ea35fd5152
This lets users configure providers which should fulfill requests before other providers. This facilitates using a less expensive cloud before using a more expensive one. The default priority is 100, to facilitate either raising above or lowering below the default (while using only positive integers in order to avoid confusion). Change-Id: I969ea821e10a7773a0a8d135a4f13407319362ee
4.6 KiB
zuul
Metastatic Driver
This driver uses NodePool nodes (from any driver) as backing nodes to further allocate "static-like" nodes for end use.
A typical use case is to be able to request a large node (a backing node) from a cloud provider, and then divide that node up into smaller nodes that are actually used (requested nodes). A backing node can support one or more requested nodes, and backing nodes are scaled up or down as necessary based on the number of requested nodes.
The name is derived from the nodes it provides (which are like "static" nodes) and the fact that the backing nodes come from NodePool itself, which is "meta".
providers.[metastatic]
A metastatic provider's resources are partitioned into groups called pools, and within a pool, the node types which are to be made available are listed.
Note
For documentation purposes the option names are prefixed
providers.[metastatic] to disambiguate from other drivers,
but [metastatic] is not required in the configuration (e.g.
below providers.[metastatic].pools refers to the
pools key in the providers section when the
metastatic driver is selected).
Example:
providers:
- name: meta-provider
driver: metastatic
pools:
- name: main
max-servers: 10
labels:
- name: small-node
backing-label: large-node
max-parallel-jobs: 2
grace-time: 600name
A unique name for this provider configuration.
pools
A pool defines a group of resources from the provider. Each pool has a maximum number of nodes which can be launched from it, along with a number of attributes that characterize the use of the backing nodes.
name
A unique name within the provider for this pool of resources.
priority
The priority of this provider pool (a lesser number is a higher priority). Nodepool launchers will yield requests to other provider pools with a higher priority as long as they are not paused. This means that in general, higher priority pools will reach quota first before lower priority pools begin to be used.
This setting may be specified at the provider level in order to apply to all pools within that provider, or it can be overridden here for a specific pool.
max-servers
Maximum number of servers spawnable from this pool. This can be used to limit the number of servers. If not defined nodepool can create as many servers that the backing node providers support.
labels
Each entry in a pool's labels section indicates that the corresponding label is available for use in this pool.
labels:
- name: small-node
backing-label: large-node
max-parallel-jobs: 2
grace-time: 600Each entry is a dictionary with the following keys:
name
Identifier for this label.
backing-label
Refers to the name of a different label in Nodepool which will be used to supply the backing nodes for requests of this label.
max-parallel-jobs
The number of jobs that can run in parallel on a single backing node.
grace-time
When all requested nodes which were assigned to a backing node have been deleted, the backing node itself is eligible for deletion. In order to reduce churn, NodePool will wait a certain amount of time after the last requested node is deleted to see if new requests arrive for this label before deleting the backing node. Set this value to the amount of time in seconds to wait.