PARALLEL_MAX_SERVERS <=> CPU_COUNT x PARALLEL_THREADS_PER_CPU x 2x 5 <=>Specifies the maximum number of parallel execution processes and parallel recovery processes for an instance.
PARALLEL_EXECUTION_MESSAGE_SIZE <=> 2 KB (port specific) <=> Increase to 4k or 8k to improve parallel execution performance if sufficient SGA memory exists.
PARALLEL_ADAPTIVE_MULTI_USER <=> TRUE <=> Causes parallel execution SQL to throttle DOP requests to prevent system overload.
The following example shows a statement that sets the DOP to 4 on a table:
ALTER TABLE orders PARALLEL 4;
This next example sets the DOP on an index to 4:
ALTER INDEX iorders PARALLEL 4;
This last example sets a hint to 4 on a query:
SELECT /*+ PARALLEL(orders, 4) */ COUNT(*) FROM orders;
The initialization parameter PARALLEL_MIN_PERCENT specifies the desired minimum percentage of requested parallel execution servers. This parameter affects DML and DDL operations as well as queries
PARALLEL_EXECUTION_MESSAGE_SIZE <=> 2 KB (port specific) <=> Increase to 4k or 8k to improve parallel execution performance if sufficient SGA memory exists.
PARALLEL_ADAPTIVE_MULTI_USER <=> TRUE <=> Causes parallel execution SQL to throttle DOP requests to prevent system overload.
The following example shows a statement that sets the DOP to 4 on a table:
ALTER TABLE orders PARALLEL 4;
This next example sets the DOP on an index to 4:
ALTER INDEX iorders PARALLEL 4;
This last example sets a hint to 4 on a query:
SELECT /*+ PARALLEL(orders, 4) */ COUNT(*) FROM orders;
The initialization parameter PARALLEL_MIN_PERCENT specifies the desired minimum percentage of requested parallel execution servers. This parameter affects DML and DDL operations as well as queries
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