PARALLEL_MIN_PERCENT

PARALLEL_MIN_PERCENT lets you specify the minimum percentage of the requested number of parallel execution processes required for parallel execution.

Property Description
Parameter type Integer
Default value 0
Modifiable ALTER SESSION
Modifiable in a PDB No
Range of values 0 to 100
Basic No
Oracle RAC Multiple instances can have different values.

This parameter controls the behavior for parallel operations when parallel statement queuing is not enabled (when PARALLEL_DEGREE_POLICY is set to manual or limited). It ensures that an operation always gets a minimum percentage of parallel execution servers or errors out. Setting this parameter ensures that parallel operations will not execute unless adequate resources are available. The default value of 0 means that no minimum percentage of processes has been set.

Consider the following settings:

PARALLEL_MIN_PERCENT = 50
PARALLEL_MIN_SERVERS = 5
PARALLEL_MAX_SERVERS = 10

If 8 of the 10 parallel execution processes are busy, only 2 processes are available. If you then request a query with a degree of parallelism of 8, the minimum 50% will not be met.

You can use this parameter with PARALLEL_ADAPTIVE_MULTI_USER. In a multi-user environment, an individual user or application can set PARALLEL_MIN_PERCENT to a minimum value until sufficient resources are available on the system and an acceptable degree of parallelism is returned.

See Also: