PARALLEL_EXECUTION_MESSAGE_SIZE
PARALLEL_EXECUTION_MESSAGE_SIZE specifies the size of messages used for parallel execution (formerly referred to as parallel query, PDML, Parallel Recovery, replication).
| Property | Description |
|---|---|
| Parameter type | Integer |
| Default value | Operating system-dependent |
| Modifiable | No |
| Modifiable in a PDB | No |
| Range of values | Minimum: 2148 Maximum: 65536, but some operating systems may have a smaller value |
| Basic | No |
| Oracle RAC | Multiple instances must have the same value. |
On most platforms, the default value is as follows:
-
16384bytes ifCOMPATIBLEis set to11.2.0or higher -
2148bytes ifCOMPATIBLEis less than11.2.0
The default value is adequate for most applications. Larger values require a larger shared pool. Larger values result in better performance at the cost of higher memory use. For this reason, replication gets no benefit from increasing the size.
See Also: Oracle AI Database VLDB and Partitioning Guide to learn how this parameter affects memory consumption for parallel operations, including parallel execution