> > not the case on Intel SMP at least.
>
> I thought we are talking about generic code. And I believe this would
> be possible even on intel: consider 60MHz but clock and each processor
> having different internal clock multiplier.
yes this is technically possible, but is not done in RL for obvious
reasons. We would break on a couple of other places in the time (and
profiling) code. The first time we encounter such a board (which mixes
different speed pentiums and stuff) we have to think about this case too.
> > get_slow() executes in ~6-7 microseconds, we do not want to do that ...
> > but then again, this whole issue is only a problem on higly loaded
> > ISP's
>
> No. Whole issue is problem as soon as you run qt application (kde*,
> qtscape, qweb, ...), which does busy waiting. Because its busy waiting
> loop is close, manages to finish in less than jiffie and that means it
> is invisible. Authors of qt maybe are not even aware of what they are
> doing.
i see. Lets try the rdtsc driven stuff in 2.3. We really cannot do much on
CPUs that have 1) only 1 clock source 2) no way to measure microtime in an
efficient way.
-- mingo
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