Before anyone gets too excited about ntsync, the performance gains are (with few exceptions) mild, usually in the lower single percentage range. These extreme gains are the result of benching against vanilla wine without fsync, anyone playing demanding games on linux would have been doing so using fsync. This is mentioned in the article but treated like a side note. I've been running benchmarks between both and while the performance increase is real, please temper your expectations. A few titles might also run slightly worse.
Unless you are running an ancient LTS distribution, you at least have fsync. But then also recognize, with the ancient LTS distribution not carrying any enhancements for the last few years, your drivers are also out of date and games will play terribly for unrelated reasons.
The common gaming-focused Wine/Proton builds can also use esync (eventfd-based synchronization). IIRC, it doesn't need a patched kernel.
The point being that these massive speed gains will probably not be seen by most people as you suggest, because most Linux gamers already have access to either esync or fsync.
Maybe you are right about esync but anyway I would also gather a lot of people don’t have that either. At least personally I don’t bother with custom proton builds or whatever so if Valve didn’t enable that on their build then I don’t have it.
> if Valve didn’t enable that on their build then I don’t have it.
The Proton build is Valve's build. It supports both fsync and esync, the latter of which does not require a kernel patch. If you're gaming on Linux with Steam, you're probably already using it.
I would assume most of them? I'd be surprised if distros like Debian, Ubuntu, Fedora, etc. would ship non-mainline kernel features like that.
Sure, gaming-focused distros, or distros like Arch or Gentoo might (optionally or otherwise), but mainstream? Probably not.
Of course, esync doesn't require kernel patches, so I imagine that was more broadly out there. But it sounds like fsync got you performance pretty close to what ntsync can do, but esync was quite a bit behind both? With vanilla being quite a bit behind esync?
(Also, jeez, fsync, what a terrible name. fsync is a syscall that has to do with filesystem data. So confusing.)
Last I checked, every distro of note had its own patchset that included stuff outside the vanilla kernel tree. Did that change? I admit I haven't looked at any of that in... oh, 15 years or so.
If you read more carefully it says fsync needs some enhancements to the futex API, called futex2. The original patch that fsync needed called the syscall futex_wait_multiple. Eventually futex2 made it into the mainline kernel, but the syscall is called futex_waitv. Not sure if the wine fsync implementation was updated to support the mainline kernel futex2 implementation.