machdep.cpu_idle_hlt on a Dual AMD 2000+ MP

Peter Wood peter at alastria.net
Sun Apr 27 11:35:40 PDT 2003


Afternoon,

I was reading all the threads regarding hyperthreading, and descovered that
machdep.cpu_idle_hlt is set to 0 by default on SMP machines and 1 on
uniprocessor machines.

I've change it to 1 on my dual machine, and so far it appears stable. I have
noticed that the CPU tempratures appear to be lower now, possibly a
coincidence as the servers load may have been changing. Should I expect it to
be lower?

Also should I expect to see any performance loss, or instability? Does anyone
know the original reason for setting the defaults this way?

Just curious,

Have a good one,

Peter.
-- 
Peter Wood <peter at alastria.net> :: Tel +44 7974 799440


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