cpu throttling

[Roger Heflin]

Les wrote:
> Hi, everyone...
> I am on Fedora 8.  I hope to go to F9, but think after watching the
> mail, I will wait a bit.  You all know I'm not astute on this stuff yet.
> 
> 	My question is probably a stupid one.... I have a rather old, but well
> performing Pentium system with dual processors.  Single chip type.  I
> got the CPU throttling messages, and believed them.  I took the system
> apart, cleaned the heatsinks and fans, relubed the interconnect and
> reassembled everything.  Messages gone, no problem.  But then I thought
> how would I monitor this as the local temps went into the 90's and we
> don't have AC (this only happens a couple of days a year here in San
> Juan Capistrano).  So I brought up the CPU speed monitor and the CPU
> temp monitor.  But the speed monitors said that the board lacked
> throttling capability.  NOW this is a connundrum.  How did I get the
> throttling messages if no throttling is available, and how does the
> monitoring code know the current speed of 2.99Ghz?  
> 
> Regards,
> Les H
> 

That means is lacks OS controlled cpu throttling for power savings, not 
fail-safe in the cpu throttling by the cpu itself to save the cpu.

Only very new Intels have useful cpu throttling for power savings (were the 
actual clock speed is slowed down), but for a log longer time they have had 
overheat cpu throttling that was controller internally by the cpu, and took 
effect when things got too hot.

In the past (on older kernels) when I have had machines overheating it has been 
difficult to see without the kernel messages about throttling.   cpuinfo used to 
report the unthrottled cpu speed even when throttled, so the kernel messages or 
noticing that some machines were slower than they should have been were the only 
options.

                                  Roger