Oracle® Database Reference 10g Release 2 (10.2) Part Number B14237-02 |
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Property | Description |
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Parameter type | Integer |
Default value | Operating system-dependent |
Modifiable | No |
Range of values | 2148 to 65535 (64 KB - 1) |
Real Application Clusters | Multiple instances must have the same value. |
PARALLEL_EXECUTION_MESSAGE_SIZE
specifies the size of messages for parallel execution (formerly referred to as parallel query, PDML, Parallel Recovery, replication).
On most platforms, the default value is 2148
bytes if PARALLEL_AUTOMATIC_TUNING
is set to false
, and 4096
bytes if PARALLEL_AUTOMATIC_TUNING
is set to true
. 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.
Note:
WhenPARALLEL_AUTOMATIC_TUNING
is set to TRUE
, message buffers are allocated out of the large pool. In this case, the default is generally higher. Note that the PARALLEL_AUTOMATIC_TUNING
parameter has been deprecated.