Outlet Temperature Based Strategy

Outlet Temperature Based Strategy


display name: Outlet temperature based strategy

goal: thermal_optimization

Outlet (Exhaust Air) temperature is a new thermal telemetry which can be used to measure the host’s thermal/workload status. This strategy makes decisions to migrate workloads to the hosts with good thermal condition (lowest outlet temperature) when the outlet temperature of source hosts reach a configurable threshold.


This strategy has a dependency on the host having Intel’s Power Node Manager 3.0 or later enabled.


The outlet_temperature strategy requires the following metrics:

metric service name plugins comment
hardware.ipmi.node.outlet_temperature ceilometer IPMI  

Cluster data model

Default Watcher’s Compute cluster data model:

Nova cluster data model collector

The Nova cluster data model collector creates an in-memory representation of the resources exposed by the compute service.


Default Watcher’s actions:

action description

Migrates a server to a destination nova-compute host

This action will allow you to migrate a server to another compute destination host. Migration type ‘live’ can only be used for migrating active VMs. Migration type ‘cold’ can be used for migrating non-active VMs as well active VMs, which will be shut down while migrating.

The action schema is:

schema = Schema({
 'resource_id': str,  # should be a UUID
 'migration_type': str,  # choices -> "live", "cold"
 'destination_node': str,
 'source_node': str,

The resource_id is the UUID of the server to migrate. The source_node and destination_node parameters are respectively the source and the destination compute hostname (list of available compute hosts is returned by this command: nova service-list --binary nova-compute).


Default Watcher’s planner:

Weight planner implementation

This implementation builds actions with parents in accordance with weights. Set of actions having a higher weight will be scheduled before the other ones. There are two config options to configure: action_weights and parallelization.


  • This planner requires to have action_weights and parallelization configs tuned well.


Strategy parameter is:

parameter type default Value description
threshold Number 35.0 Temperature threshold for migration
period Number 30 The time interval in seconds for getting statistic aggregation from metric data source

Efficacy Indicator



For more information on the Outlet Temperature Based Strategy please refer to: https://specs.openstack.org/openstack/watcher-specs/specs/mitaka/implemented/outlet-temperature-based-strategy.html

How to use it ?

$ openstack optimize audittemplate create \
  at1 thermal_optimization --strategy outlet_temperature

$ openstack optimize audit create -a at1 -p threshold=31.0
Creative Commons Attribution 3.0 License

Except where otherwise noted, this document is licensed under Creative Commons Attribution 3.0 License. See all OpenStack Legal Documents.