Re: X15 alpha release: as fast as TUX but in user space (fwd)

Pavel Machek
2001-05-01T11:19:25Z

Hi!

> > > In x86-64 there are special vsyscalls btw to solve this problem that export
> > > a lockless kernel gettimeofday()
> >
> > Whatever happened to that hack that was discussed a year or two ago?
> > The one where (also on IA32) a magic page was set up by the kernel
> > containing code for fast system calls, and the kernel would write
> > calibation information to that magic page. The code written there
> > would use the TSC in conjunction with that calibration data.
> >
> > There was much discussion about this idea, even Linus was keen on
> > it. But IIRC, nothing ever happened.
> >
>
> We discussed this at the Summit, not a year or two ago. x86-64 has
> it, and it wouldn't be too bad to do in i386... just noone did.

Just wait what kind of problems it is able to bring on i386.

Pavel
PS: Hmm, how do you do timewarp for just one userland appliation with
this installed?

--
I'm pavel@ucw.cz. "In my country we have almost anarchy and I don't care."
Panos Katsaloulis describing me w.r.t. patents at discuss@linmodems.org