I have some jobs that can't/shouldn't be run concurrently with any other, e.g. a test where we want to measure the runtime with a large input; or a job that housekeeps all the sandboxes which can cause file locking issues. Heavy job plugin with weight set equal to the number of executors fixed my problem but if the number of executors would go up then other jobs would get in in parallel.

I propose that a special value, like 0 or "max" or "all" can be put in job weight and the heavy job plugin will occupy all executors.