Follow the PBS Pro Design Document Guidelines.
Setting load_balancing to true will make the scheduler take into account the load average on vnodes. This requires the scheduler to contact the mom via the rm library.
This is a slow way of doing things, as the scheduler will ping each vnode every cycle. Instead, just like mom dynamic resources, it should be set in an exechost hook.
load_balancing will be marked as deprecated in the documentation & eventually removed from the sched config
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