>Configuration rarely impacts such trivial cases.

Really? For example buffered vs unbuffered communication won't impact such a case?

One should only assume "thread affinity or page locality" after checking the configuration options (and maybe even later, after profiling).

>In that case since you are waiting for the answer at every iteration, I'm not sure I see how it could have an impact.

In this particular case, yes.

I was making a point against the more generic "configuration rarely impacts such trivial cases" you said, which I've not found to be the general case.

The important part of my comment is such trivial cases ;)

Well, especially the "such", whereas I considered that "trivial cases" is the important one.

Buffering impacts performance when it transforms many small writes into one big write (same for reads). In that case since you are waiting for the answer at every iteration, I'm not sure I see how it could have an impact.