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CPU and Memory overcommit defaults in Pike?

What are the overcommit defaults in Pike for cpu and memory on compute nodes? This linke states that cpu is 16:1 and memory is 1.5:1 : :

When I checked nova.conf on the compute nodes it says this (and it's confusing to me):

This option helps you specify virtual CPU to physical CPU allocation ratio.

From Ocata (15.0.0) this is used to influence the hosts selected by the Placement API. Note that when Placement is used, the CoreFilter is redundant, because the Placement API will have already filtered out hosts that would have failed the CoreFilter.

This configuration specifies ratio for CoreFilter which can be set per compute node. For AggregateCoreFilter, it will fall back to this configuration value if no per-aggregate setting is found.

NOTE: This can be set per-compute, or if set to 0.0, the value set on the scheduler node(s) or compute node(s) will be used and defaulted to 16.0.

NOTE: As of the 16.0.0 Pike release, this configuration option is ignored for the ironic.IronicDriver compute driver and is hardcoded to 1.0.

Possible values:

  • Any valid positive integer or float value (floating point value) Minimum value: 0 cpu_allocation_ratio=0.0

I checked ironic.conf and couldnt find a similar cpu overcommit value, so I am confused about what overcommit is presently set to and where it is now configurable.

can you help?