Most jobs do not belong to an exclusion set. These are typically the feature support jobs, as previously described, and they can co-exist and contend with any of the other jobs.
These jobs include:
Exclusion sets do not change the scope of the individual jobs themselves, so any runtime improvements from parallelism are the result of job management and impact control. The Job Engine monitors node CPU load and drive I/O activity per worker thread every 20 seconds to ensure that maintenance jobs do not cause cluster performance problems.