On 11/28/2018 10:38 AM, Massimo Sgaravatto wrote: > Hi > > I was wondering if nova allows to get the CPUtime and wallclocktime > consumed by a project in a certain time period, without using ceilometer > > Among the data returned by the command "openstack usage show" there is > also a "CPU Hours" but, if I am not wrong, this is actually the > WallClockTime. Did I get it right ? It's neither. It's the calculated time that the VM has been "up" multiplied by the number of vCPUs the VM consumes. It's basically worthless as anything more than a simplistic indicator of rough resource consumption. You can see how the calculation is done by following the fairly convoluted code in the os-simple-tenant-usage API: This calculates the "hours used": https://github.com/openstack/nova/blob/62245235bc15da6abcdfd3df1c24bd856d69fbb4/nova/api/openstack/compute/simple_tenant_usage.py#L51-L82 And here is where that is multiplied by the VM's vCPUs: https://github.com/openstack/nova/blob/62245235bc15da6abcdfd3df1c24bd856d69fbb4/nova/api/openstack/compute/simple_tenant_usage.py#L213 > If so, it is also possible to get the CPUTime ? If you are referring to getting the amount of time a *physical host CPU* has spent performing tasks for a particular VM, the closest you can get to this would be the "server diagnostics" API: https://github.com/openstack/nova/blob/master/nova/api/openstack/compute/views/server_diagnostics.py That said, the server diagnostics API is a very thin shim over a virt-driver-specific interface: https://github.com/openstack/nova/blob/62245235bc15da6abcdfd3df1c24bd856d69fbb4/nova/compute/manager.py#L4698 The libvirt driver's get_server_diagnostics() (host-specific) and get_instance_diagnostics() (VM-specific) implementation is here: https://github.com/openstack/nova/blob/62245235bc15da6abcdfd3df1c24bd856d69fbb4/nova/virt/libvirt/driver.py#L8543-L8678 You might want to look at that code and implement a simple collectd/statsd/fluentd/telegraf collector to grab those stats directly from the libvirt daemon on the compute nodes themselves. Best, -jay