Jenkins runs "branch indexing" jobs to trigger multi-branch pipeline jobs automatically; for instance a webhook connected to source control will cause a branch indexing job to scan for newly created branches to create new corresponding branch-specific jobs, trigger branch-specific jobs which have new commits, and delete branch-specific jobs where the corresponding branch no longer exists. These jobs always run on the controller (master) node and seem to always run in series, which means if you have many jobs then you will end up with a long backlog of branch indexing jobs.
These jobs do not behave like normal Jenkins jobs - they don't run on the executors that have been defined on the controller, which means even if you have no jobs running and several executors sitting idle the branch indexing jobs will still run one at a time.
Is there any way to force these branch indexing jobs to run concurrently?
