Add job preemption details to Summit User Guide

[jack-morrison]

No description provided.

[chrisfuson]

Must use the killable queue. Bins 4 and 5 eligible for pre-emption (by jobs in bins 1 and 2) once the bin's standard max walltime limit has been reached. Max walltime for killable queue is 24 hours. For example, in the killable queue a job in bin5 can request a walltime of 24 hours. It will be eligible for pre-emption from a job in bin1 or bin2 after 2-hours of runtime.

Killable queue jobs requesting fewer than 91 nodes will be rejected at submission time by the submit filter.

[jack-morrison]

Killable queue jobs requesting fewer than 91 nodes will be rejected at submission time by the submit filter.

@chrisfuson why would we want to exclude bin5 jobs from being preempt-able?
This doesn't seem to be in place:

summit login5$ bsub -q killable -W 10 -J test -nnodes 1 -PSTF007 -Is $SHELL
Job <649324> is submitted to queue <killable>.
<<Waiting for dispatch ...>>
<<Starting on batch4>>

[chrisfuson]

@jack-morrison node requests below 91 are eligible. This should be bins 4 and 5.

`summit-login5 237> bsub -q killable -W 10 -J test -nnodes 92 -PSTF007 -Is $SHELL

Batch job not submitted. Please address the following and resubmit:

** Requested nodes (92) over limit. Please resubmit with a node count below 91.

---

Please contact help@olcf.ornl.gov if you need assistance.

Request aborted by esub. Job not submitted.
summit-login5 238>`

[jack-morrison]

Ah, over 91 nodes is what we're going for here. Got it 👍