 sleep 60 &
sleep 1
squeue
squeue -s
wait
$ salloc -N4 test.sh
JOBID PARTITION NAME USER ST TIME NODES NODELIST
65641 batch test.sh grondo R 0:01 4 dev[7-10]
STEPID PARTITION USER TIME NODELIST
65641.0 batch grondo 0:01 dev[7-8]
65641.1 batch grondo 0:01 dev[9-10]
This example demonstrates how one executes a simple MPI job. We use srun to build a list of machines
(nodes) to be used by mpirun in its required format. A sample command line and the script to be executed
follow.
$ cat test.sh
#!/bin/sh
MACHINEFILE="nodes.$SLURM_JOB_ID"
# Generate Machinefile for mpi such that hosts are in the same
# order as if run via srun
#
srun -l /bin/hostname | sort -n | awk '{print $2}' > $MACHINEFILE
# Run using generated Machine file:
mpirun -np $SLURM_NTASKS -machinefile $MACHINEFILE mpi-app
rm $MACHINEFILE
$ salloc -N2 -n4 test.sh
This simple example demonstrates the execution of different jobs on different nodes in the same srun.
You can do this for any number of nodes or any number of jobs. The executables are placed on the nodes
sited by the SLURM_NODEID env var. Starting at 0 and going to the number specified on the srun command
line.
$ cat test.sh
case $SLURM_NODEID in
0) echo "I am running on "
hostname ;;
1) hostname
echo "is where I am running" ;;
esac
$ srun -N2 test.sh
dev0
is where I am running
I am running on
dev1
This example demonstrates use of multi-core options to control layout of tasks. We request that four
sockets per node and two cores per socket be dedicated to the job.
$ srun -N2 -B 4-4:2-2 a.out
This example shows a script in which Slurm is used to provide resource management for a job by executing
the various job steps as processors become available for their dedicated use.
$ cat my.script
#!/bin/bash
srun -n4 prog1 &
srun -n3 prog2 &
srun -n1 prog3 &
srun -n1 prog4 &
wait
This example shows how to launch an application called "server" with one task, 8 CPUs and 16 GB of memory
(2 GB per CPU) plus another application called "client" with 16 tasks, 1 CPU per task (the default) and 1
GB of memory per task.
$ srun -n1 -c16 --mem-per-cpu=1gb server : -n16 --mem-per-cpu=1gb client
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) 2010-2021 SchedMD LLC.
This file is part of Slurm, a resource management program. For details, see
<https://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.
SEE ALSO
salloc(1), sattach(1), sbatch(1), sbcast(1), scancel(1), scontrol(1), squeue(1), slurm.conf(5),
sched_setaffinity (2), numa (3) getrlimit (2)
December 2021 Slurm Commands srun(1)