----- Original Message -----
From: "Boris Okun" <bokun@home.com>
To: "Mark Hahn" <hahn@coffee.psychology.mcmaster.ca>
Cc: <linux-kernel@vger.rutgers.edu>; "Krisztian Flautner"
<manowar@engin.umich.edu>
Sent: Tuesday, March 28, 2000 11:18 AM
Subject: Re: Timestamp counters on SMP
> Mark Hahn wrote:
>
> > > Where do you need this? And how will your user space run on platforms
> > > without TSC?
> >
> > ia32, sparc, pa-risc, alpha and probably mips and ppc all have
> > user-visible clock cycle counters. anyone interested in high-res
> > timing has been using them for years.
>
> That does not answer my questions. Let me try again:
>
> Do you know of any application using TSC?
Yes. I've written some (one reads the performance counters and uses the tsc
to provide an accurate
divisor for them-- so much more accurate than getting the time in any other
way). For example,
when I count the # of CPU cycles the CPU is unhalted over 1msec, divide by
the delta TSC, I indeed get
the actual MHz of the machine.
> If yes, how does this application work on i386?
It doesn't. or a 486. I can't remember if base-level Pentiums have TSC,
the PPro does for sure however.
Does every application written need to run on an i386? I sure hope not!
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