Page Comparison

...

• Python constant: pbs.EXECJOB_PRERESUME
• Event Parameters: 
  • pbs.event().job - This is a pbs.job object representing the job that will be resumed. This job object cannot be modified under this hook.
  • pbs.event().vnode_list[] - This is a dictionary of pbs.vnode objects, keyed by vnode name, listing the vnodes that are assigned to the job. The vnode objects in the vnode_list cannot be modified.
• Hook Attributes:
  • fail_action: This hook will not allow a fail action to be set.
  • user: This hook will only allow the value "pbsadmin".
• Details:
  • An execjob_preresume hook is executed by the primary mom when a request to resume the job is received.

  • An execjob_preresume hook is executed by the sister mom when a request from the primary mom to resume the job's tasks is received.

  • A call to pbs.event().accept() means the hook code has executed cleanly.

  • A call to pbs.event().reject() means the hook code was not able to fully accomplish its task

    • Note: this will prevent all MoMs from resuming jobs.
    • Keeping with hook design, if one execjob_preresume hook is rejected, the other execjob_preresume hooks with a higher order value will not run.

  • If the execjob_postsuspend preresume hook script encounters an unexpected error causing an unhandled exception, or times out due to the hook's alarm setting, the hook will act similar to a pbs.event().reject().

    • Note: this will prevent all MoMs from resuming jobs.
• Internal Design:
  
  • The MS will complete the event first. If it is not rejected, the sisters will then run their hooks.
  • All moms must accept the event before the job can be resumed.
• Consumer:
  • Hooks like cgroups that need to take action when resource allocation changes.
    • Because the cgroups are cleaned up on suspension, it has to be recreated/modified when the job is resumed. Otherwise, the job will not have the resources it requested.
• Caveats
  • Current behavior shows that when a PBS_BATCH_SignalJob to resume a job is rejected by the mom, the server starts another scheduling cycle. If the scheduler says it can still be resumed, it will try again. If the execjob_preresume hook always rejects, there is nothing preventing this loop. Again, this is consistent with current behavior, but now it's easier to enter this loop.

...