How to get parallel to use multiple instances by using degree option. Let’s assume that I have a 2 node rac database.
Option 1 - If you don’t specify a degree it does it , but it creates 2 * cpu_count sessions * parallel_threads_per_cpu on each instance – which may be an overkill
Option 2 - If you use a degree it seems to just go to one instance only.
Option 3 – This should open up 8 sessions on both nodes both does not.
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Select /*+ PARALLEL */ -
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Select /*+ PARALLEL(4) */ - Only goes to one session
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Select /*+ PARALLEL(4,2) */ - Doesn’t seem to work the way I expected it