winterhazel opened a new pull request, #14384:
URL: https://github.com/apache/cloudstack/pull/14384

   ### Description
   
   This is a breaking change, so additional discussion may be required. It also 
contains the changes of #14383, so please review and merge the latter 
previously.
   
   Many CPUs (notably AMD EPYC) do not advertise a frequency in the model name, 
so those hosts fell back to `CPU max MHz`, which can include the turbo 
frequency. Since the host CPU speed is used to compute host capacity (`cpus * 
speed`) and the CPU quota of VMs with CPU cap enabled, using a turbo value is 
not correct because it is not a frequency the CPU can actually sustain.
   
   This PR inserts the CPU frequency sysfs files 
(`/sys/devices/system/cpu/cpu0/cpufreq/base_frequency`, then 
`scaling_max_freq`) before the `lscpu` maximum frequency fallback, so the 
resolution order becomes:
   
   1. base frequency advertised in the `lscpu` `Model name` field (x86) or `CPU 
dynamic MHz` (s390x)
   2. CPU frequency sysfs file (`base_frequency`, then `scaling_max_freq`)
   3. `lscpu` `CPU max MHz`
   4. `lscpu` host capabilities
   5. libvirt `NodeInfo.mhz`
   
   Behaviour for Intel hosts (whose model name carries `@ x.xxGHz`) is 
unchanged.
   
   Additionally, I made a few refactorings throughout the `KVMHostInfo` file.
   
   ### Types of changes
   
   - [X] Breaking change (fix or feature that would cause existing 
functionality to change)
   - [ ] New feature (non-breaking change which adds functionality)
   - [ ] Bug fix (non-breaking change which fixes an issue)
   - [ ] Enhancement (improves an existing feature and functionality)
   - [ ] Cleanup (Code refactoring and cleanup, that may add test cases)
   - [ ] Build/CI
   - [ ] Test (unit or integration test code)
   
   ### Feature/Enhancement Scale or Bug Severity
   
   ### Screenshots (if appropriate):
   
   ### How Has This Been Tested?
   
   Tests are still pending.


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