java.lang.Object
java.lang.Record
org.elasticsearch.cluster.routing.allocation.allocator.DesiredBalance
Record Components:
lastConvergedIndex - Identifies what input data the balancer computation round used to produce this DesiredBalance. See DesiredBalanceInput.index() for details. Each reroute request in the same master term is assigned a strictly increasing sequence number. A new master term restarts the index values from zero. The balancer, which runs async to reroute, uses the latest request's data to compute the desired balance.
assignments - a set of the (persistent) node IDs to which each ShardId should be allocated
weightsPerNode - The node weights calculated based on WeightFunction.calculateNodeWeight(int, float, double, double, double, double)

public record DesiredBalance(long lastConvergedIndex, Map<ShardId,ShardAssignment> assignments, Map<DiscoveryNode,DesiredBalanceMetrics.NodeWeightStats> weightsPerNode, org.elasticsearch.cluster.routing.allocation.allocator.DesiredBalance.ComputationFinishReason finishReason) extends Record
The desired balance of the cluster, indicating which nodes should hold a copy of each shard.
  • Field Details

    • NOT_MASTER

      public static final DesiredBalance NOT_MASTER
      The placeholder value for DesiredBalance when the node stands down as master.
    • BECOME_MASTER_INITIAL

      public static final DesiredBalance BECOME_MASTER_INITIAL
      The starting value for DesiredBalance when the node becomes the master.
  • Constructor Details

    • DesiredBalance

      public DesiredBalance(long lastConvergedIndex, Map<ShardId,ShardAssignment> assignments)
    • DesiredBalance

      public DesiredBalance(long lastConvergedIndex, Map<ShardId,ShardAssignment> assignments, Map<DiscoveryNode,DesiredBalanceMetrics.NodeWeightStats> weightsPerNode, org.elasticsearch.cluster.routing.allocation.allocator.DesiredBalance.ComputationFinishReason finishReason)
      Creates an instance of a DesiredBalance record class.
      Parameters:
      lastConvergedIndex - the value for the lastConvergedIndex record component
      assignments - the value for the assignments record component
      weightsPerNode - the value for the weightsPerNode record component
      finishReason - the value for the finishReason record component
  • Method Details

    • getAssignment

      public ShardAssignment getAssignment(ShardId shardId)
    • hasChanges

      public static boolean hasChanges(DesiredBalance a, DesiredBalance b)
    • shardMovements

      public static int shardMovements(DesiredBalance old, DesiredBalance updated)
      Returns the sum of shard movements needed to reach the new desired balance. Doesn't count new shard copies as a move, nor removal or unassignment of a shard copy.
    • humanReadableDiff

      public static String humanReadableDiff(DesiredBalance old, DesiredBalance updated)
    • toString

      public final String toString()
      Returns a string representation of this record class. The representation contains the name of the class, followed by the name and value of each of the record components.
      Specified by:
      toString in class Record
      Returns:
      a string representation of this object
    • hashCode

      public final int hashCode()
      Returns a hash code value for this object. The value is derived from the hash code of each of the record components.
      Specified by:
      hashCode in class Record
      Returns:
      a hash code value for this object
    • equals

      public final boolean equals(Object o)
      Indicates whether some other object is "equal to" this one. The objects are equal if the other object is of the same class and if all the record components are equal. Reference components are compared with Objects::equals(Object,Object); primitive components are compared with '=='.
      Specified by:
      equals in class Record
      Parameters:
      o - the object with which to compare
      Returns:
      true if this object is the same as the o argument; false otherwise.
    • lastConvergedIndex

      public long lastConvergedIndex()
      Returns the value of the lastConvergedIndex record component.
      Returns:
      the value of the lastConvergedIndex record component
    • assignments

      public Map<ShardId,ShardAssignment> assignments()
      Returns the value of the assignments record component.
      Returns:
      the value of the assignments record component
    • weightsPerNode

      Returns the value of the weightsPerNode record component.
      Returns:
      the value of the weightsPerNode record component
    • finishReason

      public org.elasticsearch.cluster.routing.allocation.allocator.DesiredBalance.ComputationFinishReason finishReason()
      Returns the value of the finishReason record component.
      Returns:
      the value of the finishReason record component