Clusters

oxidepm start ./server -i 4 --port 3000

or in a config file:

[[apps]]
name = "web"
mode = "node"
script = "server.js"
instances = 4
port = 3000

The shape of a cluster

A cluster is a parent (web, with no process) and one app per instance (web-0, web-1, and so on). There are at most 256 instances. Instance i gets port port + i, or the start of port_range plus i. The range must hold every instance, and port and port_range together are refused.

Starting and stopping

• The cluster is created all at once. A name that is already taken (web-1 included) refuses the start with E_APP_EXISTS and writes nothing. If an instance cannot launch on the first start, the whole cluster is deleted again and the instance's error is returned.
• Starting a cluster that exists starts only the instances that are at rest: after stop web-1, start web brings back web-1 and leaves the others running.
• The number of instances cannot change (E_INVALID_SPEC). Delete and recreate. That includes starting an existing single app with more than one instance, or an existing cluster with one.
• delete web removes the parent and all instance rows in one transaction, before any instance is stopped.
• A tag or all that matches a cluster and its instances acts on the cluster once. web-1 by name acts on that instance only.

Policy

The markers protected and ai_control of a cluster apply to every instance. An instance created later takes the markers of its cluster. An instance can be set on its own, but it counts as protected when its cluster is, and as open to AI control only when both are.