6.10. Enforcing Low Tenancy on Nodes

Set the max_active_gears value in a node's gear profile to a low number to achieve low or single tenancy on nodes. In environments with low numbers of gears per node and large gear sizes, it is important to avoid overcommitting resources and exceeding the max_active_gears value.
Set the no_overcommit_active value in the node's gear profile to true to avoid overcommitting resources and to enforce the desired tenancy. This setting verifies node capacity when a gear is being created on a node. If sufficient capacity is not available on the selected node, the gear is not created and an error message is displayed.

Example 6.15. Node Capacity Exceeded Error Message

Gear creation failed (chosen node capacity exceeded).
This message is also displayed if another application is already being created on the selected node.

Procedure 6.12. To Enforce Low Tenancy on Nodes:

  1. Open the /etc/openshift/resource_limits.conf file on the node host and set the no_overcommit_active value to true: 
    no_overcommit_active=true
  2. Restart the ruby193-mcollective service: 
    # service ruby193-mcollective restart