Job classes

Job classes specify limits for resource consumption by batch jobs. A job class establishes a policy for resource consumption by a set of batch jobs. Through this policy, execution time, number of concurrent jobs, job log, and job output queue storage can be controlled. This topic lists the limits enforced by job classes.

Job classes can be configured using the administrative console and stored in an .xml file called jobclass.xml under a profile_root/config/cells/cell_name/gridjobclasses/ directory. Each job is assigned to a job class.

A job class establishes policy for:

Execution time

Maximum time a job can run before being automatically canceled by the system.

Concurrent jobs

Maximum number of concurrently dispatched jobs of a given job class.

Job log retention

Specifies the rule for deleting aged job logs. Retention can be specified by either space or time:

Space: Specified in megabytes. Job logs of the specified class are deleted from oldest to newest on an endpoint if the sum of space used by job logs exceeds the specified maximum.
Time: Specified as an integral number of days. Job logs of the specified class older than N days old are automatically deleted by the system.

Job output queue

Specifies the rule for deleting jobs on the job output queue. A job is on the output queue after it has either completed, or stopped, or canceled. Output queue policy allows for automatic purging of the output queue by:

Number: Specified as an integral number of jobs. When jobs on the output queue of the specified class exceed this number, they are deleted oldest to newest until the total is less than the specified number.
Time: Specified as an integral number of days. Job logs of the specified class older than N days old are automatically deleted by the system.

Following are the limits enforced by job classes:

maxExecutionTime: An integer, which specifies the maximum number of seconds a job is allowed to run before it is canceled.
maxConcurrentJob: An integer, which specifies the maximum number of jobs belonging to same job class that can be dispatched to a cell. When this limit is reached, new jobs belonging to the same job class are not dispatched until the ones that are currently running complete execution.
maxClassSpace: An integer that specifies the amount of space, in megabytes, that is allowed for a job log belonging to this job class. When this limit is reached, job logs are deleted oldest to newest.
maxFileAge: An integer, which specifies the number of days a job log of this job class is stored. Job logs older than the number of days are deleted.
maxJob: An integer, which specifies the maximum number of jobs of this class that are allowed on the output queue. When this limit is exceeded, the job is automatically purged, oldest to newest.
maxJobAge: An integer value which specifies the maximum of number of days a job of this class is allowed on the output queue. Jobs older than this value are automatically purged.

Using job classes in your xJCL file

After creating the job class with the administrative console, the job class can be associated with a particular job by adding it to the job element of your xJCL file, using the class attribute.

<job name="SimpleCIEar" class="MyJobClass"...

For parallel job processing, the job-class attribute of the run element can be used to specify the job class to use for sub-jobs. A sub-job does not inherit the job class of the top-level job, and will use the "Default" job class if none is specified.

<run instances="multiple" jvm="multiple" job-class="MyJobClass"...

When no job class is specified, the job or sub job will run under the "Default" job class provided by the product. This job class is configured to limit the maximum number of concurrent dispatched jobs to 25 by default.