Re: Speed Step and powerd for servers status?

Abdullah Ibn Hamad Al-Marri wrote:
Hey,


I would like to use powerd and speed step for my servers, and make sure it will use the MAX CPU if needed then go to idle mode to save the power.

Any recommendation?

It's questionable whether or not it will have positive effect on the server:

<quote>
The combination of processor-frequency scaling and idle-power states provides a somewhat surprising result. On almost all modern hardware, if there is code to run, then it is more power efficient to run the processor at full speed. This "race to idle" concept stems from the power consumption of an idle processor being much lower than an active processor, even if running at a lower speed. The overall power consumption will be less if the processor spends a short time at full speed and then falls back to idle, rather than spending twice as long being active at a lower frequency.
</quote>

Full text is here:

http://www.acmqueue.com/modules.php?name=Content&pa=showpage&pid=513

-Maxim
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