[Semi-OT] Fibers vs. Async / Await

[Steven Schveighoffer]

On 5/12/22 7:37 AM, René Zwanenburg wrote:
> On Wednesday, 11 May 2022 at 13:49:28 UTC, rikki cattermole wrote:
>> Don't forget the extra cost of having to scan those stacks regardless 
>> of those fibers state.
>>
>> The context state required for a task will be a lot smaller (and hence 
>> cheaper) than what a single fiber stack will cost to scan.
> 
> That's a good point. As an improvement, could we mark the unused part of 
> the fiber's stack as NO_SCAN when it yields? And ofc undo it when the 
> fiber switches back in. Or would that be too heavy an operation?

Fibers already do this.

https://github.com/dlang/druntime/blob/392c528924d0ce4db57a03bfdaa6587169568493/src/core/thread/fiber.d#L429-L436

-Steve