System extremely slow under light load

[Clifton Royston]

On Mon, Apr 25, 2011 at 02:45:14PM +0200, Bartosz Fabianowski wrote:
> >dev.cpu.X.freq does reflect the current frequency; I don't know whether
> >or how any internal clock throttling might be exposed.
> 
> From what I have seen, dev.cpu.X.freq always retains the value I set it 
> to. Internal CPU throttling does not seem to be reported this way.
...
> I just tried this on my current Dell Studio 1558, with devastating 
> results. The first boot attempt ended with the machine shutting down due 
> to overheating while loading the kernel. I let it cool down a bit and 
> then booted again. This time, I got to my desktop - with a CPU 
> temperature of 95??C. If the DSDT was fixed, the machine would have shut 
> down at this point.

  I could be wrong, but in my experience this really sounds like it is
a hardware problem with the cooling system, and a very serious one at
that.  I would encourage you to take this up with Dell at once.

  While it's certainly possible that newer FreeBSD releases are failing
to control the temperature as well as older ones due to some change,
that does not mean that this is a FreeBSD problem - these temperatures
are so far out of line that anything FreeBSD managed to do before
should be viewed as an unexpectedly successful workaround.

  The only way I can see the core problem as OS-related is if the
hardware design is relying on Windows-specific drivers to control the
cooling system, which would be crazy though not impossible.

...
> Yes, these are the frequencies I have available now. 1333 makes the 
> machine idle around 85??C, 1999 leads to 78-80??C.

  Apart from your immediate problems, in my past experience this range
of CPU temperatures is likely to lead to early failure of the CPU, very
likely within a year or less.

  -- Clifton

-- 
   Clifton Royston  --  cliftonr at iandicomputing.com / cliftonr at volcano.org
       President  - I and I Computing * http://www.iandicomputing.com/
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