NAME

       Slurm::Stepctx - Step launching functions in libslurm

SYNOPSIS

        use Slurm;

        $slurm = Slurm::new();
        $params = {job_id => 1234, ...};
        $ctx = $slurm->step_ctx_create($params);
        $rc = $ctx->launch({...}, {task_start => sub {...},
                                task_finish => sub {...} });

DESCRIPTION

       The Slurm::Stepctx class is a wrapper of the job step context and step launching functions
       in libslurm. This package is loaded and bootstraped with package Slurm.

METHODS

   STEP CONTEXT CREATION FUNCTIONS
       Please see "SLURM TASK SPAWNING FUNCTIONS" in Slurm for step context creation functions.

   STEP CONTEXT MANIPULATION FUNCTIONS
       $rc = $ctx->get($ctx_key, ...);

       Get parameters from a job step context.

       • INPUT $ctx_key: type of the parameter to get. Supported key and the corresponding result
         data are:

         • $rc = $ctx->get(SLURM_STEP_CTX_STEPID, $stepid);

           Get the created job step id. $stepid will be set to the step id number.

         • $rc = $ctx->get(SLURM_STEP_CTX_TASKS, $tasks);

           Get array of task count on each node. $tasks will be set to an array reference.

         • $rc = $ctx->get(SLURM_STEP_CTX_TID, $nodeid, $tids);

           Get array of task IDs for specified node. $nodeid specifies index of the node. $tids
           will be set to an array reference.

         • $rc = $ctx->get(SLURM_STEP_CTX_RESP, $resp);

           TODO: this is not exported. Get job step create response message.

         • $rc = $ctx->get(SLURM_STEP_CTX_CRED, $cred);

           Get credential of the created job step. $cred will be an opaque object blessed to
           "Slurm::slurm_cred_t".

         • $rc = $ctx->get(SLURM_STEP_CTX_SWITCH_JOB, $switch_info);

           Get switch plugin specific info of the step. $switch_info will be an opaque object
           blessed to "Slurm::switch_jobinfo_t".

         • $rc = $ctx->get(SLURM_STEP_CTX_NUM_HOSTS, $num);

           Get number of nodes allocated to the job step.

         • $rc = $ctx->get(SLURM_STEP_CTX_HOST, $nodeid, $nodename);

           Get node name allocated to the job step. $nodeid specifies index of the node.

         • $rc = $ctx->get(SLURM_STEP_CTX_JOBID, $jobid);

           Get job ID of the job step.

         • $rc = $ctx->get(SLURM_STEP_CTX_USER_MANAGED_SOCKETS, $numtasks, $sockets);

           Get user managed I/O sockets. TODO: describe the parameters.

       • RET: error code.

       $rc = $ctx->daemon_per_node_hack();

       Hack the step context to run a single process per node, regardless of the settings
       selected at Slurm::Stepctx::create() time.

       • RET: error code.

   STEP TASK LAUNCHING FUNCTIONS
       $rc = $ctx->launch($params, $callbacks);

       Launch a parallel job step.

       • IN $params: parameters of task launching, with structure of
         "slurm_step_launch_params_t".

       • IN $callbacks: callback functions, with structure of "slurm_step_launch_callbacks_t".
         NOTE: the callback functions will be called in a thread different from the thread
         calling the "launch()" function.

       • RET: error code.

       $rc = $ctx->launch_wait_start();

       Block until all tasks have started.

       • RET: error code.

       $ctx->launch_wait_finish();

       Block until all tasks have finished (or failed to start altogether).

       $ctx->launch_abort();

       Abort an in-progress launch, or terminate the fully launched job step. Can be called from
       a signal handler.

       $ctx->launch_fwd_signal($signo);

       Forward a signal to all those nodes with running tasks.

       • IN $signo: signal number.

SEE ALSO

       Slurm

AUTHOR

       This library is created by Hongjia Cao, <hjcao(AT)nudt.edu.cn> and Danny Auble,
       <da(AT)llnl.gov>. It is distributed with SLURM.

COPYRIGHT AND LICENSE

       This library is free software; you can redistribute it and/or modify it under the same
       terms as Perl itself, either Perl version 5.8.4 or, at your option, any later version of
       Perl 5 you may have available.