Package com.marcnuri.yakc.model.io.k8s.api.core.v1

Class TopologySpreadConstraint.Builder

  • Enclosing class:
    TopologySpreadConstraint
    public static class TopologySpreadConstraint.Builder
extends java.lang.Object

    • Method Detail

      • maxSkew

        public TopologySpreadConstraint.Builder maxSkew​(@NonNull
                                                @NonNull java.lang.Number maxSkew)
        MaxSkew describes the degree to which pods may be unevenly distributed. When `whenUnsatisfiable=DoNotSchedule`, it is the maximum permitted difference between the number of matching pods in the target topology and the global minimum. For example, in a 3-zone cluster, MaxSkew is set to 1, and pods with the same labelSelector spread as 1/1/0: | zone1 | zone2 | zone3 | | P | P | | - if MaxSkew is 1, incoming pod can only be scheduled to zone3 to become 1/1/1; scheduling it onto zone1(zone2) would make the ActualSkew(2-0) on zone1(zone2) violate MaxSkew(1). - if MaxSkew is 2, incoming pod can be scheduled onto any zone. When `whenUnsatisfiable=ScheduleAnyway`, it is used to give higher precedence to topologies that satisfy it. It's a required field. Default value is 1 and 0 is not allowed.
        Returns:
        this.

      • topologyKey

        public TopologySpreadConstraint.Builder topologyKey​(@NonNull
                                                    @NonNull java.lang.String topologyKey)
        TopologyKey is the key of node labels. Nodes that have a label with this key and identical values are considered to be in the same topology. We consider each <key, value> as a "bucket", and try to put balanced number of pods into each bucket. It's a required field.
        Returns:
        this.

      • whenUnsatisfiable

        public TopologySpreadConstraint.Builder whenUnsatisfiable​(@NonNull
                                                          @NonNull java.lang.String whenUnsatisfiable)
        WhenUnsatisfiable indicates how to deal with a pod if it doesn't satisfy the spread constraint. - DoNotSchedule (default) tells the scheduler not to schedule it. - ScheduleAnyway tells the scheduler to schedule the pod in any location,

        but giving higher precedence to topologies that would help reduce the

        skew.

        A constraint is considered "Unsatisfiable" for an incoming pod if and only if every possible node assigment for that pod would violate "MaxSkew" on some topology. For example, in a 3-zone cluster, MaxSkew is set to 1, and pods with the same labelSelector spread as 3/1/1: | zone1 | zone2 | zone3 | | P P P | P | P | If WhenUnsatisfiable is set to DoNotSchedule, incoming pod can only be scheduled to zone2(zone3) to become 3/2/1(3/1/2) as ActualSkew(2-1) on zone2(zone3) satisfies MaxSkew(1). In other words, the cluster can still be imbalanced, but scheduler won't make it *more* imbalanced. It's a required field.

        Returns:
        this.

      • toString

        public java.lang.String toString()
        Overrides:
        toString in class java.lang.Object