> I still like threads, but the I'm old and uncool.
Hey, I resemble that remark.
But I disagree with it. Green threads give you all the advantages of async, but with less of the hairs. In particular no special syntax or change of programming style is required. Yet underneath green threads and async just different styles of event driven I/O, so both run at similar speeds and excel at the same tasks. (Actually green threads should run faster, as storing state on a stack is generally faster than malloc.)
I have no idea why Rust abandoned green threads in favour of async. Actually, that's a partial lie - there have been far too many words wasted on explaining why. The problem is the reasons they give look to be an caused by design decisions they made in their implementation. The primary objection seems to be speed. The current async is indeed faster than their old green thread implementation. But that was caused by their choosing to avoid coloured code in their green threads (maybe they were copying Go?). Other objections were similarly to do with the implementation they threw away, not green threads themselves.
Hey, I resemble that remark.
But I disagree with it. Green threads give you all the advantages of async, but with less of the hairs. In particular no special syntax or change of programming style is required. Yet underneath green threads and async just different styles of event driven I/O, so both run at similar speeds and excel at the same tasks. (Actually green threads should run faster, as storing state on a stack is generally faster than malloc.)
I have no idea why Rust abandoned green threads in favour of async. Actually, that's a partial lie - there have been far too many words wasted on explaining why. The problem is the reasons they give look to be an caused by design decisions they made in their implementation. The primary objection seems to be speed. The current async is indeed faster than their old green thread implementation. But that was caused by their choosing to avoid coloured code in their green threads (maybe they were copying Go?). Other objections were similarly to do with the implementation they threw away, not green threads themselves.