Package org.infinispan.distribution.ch.impl

Class SyncReplicatedConsistentHashFactory

java.lang.Object
org.infinispan.distribution.ch.impl.SyncReplicatedConsistentHashFactory
All Implemented Interfaces:
ConsistentHashFactory<ReplicatedConsistentHash>
public class SyncReplicatedConsistentHashFactory extends Object implements ConsistentHashFactory<ReplicatedConsistentHash>
SyncConsistentHashFactory adapted for replicated caches, so that the primary owner of a key is the same in replicated and distributed caches.
Since:
8.2
Author:
Dan Berindei

  • Constructor Details

    • SyncReplicatedConsistentHashFactory

      public SyncReplicatedConsistentHashFactory()

  • Method Details

    • create

      public ReplicatedConsistentHash create(int numOwners, int numSegments, List<Address> members, Map<Address,Float> capacityFactors)
      Description copied from interface: ConsistentHashFactory
      Create a new consistent hash instance. The consistent hash will be balanced.
      Specified by:
      create in interface ConsistentHashFactory<ReplicatedConsistentHash>
      Parameters:
      numOwners - The ideal number of owners for each key. The created consistent hash can have more or less owners, but each key will have at least one owner.
      numSegments - Number of hash-space segments. The implementation may round up the number of segments for performance, or may ignore the parameter altogether.
      members - A list of addresses representing the new cache members.
      capacityFactors - The capacity factor of each member. Determines the relative capacity of each node compared to the others. The implementation may ignore this parameter. If null, all the members are assumed to have a capacity factor of 1.

    • fromPersistentState

      public ReplicatedConsistentHash fromPersistentState(ScopedPersistentState state)
      Description copied from interface: ConsistentHashFactory
      Recreates a ConsistentHash from a previously stored persistent state. The returned ConsistentHash will not have proper addresses, but PersistentUUIDs instead so they will need to be replaced
      Specified by:
      fromPersistentState in interface ConsistentHashFactory<ReplicatedConsistentHash>
      Parameters:
      state - the state to restore

    • updateMembers

      public ReplicatedConsistentHash updateMembers(ReplicatedConsistentHash baseCH, List<Address> newMembers, Map<Address,Float> actualCapacityFactors)
      Description copied from interface: ConsistentHashFactory
      Updates an existing consistent hash instance to remove owners that are not in the newMembers list.

      If a segment has at least one owner in newMembers, this method will not add another owner. This guarantees that the new consistent hash can be used immediately, without transferring any state.

      If a segment has no owners in newMembers and the ConsistentHash implementation (e.g. DefaultConsistentHash) requires at least one owner for each segment, this method may add one or more owners for that segment. Since the data in that segment was lost, the new consistent hash can still be used without transferring state.

      Specified by:
      updateMembers in interface ConsistentHashFactory<ReplicatedConsistentHash>
      Parameters:
      baseCH - An existing consistent hash instance, should not be null
      newMembers - A list of addresses representing the new cache members.
      actualCapacityFactors - The capacity factor of each member. Determines the relative capacity of each node compared to the others. The implementation may ignore this parameter. If null, all the members are assumed to have a capacity factor of 1.
      Returns:
      A new ConsistentHash instance, or baseCH if the existing instance does not need any changes.

    • rebalance

      public ReplicatedConsistentHash rebalance(ReplicatedConsistentHash baseCH)
      Description copied from interface: ConsistentHashFactory
      Create a new consistent hash instance, based on an existing instance, but balanced according to the implementation's rules.
      Specified by:
      rebalance in interface ConsistentHashFactory<ReplicatedConsistentHash>
      Parameters:
      baseCH - An existing consistent hash instance, should not be null
      Returns:
      A new ConsistentHash instance, or baseCH if the existing instance does not need any changes.

    • union

      public ReplicatedConsistentHash union(ReplicatedConsistentHash ch1, ReplicatedConsistentHash ch2)
      Description copied from interface: ConsistentHashFactory
      Creates a union of two compatible ConsistentHashes (use the same hashing function and have the same configuration parameters).

      The owners of a segment s in union(ch1, ch2) will include both the owners of s in ch1 and the owners of s in ch2, so a cache can switch from using union(ch1, ch2) to using ch2 without transferring any state.

      Specified by:
      union in interface ConsistentHashFactory<ReplicatedConsistentHash>