Re: Optimal degree of parallelism

I believe that this myth exists because one CPU will be the "master" and the rest are the "slaves". Therefore, the "optimal" degree is n-1 where n=number of CPUs. But this myth is pure hogwash. And Oracle's default degree is *usually* 2*n=PARALLEL_THREADS_PER_CPU*CPU_COUNT.

In the end, the "optimal" degree is the one that gets your query to run faster. And this is done query by query, not instance-wide.

Cheers,
Brian

-- 
===================================================================

Brian Peasland
dba_at_remove_spam.peasland.com

Remove the "remove_spam." from the email address to email me.


"I can give it to you cheap, quick, and good. Now pick two out of
 the three"