Grab environment variables needed for grid engine

[jekriske-lilly]

When running as a service, the path for qsub/qstat/qdel commands is needed in the environment. In addition, several SGE environment variables are needed in order to submit jobs to the cluster. These are mentioned in the SGE install guides and are carried over to Univa Grid Engine as well.

Here's an older admin guide (page 7) describing the variables

Tested with UGE-8.6.4

[rkdarst]

Does anyone know how the GridengineSpawner could work without this? Does everyone else just manually specify additional keepenv, or could there be some other local differences here? While I don't see anything wrong here, I'm curious about the big picture to ensure we don't break things for other people.

Are you interested in being a grid engine maintainer?

[jekriske-lilly]

I'm not sure how others are doing this unless they are doing something custom to set those env variables within the service and use keepvars. Without these, they should be greeted with the super helpful error from qsub:

Unable to initialize environment because of error: error without diagnosis message
Exiting.

I don't mind helping to maintain the grid engine piece. We have 1000+ users on our cluster, keeping this working properly is super important.

@cbjhnsn you mentioned your group is using SGE. Would you foresee any issues in your environment with the approach in this PR?

[mbmilligan]

This seems well contained to the GridEngineSpawner. Not seeing any dissenting opinions, accepting.

[welcome]

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