Execution environments

In order to give an impression that an individual QCG-PilotJob task is executed directly by the queuing system a set of environment variables, typically set by the queuing system, is overwritten and passed to the job. These variables give the application all typical information about a job it can be interested in, e.g. the amount of assigned resources. In case of parallel application an appropriate machine file is created with a list of resources for each task. Additionally to unify the execution regardless of the queuing system a set of variables independent from a queuing system is defined and passed to tasks.

Slurm execution environment

For the SLURM scheduling system, an execution environment for a single job contains the following set of variables:

  • SLURM_NNODES - a number of nodes

  • SLURM_NODELIST - a list of nodes separated by the comma

  • SLURM_NPROCS - a number of cores

  • SLURM_NTASKS - see SLURM_NPROCS

  • SLURM_JOB_NODELIST - see SLURM_NODELIST

  • SLURM_JOB_NUM_NODES - see SLURM_NNODES

  • SLURM_STEP_NODELIST - see SLURM_NODELIST

  • SLURM_STEP_NUM_NODES - see SLURM_NNODES

  • SLURM_STEP_NUM_TASKS - see SLURM_NPROCS

  • SLURM_NTASKS_PER_NODE - a number of cores on every node listed in SLURM_NODELIST separated by the comma,

  • SLURM_STEP_TASKS_PER_NODE - see SLURM_NTASKS_PER_NODE

  • SLURM_TASKS_PER_NODE - see SLURM_NTASKS_PER_NODE

QCG Execution environment

To unify the execution environment regardless of the queuing system the following variables are set:

  • QCG_PM_NNODES - a number of nodes

  • QCG_PM_NODELIST- a list of nodes separated by the comma

  • QCG_PM_NPROCS - a number of cores

  • QCG_PM_NTASKS - see QCG_PM_NPROCS

  • QCG_PM_STEP_ID - a unique identifier of a job (generated by QCG-PilotJob Manager)

  • QCG_PM_TASKS_PER_NODE - a number of cores on every node listed in QCG_PM_NODELIST separated by the comma

  • QCG_PM_ZMQ_ADDRESS - an address of the network interface of QCG-PilotJob Manager (if enabled)