User-managed concurrency groups

Posted Dec 28, 2021 16:45 UTC (Tue) by khim (subscriber, #9252)
Parent article: User-managed concurrency groups

I find it really strange that word “fiber” is never mentioned in the context of these patchsets. Even if it's clearly mentioned in the very first message.

Basically the whole things, it seems, rests on the following observation: Windows reserves 12KiB of of stack for the “Stack Overflow” exception handling — but that's not needed on GNU/Linux and you may use that same amount of memory to equip each fiber with it's own, personal, thread (8KiB in kernel + 4KiB in GLibC).

Add couple of syscalls and now you have fibers which are full-blown threads so they can be used with tools which are used for threads, there are no need for special “fibers” API (like GetFiberData) and so on.

They are probably still a tiny bit heavier than purely-userspace fibers, but advantage sounds really compelling: no need to use onlyh fiber-aware libraries, etc… I guess there should be some experience with Windows Fibers which would be relevant when this patchset is considered.