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... I am trying to identify if it is possible to use parallel statement queueing without using auto DOP. My current environment does not use auto DOP
and I was looking to use queueing to solve a performance variance issue I am seeing.
I don't fully understand your question or requirements, but have you considered using the "PARALLEL" hint?
There is a feature in 11g where you can place parallel statements in a queue if there are not sufficient parallel servers available. The statements are then run once sufficent parallel servers are available. I am looking to use this if possible to prevent downgraded statements from being run when there are not sufficient parallel servers. I would rather wait and use full parallelism then be downgraded and have a longer statement run time.
According to Oracle documentation advanced features of parallel execution such as automatic DOP, statement queuing and in-memory parallel execution depend on the value of PARALLEL_DEGREE_POLICY parameter. Statement queuing is only available if the parameter set to AUTO.
Here is the [url http://docs.oracle.com/cd/E11882_01/server.112/e25523/parallel002.htm#CIHEFJGC]document.
Since automatic DOP itself depends on many other factors to work (such as DEFAULT degree set for the objects) it's theoretically possible to use queuing and still explicitly specify DOP for majority of the objects through either hints of parallel degree property.
Hope it helps.