Number of allocated vCPUs on XenServer

xen_server_vcpu_sum.sh

xe vm-list params=VCPUs-number --minimal | tr ',' '\n' | paste -sd+ | bc

Human-readable version:

for id in $(xe vm-list | grep uuid | awk '{print $5}'); do 
  if [[ $(xe vm-param-list uuid=${id} | grep -Po "(?<=power-state\ \(\ RO\):\ )\w+") == "running" ]]; then 
    xe vm-param-list uuid=${id} | grep -Po "(?<=VCPUs-number\ \(\ RO\):\ )[0-9]+"
  fi
done | paste -s -d+ | bc

As my colleague pointed out there's a much faster way to achieve the same as presented above, hence this gist was updated.

One last thing - when VM is not in running state it reports 0 vCPUs.