Get data about current overcommit per hypervisor from OpenStack

current_overcommit_from_nova.py

#!/usr/bin/python3
import os
from openstack import connect
from pprint import pprint

def main():
    conn = connect()
    allocation_ratios = {
        hv.name: {
            "CPU": round(hv.vcpus_used / hv.vcpus, 2),
            "RAM": round(hv.memory_used / hv.memory_size, 2)
        }
        for hv in conn.compute.hypervisors(details=True)
    }
    pprint(allocation_ratios)

if __name__ == "__main__":
    os.environ['OS_COMPUTE_DEFAULT_MICROVERSION'] = '2.86'
    main()

current_overcommit_from_placement.py

#!/usr/bin/python3
from openstack import connect
from pprint import pprint
from joblib import Parallel, delayed

def fetch_ratios(conn, provider, allocation_ratios):
    inv = conn.placement.get(f"/resource_providers/{provider.id}/inventories").json()['inventories']
    usage = conn.placement.get(f"/resource_providers/{provider.id}/usages").json()['usages']
    allocation_ratios.update({provider.name: {
        "CPU": round((usage['VCPU'] - inv['VCPU']['reserved']) / inv['VCPU']['total'], 2),
        "RAM": round((usage['MEMORY_MB'] - inv['MEMORY_MB']['reserved']) / inv['MEMORY_MB']['total'], 2)
    }})


def main():
    conn = connect()
    allocation_ratios = {}
    providers = conn.placement.resource_providers()
    Parallel(n_jobs=5, prefer="threads")(
            delayed(fetch_ratios)(conn, provider, allocation_ratios)
            for provider in providers)

    pprint(allocation_ratios)


if __name__ == "__main__":
    main()