Comment 1:

The idea here was to hint that a million outstanding system calls means a million
outstanding kernel contexts held as threads. That's no longer true to the same extent
but I don't know how to explain the situation clearly in a way that does not require
constant maintenance.
Maybe weaken to:
The result, which we call goroutines, can be very cheap: they cost little more than the
memory for the stack, which is just a few kilobytes.

Comment 2:

I think I understand the warning now. Maybe something along the lines of
"The result, which we call goroutines, can be very cheap: they cost little more than the
memory for the stack, which is just a few kilobytes. A goroutine is much cheaper than a
system-call that creates an OS thread (unless, of course, your goroutine launches a
system call)."
Forgive me if that is not correct; I don't have detailed knowledge on the subject.

Comment 3:

This issue was closed by revision 287967f.

Status changed to Fixed.