That is incorrect but a common misconception (I used to believe the same). Try using it and you'll see the generated code is slower for stores on x86: https://g

That is incorrect but a common misconception (I used to believe the same). Try using it and you'll see the generated code is slower for stores on x86: https://godbolt.org/z/KrzT9bTKf https://godbolt.org/z/KrzT9bTKf I agree with GP - the commonly given "always use sequentially consistent" advice is not really good advice. It should be "use a mutex wherever possible", but once you decide that's not performant enough, you probably often do want acq/rel or relaxed. I've actually found seq_cst to be quite rare.