Basic Offline Server Consolidation

Synopsis

display name: Basic offline consolidation

goal: server_consolidation

Requirements

Metrics

The basic strategy requires the following metrics:

metric

service name

plugins

comment

compute.node.cpu.percent

ceilometer

none

need to set the compute_monitors option to cpu.virt_driver in the nova.conf.

cpu_util

ceilometer

none

cpu_util has been removed since Stein.

Cluster data model

Default Watcher’s Compute cluster data model:

Actions

Default Watcher’s actions:

action

description

migration

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).

Note

Nova API version must be 2.56 or above if destination_node parameter is given.

change_nova_service_state

Planner

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.

Limitations

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

Configuration

Strategy parameter is:

parameter

type

default Value

description

migration_attempts

Number

0

Maximum number of combinations to be tried by the strategy while searching for potential candidates. To remove the limit, set it to 0

period

Number

7200

The time interval in seconds for getting statistic aggregation from metric data source

Efficacy Indicator

[{'name': 'released_nodes_ratio', 'description': 'Ratio of released compute nodes divided by the total number of enabled compute nodes.', 'unit': '%', 'value': 0}]

How to use it ?

$ openstack optimize audittemplate create \
  at1 server_consolidation --strategy basic

$ openstack optimize audit create -a at1 -p migration_attempts=4