| Property | Description |
|---|---|
|
Parameter type |
Integer |
|
Default value |
Operating system-dependent, usually |
|
Modifiable |
|
|
Range of values |
Any nonzero number |
|
Basic |
No |
Note:
This parameter applies to parallel execution in exclusive mode as well as in a Real Application Clusters environment.
PARALLEL_THREADS_PER_CPU specifies the default degree of parallelism for the instance and determines the parallel adaptive and load balancing algorithms. The parameter describes the number of parallel execution processes or threads that a CPU can handle during parallel execution.
The default is platform-dependent and is usually adequate. You should decrease the value of this parameter if the system appears to be overloaded when a representative parallel query is executed. You should increase the value if the system is I/O bound.
See Also:
Oracle Database SQL Tuning Guide for more information about parallel execution
Oracle Database VLDB and Partitioning Guide for information about how the optimizer automatically determines the degree of parallelism for a statement