RE: CPU usage overhead after setting Max DOP

SSC Guru

Points: 323504

August 30, 2017 at 7:59 am

#1957436

I think you should have fixed the one query that was the issue, since you already identified it as a problem.
instead you changed the entire server behavior to account for one bad query.

In my shop, we already have a maxdop set to 8 instead of the default of zero, because I'm under the impression that the combining of those more-than-8-parallel streams can often cost more to merge them together than a lower number of streams, so in general, i think 8 is a sweet spot.

what is double CPU for you? from 25 to 50 percent, or from 2 percent 4 percent?
i think details are going to be important here

Lowell

--help us help you! If you post a question, make sure you include a CREATE TABLE... statement and INSERT INTO... statement into that table to give the volunteers here representative data. with your description of the problem, we can provide a tested, verifiable solution to your question! asking the question the right way gets you a tested answer the fastest way possible!