PBS

PBS

PBS (Portable Batch System) is a workload management and job scheduling system commonly used in high-performance computing environments. It helps allocate cluster resources and manage job execution efficiently.

How does it work?

PBS organizes and manages tasks in a cluster by scheduling jobs, allocating resources, and ensuring optimal usage. It provides a robust environment for handling both simple and complex workflows.

Key Concepts

Job submission: Users submit jobs specifying resource requirements and runtime limits.

Queue: Jobs are queued and prioritized based on resource needs, job policies, and user configurations.

Resource allocation: PBS allocates resources to queued jobs based on availability and priority.

Job execution: PBS runs jobs on the allocated resources and tracks their progress.

Submitting Jobs

To submit a job to PBS, create a script with the required job details and submit it using the qsub command.

qsub myscript.pbs  

Example PBS Script

#!/bin/bash  

#PBS -N myjob          # Job name  

#PBS -q compute        # Queue name  

#PBS -l nodes=1:ppn=4  # Number of nodes and processors per node  

#PBS -l walltime=01:00:00 # Maximum runtime  

#PBS -j oe             # Combine standard output and error  

#PBS -d .              # Start job in current working directory  

# Commands to execute:  

echo "Hello, PBS!"  

Key Options

-N: Sets the job name.

-q: Specifies the queue to submit the job.

-l nodes=1:ppn=4: Requests 1 node with 4 processors per node.

-l walltime: Specifies the maximum runtime.

-j oe: Combines standard output and error into one file.

-d: Runs the job in the current working directory.

Managing Jobs

Checking job status: Use qstat to view job status and queue information.

qstat

Cancelling jobs: Cancel a job with 

qdel job_id

Job details: 

qstat -f job_id