1.150 JOB_QUEUE_PROCESSES

JOB_QUEUE_PROCESSES specifies the maximum number of job slaves per instance that can be created for the execution of DBMS_JOB jobs and Oracle Scheduler (DBMS_SCHEDULER) jobs.

Property	Description
Parameter type	Integer
Default value	`4000`
Modifiable	`ALTER SYSTEM`
Modifiable in a PDB	Yes
Range of values	`0` to `4000`
Basic	No
Oracle RAC	Multiple instances can have different values.

DBMS_JOB and Oracle Scheduler share the same job coordinator and job slaves, and they are both controlled by the JOB_QUEUE_PROCESSES parameter.

If the value of JOB_QUEUE_PROCESSES is set to 0 in a non-CDB or in a CDB root, then DBMS_JOB jobs and Oracle Scheduler jobs will not run in the non-CDB or in the root.

If JOB_QUEUE_PROCESSES is set to a value in the range of 1 to 4000 in a non-CDB or in a CDB root, then DBMS_JOB jobs and Oracle Scheduler jobs will run. The actual number of job slaves created for Oracle Scheduler jobs is auto-tuned by the Scheduler depending on several factors, including available resources, Resource Manager settings, and currently running jobs. However, the combined total number of job slaves running DBMS_JOB jobs and Oracle Scheduler jobs on an instance can never exceed the value of JOB_QUEUE_PROCESSES for that instance.

In a multitenant container database (CDB) environment, JOB_QUEUE_PROCESSES in the CDB root indicates the absolute maximum number of total jobs allowed in the whole instance. JOB_QUEUE_PROCESSES specified in a PDB indicates the maximum of jobs allowed in that PDB.

Oracle Streams Advanced Queuing uses Oracle Scheduler for message propagation. Materialized views use Oracle Scheduler for automatic refreshes. Setting JOB_QUEUE_PROCESS to 0 will disable these features and any other features that use Oracle Scheduler or DBMS_JOB.

Note:

DBMS_JOB is deprecated in Oracle Database 12c Release 2 (12.2.0.1) and may be removed in a future release. Oracle recommends that you use DBMS_SCHEDULER instead.