Re: AMD X2 unsynced TSC fix?

Luca Tettamanti
2006-10-27T20:18:09Z

Lee Revell <rlrevell@joe-job.com> ha scritto:
> Someone recently pointed out to me that a Windows "CPU driver update"
> supplied by AMD fixes the unsynced TSC problem on dual core AMD64
> systems.
[...]
> other incorrect timing effects that these applications may experience on
> dual-core processor systems, by periodically adjusting the core
> time-stamp-counters, so that they are synchronized."
>
> What are the chances of Linux getting a similar fix?

Zero? ;)
There's always a window where the TSCs are not in sync (and userspace may
see a non-monotonic counter); furthermore when C'n'Q is active TSCs
aren't updated at a fixed frequency, userspace cannot use TSC for timing
anyway.

Luca
--
> While we're on all of this, are we going to change "tained" to some
> other less alarmist word?
"screwed" -- Alexander Viro