want to set production and development VM priority when they are created/launched in openstack so that certain VM can have more resource(like vCPUs,memory etc.)allocation contention than other normal VMs. Already checked openstack- no such tool/service available till now.So checking other options...

The number of vcpus is determined by the flavor, as is the memory size. While memory can be overbooked, you can configure it so that each instance gets the amount it requires at any time.

Nova doesn’t allow you to prioritize VMs, but neither does libvirt I think. You could, however, set the nice values of qemu processes. See also https://stackoverflow.com/questions/4....