[anonacct37]

You're right in that people have seen high p90 latency as a result of things like base64 encoding large blocks.

But one thing to remember is that go inserts gc and pre-emption points at function call sites. So basically as long as a function is occasionally called you're good.

Cgo threading does complicate the matter. My understanding is that cgo calls are done in a threadpool with a larger stack size. I don't know the details about how that threadpool is managed. Not sure if this would help or hurt your concern.

Also, don't forget GOMAXPROCS. There's nothing stopping you from letting the go runtime spin up arbitrarily large number of OS threads.

So it's not an ideal situation, but if you're careful I don't think tight loops are likely to torpedo an otherwise sound go project.