libvirtError: invalid argument: value of 'vcpu_period' is out of range [1000, 1000000] is logged in vdsm.log

Issue

• The following errors are logged in vdsm.log on a RHEV-Hypervisor:

PolicyEngine::ERROR::2015-03-28 20:54:56,016::vm::5104::vm.Vm::(_reportException) vmId=`f989786c-9245-40b7-ba5d-be059364216b`::Operation failed
Traceback (most recent call last):
  File "/usr/share/vdsm/virt/vm.py", line 5080, in setCpuTunePeriod
    self._dom.setSchedulerParameters({'vcpu_period': int(period)})
  File "/usr/share/vdsm/virt/vm.py", line 689, in f
    ret = attr(*args, **kwargs)
  File "/usr/lib/python2.6/site-packages/vdsm/libvirtconnection.py", line 111, in wrapper
    ret = f(*args, **kwargs)
  File "/usr/lib64/python2.6/site-packages/libvirt.py", line 2039, in setSchedulerParameters
    if ret == -1: raise libvirtError ('virDomainSetSchedulerParameters() failed', dom=self)
libvirtError: invalid argument: value of 'vcpu_period' is out of range [1000, 1000000]

• These errors are only logged on Hypervisors with more than 100 CPU cores.
• Additionally sometimes high %steal times are observed in the VMs running on that Hypervisor.