doc: clarify synchronous blocking of worker stdio

[jasnell]

Fixes: #25630
Signed-off-by: James M Snell jasnell@gmail.com

[addaleax]

I mean, this is true for literally all Node.js events (or any other runtime with an event loop). I don’t see why we would want to document this for MessagePorts specifically, unless we plan to add a section for this to literally every other event as well.

The issue this references seems to be specifically about the fact that stdio from Workers uses message passing under the hood, and can get blocked by synchronous code on the receiving end, not the sending one. It’s true that that’s not obvious, so if we do document anything, that is what we should document.

[jasnell]

The issue this references seems to be specifically about the fact that stdio from Workers uses message passing under the hood, and can get blocked by synchronous code on the receiving end, not the sending one. It’s true that that’s not obvious, so if we do document anything, that is what we should document.

Yeah, I was struggling with that a bit also but I think you definitely capture it here... will update :-)

[jasnell]

Landed in 61a67c1