Is the grinder doing more work than required?

[pshipton]

Describe the bug
I started a grinder using "NodesByIterations" on 5 machines. The parent job loads all the repos and downloads the JVM, only to create 5 child jobs that actually runs the testing. It seems loading the repos and downloading the JVM in the parent job is a waste of time.
https://openj9-jenkins.osuosl.org/job/Grinder/1292/console

To Reproduce
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Expected behavior
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[llxia]

I agree. We only need to download JVM to run TKG when PARALLEL=Dynamic. In other parallel cases (i.e., NodesByIterations, Subdir), we do not need to download JVM and clone test repos.

[llxia]

As @AdamBrousseau pointed out, there is another corner case where PARALLEL=Dynamic and NUM_MACHINES > 1, but the available machine is only 1. In this case, we should run it serially (not launching the child job).