def _get_disk_over_committed_size_total(self):
    'Return total over committed disk size for all instances.'
    disk_over_committed_size = 0
    for dom in self._list_instance_domains():
        try:
            xml = dom.XMLDesc(0)
            disk_infos = jsonutils.loads(self._get_instance_disk_info(dom.name(), xml))
            for info in disk_infos:
                disk_over_committed_size += int(info['over_committed_disk_size'])
        except libvirt.libvirtError as ex:
            error_code = ex.get_error_code()
            LOG.warn((_LW('Error from libvirt while getting description of %(instance_name)s: [Error Code %(error_code)s] %(ex)s') % {'instance_name': dom.name(), 'error_code': error_code, 'ex': ex}))
        except OSError as e:
            if (e.errno == errno.ENOENT):
                LOG.warn(_LW('Periodic task is updating the host stat, it is trying to get disk %(i_name)s, but disk file was removed by concurrent operations such as resize.'), {'i_name': dom.name()})
            if (e.errno == errno.EACCES):
                LOG.warn(_LW('Periodic task is updating the host stat, it is trying to get disk %(i_name)s, but access is denied. It is most likely due to a VM that exists on the compute node but is not managed by Nova.'), {'i_name': dom.name()})
            else:
                raise
        greenthread.sleep(0)
    return disk_over_committed_size
Return total over committed disk size for all instances.
def _get_disk_over_committed_size_total(self):
    
    disk_over_committed_size = 0
    for dom in self._list_instance_domains():
        try:
            xml = dom.XMLDesc(0)
            disk_infos = jsonutils.loads(self._get_instance_disk_info(dom.name(), xml))
            for info in disk_infos:
                disk_over_committed_size += int(info['over_committed_disk_size'])
        except libvirt.libvirtError as ex:
            error_code = ex.get_error_code()
            LOG.warn((_LW('Error from libvirt while getting description of %(instance_name)s: [Error Code %(error_code)s] %(ex)s') % {'instance_name': dom.name(), 'error_code': error_code, 'ex': ex}))
        except OSError as e:
            if (e.errno == errno.ENOENT):
                LOG.warn(_LW('Periodic task is updating the host stat, it is trying to get disk %(i_name)s, but disk file was removed by concurrent operations such as resize.'), {'i_name': dom.name()})
            if (e.errno == errno.EACCES):
                LOG.warn(_LW('Periodic task is updating the host stat, it is trying to get disk %(i_name)s, but access is denied. It is most likely due to a VM that exists on the compute node but is not managed by Nova.'), {'i_name': dom.name()})
            else:
                raise
        greenthread.sleep(0)
    return disk_over_committed_size