In the nova proposal cpu_allocation_ratio can be set. But this setting has only effect, if CoreFilter or AggregateCoreFilter are used as scheduler_default_filters. But this is not the case in the default settings of scheduler_default_filters. At least if someone changes the default value from cpu_allocation_ratio, CoreFilter should be added to the filters.
In the nova proposal cpu_allocation_ratio can be set. But this setting has only effect, if CoreFilter or AggregateCoreFilter are used as scheduler_default_filters. But this is not the case in the default settings of scheduler_default_filters. At least if someone changes the default value from cpu_allocation_ratio, CoreFilter should be added to the filters.