1.251 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 |
|
Modifiable |
|
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:
-
Oracle Database SQL Tuning Guide for more information about parallel execution
-
"PARALLEL_DEGREE_POLICY", "PARALLEL_MAX_SERVERS", "PARALLEL_MIN_SERVERS", and "PARALLEL_ADAPTIVE_MULTI_USER"