Max Worker Threads

Erik Darling warns against messing with the Max Worker Threads setting:

The thing is, all changing that setting does is help you not run out of worker threads. It doesn’t make queries run any better or faster. In fact, under load, performance will most likely be downgraded to Absolute Rubbish© either way.

What’s worse? Running out of worker threads and queries having to wait for them to free up, or having way more queries trying to run on the same CPUs? Six of one, half dozen of punching yourself squarely in the nose.

I think there are a couple good counter-cases brought up in the comments (around mirroring and Service Broker), but it is solid general advice.

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