class lightning.pytorch.plugins.environments.SLURMEnvironment(auto_requeue=True, requeue_signal=None)[source]

Bases: ClusterEnvironment

Cluster environment for training on a cluster managed by SLURM.

You can configure the main_address and main_port properties via the env variables MASTER_ADDR and MASTER_PORT, respectively.

  • auto_requeue (bool) – Whether automatic job resubmission is enabled or not. How and under which conditions a job gets rescheduled gets determined by the owner of this plugin.

  • requeue_signal (Optional[Signals]) – The signal that SLURM will send to indicate that the job should be requeued. Defaults to SIGUSR1 on Unix.

static detect()[source]

Returns True if the current process was launched on a SLURM cluster.

It is possible to use the SLURM scheduler to request resources and then launch processes manually using a different environment. For this, the user can set the job name in SLURM to ‘bash’ or ‘interactive’ (srun –job- name=interactive). This will then avoid the detection of SLURMEnvironment and another environment can be detected automatically.

Return type:



The rank (index) of the currently running process across all nodes and devices.

Return type:



The rank (index) of the currently running process inside of the current node.

Return type:



The rank (index) of the node on which the current process runs.

Return type:


static resolve_root_node_address(nodes)[source]

The node selection format in SLURM supports several formats.

This function selects the first host name from :rtype: str

  • a space-separated list of host names, e.g., ‘host0 host1 host3’ yields ‘host0’ as the root

  • a comma-separated list of host names, e.g., ‘host0,host1,host3’ yields ‘host0’ as the root

  • the range notation with brackets, e.g., ‘host[5-9]’ yields ‘host5’ as the root

validate_settings(num_devices, num_nodes)[source]

Validates settings configured in the script against the environment, and raises an exception if there is an inconsistency.

Return type:



The number of processes across all devices and nodes.

Return type:


property creates_processes_externally: bool

Whether the environment creates the subprocesses or not.

property main_address: str

The main address through which all processes connect and communicate.

property main_port: int

An open and configured port in the main node through which all processes communicate.