Job Class plays an important role in background job processing and helps in scheduling and executing high priority jobs even during peak hours.
Jobs can be classified into three types of job classes based on the priority of the jobs.
The three types of job classes are:
- Class A
- Class B
- Class C
Job Class A is the highest priority job, followed by Job Class B which is followed by Job Class C (lowest and default priority for most jobs). Job classes are very useful and we need to reserve some of the background work processes for scheduling more critical/high priority jobs (Class A jobs). This can ensure that class A jobs will always have free processes so that they can be executed. They can be processed as well by normal background processes.
To schedule jobs with higher priority, users must have batch administrator access. Following authorization is required for this purpose:
Authorization object – S_BTCH_ADM (BTCADMIN = Y)
The advantage of having work processes reserved for class A jobs is that even when there are many released jobs of class C waiting to be processed because all work processes are busy with other jobs , these normal priority jobs will not use the reserved work processes Intended for jobs with the class A. Therefore , even in high load background situations, administrators can release important jobs by assigning a higher priority job class.
What are the advantages of having Class A job? – As we discussed earlier that Class A jobs are the jobs which hold highest priority and we reserve some of the background processes for scheduling high priority jobs. Hence, during the peak hours when there are many released jobs of Class C and all work processes are busy with other jobs, these high priority jobs (Class A Jobs) can use the reserved background work processes for processing their jobs. Therefore, even in high load situations, the administrators can release important jobs by assigning them a higher priority Class.
Points to note:
- We can reserve any number of background work processes for Class A jobs.
- Reserving work processes for class A jobs does not reserve any particular work process in a server for class A jobs, but rather makes sure a certain number of work processes is free at all times. This can be done via tcode RZ04 (Operation Modes). We will discuss more about Operation Modes (RZ04) in our later post.