a sysctl machdep.tsc_freq problem
gemini at geminix.org
Sat Feb 21 15:29:27 PST 2004
ouyang kai wrote:
> i found a strange case, i have tested the three machines(PIII 800 &
> P4-1.6G & FreeBSD4.8-release, P4-2.0G & FreeBSD5.2.1).
> I use "sysctl -a | grep machdep.tsc.freq" to get the CUP speed. But, I
> failed on the P4-1.6G machine. Nothing appears.
> Should I set some additional stuff on the P4-1.6G machine? I have do
> nothing specailly for the other two machines, but it works.
Is the P4-1.6G machine a multi-processor system, that is, was the kernel
compiled with the SMP option? If so, there is currently no TSC support
on multi-processor systems, for technical reasons I understand. So in
this case 'machdep.tsc.freq' is omitted from the kernel and therefore
cannot be queried.
Uwe Doering | EscapeBox - Managed On-Demand UNIX Servers
gemini at geminix.org | http://www.escapebox.net
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