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KVM wrong CPU speed reported


Hi guys,

https://github.com/apache/cloudstack/commit/29e389eb872ffa816be99aa66ff20bdec56d3187

this one gets above gets CPU frequency with "effectively
"cat sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq" which gives the
TurboBoost CPU frequency (in case of Intel CPU) and similar for AMD.

Problem is that TurboBoost can only boost frequency of a very small number
of CPU cores for a period of time - not by any means all cores.

CPU frequency is wrongly reported here as i.e. 3.4 GHz instead of 2.6 GHZ
(example of Intel(R) Xeon(R) CPU E5-2650 v2 @ 2.60GHz)

We here thus have effective over-provisioning of 30% by default.

Can we fix this somehow to actually read the base CPU frequency ?
i.e. Xen reports correct CPU frequency (base/nominal one)

Best,

-- 

Andrija Panić