Ask HN: Does 10% CPU usage equals 10% (of TDP) power consumption?

1 points by ramshanker 9y ago ↗ HN

While going through stackoverflow architecture[1], I noticed that they try to keep CPU usage very low. Like <5%. Does that mean a 100+ TDP CPU is consuming <5 Watt? If that is the case long term than, it would change all the power budget planning. I mean the popular wisdom of "power costing more than hardware" might change drastically if we run those CPU at very low usage.

[1] https://nickcraver.com/blog/2016/02/17/stack-overflow-the-architecture-2016-edition/

EDIT: Looking for a home server.

2 comments

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Zekio 9y ago ↗

TDP != Power Consumption

Bigrio 9y ago ↗

Well that depends a lot on the cpu, some have very low power states that can drop the power used to just a watt or two at idle, these are more common in laptops. Server cpu's may not drop down as low, or as quickly, in order to respond quickly to new requests. Before the days of speed stepping, the cpu would use similar power regardless of utilization. This article from 2008 highlights some info for xeon. https://software.intel.com/sites/default/files/m/d/4/1/d/8/p...