MAX DEGREE field (PARAMDEG subsystem parameter)
The PARAMDEG subsystem parameter specifies the maximum degree of parallelism that is to be allowed for a parallel group. When you specify a value for this parameter, you limit the degree of parallelism so that DB2® cannot create too many parallel tasks that use virtual storage.
Acceptable values: | 0 to 254 |
Default: | 0 |
Update: | option 19 on panel DSNTIPB |
DSNZPxxx: | DSN6SPRM PARAMDEG |
The default value of 0 means that DB2 will choose a maximum degree of parallelism that is based on the system configuration.
When optimization hints for parallelism are used, the value of the PARAMDEG subsystem parameter does not limit the degree of parallelism at bind time. However, the value of the PARAMDEG subsystem parameter is enforced at execution time. So, if the value of the PARAMDEG subsystem parameter is lower than the degree of parallelism that is specified at bind time, then the degree of parallelism is reduced at execution time.