When a job should be set as critical
You should always set a job as critical if its delay could imply a delay in the plan. WLM knows the availability of the overall resources against the system workloads when the current plan is executed and the real duration of a job is determined by this factor. Therefore, it is better also that you set as critical those jobs that would be on a critical path if their estimated durations were only minimally longer than at present. To set a job as critical, set the appropriate value in the CRITICAL field of the JOB, WTO, AND PRINT OPTIONS panel, which is accessible from either the APPLICATION DESCRIPTION panel or the MODIFYING THE CURRENT PLAN panel (for detailed information, see Specifying options for automation).