Module org.elasticsearch.server

Package org.elasticsearch.cluster.routing.allocation.decider

Class ConcurrentRebalanceAllocationDecider

java.lang.Object

org.elasticsearch.cluster.routing.allocation.decider.AllocationDecider

org.elasticsearch.cluster.routing.allocation.decider.ConcurrentRebalanceAllocationDecider

public class ConcurrentRebalanceAllocationDecider
extends AllocationDecider

Similar to the ClusterRebalanceAllocationDecider this AllocationDecider controls the number of currently in-progress re-balance (shard relocation) operations and restricts node allocations if the configured threshold is reached. Frozen and non-frozen shards are considered separately. The default number of concurrent rebalance operations is set to 2 for non-frozen shards. For frozen shards, the default is the same setting as non-frozen shards, until set explicitly.

Re-balance operations can be controlled in real-time via the cluster update API using cluster.routing.allocation.cluster_concurrent_rebalance and cluster.routing.allocation.cluster_concurrent_frozen_rebalance. Iff either setting is set to -1 the number of concurrent re-balance operations within the setting's category (frozen or non-frozen) are unlimited.

Field Summary

Fields

Modifier and Type	Field	Description
static final Setting<Integer>	CLUSTER_ROUTING_ALLOCATION_CLUSTER_CONCURRENT_FROZEN_REBALANCE_SETTING	Same as cluster_concurrent_rebalance, but applies separately to frozen tier shards Defaults to the same value as normal concurrent rebalance, if unspecified
static final Setting<Integer>	CLUSTER_ROUTING_ALLOCATION_CLUSTER_CONCURRENT_REBALANCE_SETTING
static final String	NAME

Constructor Summary

Constructors

Constructor	Description
ConcurrentRebalanceAllocationDecider(ClusterSettings clusterSettings)

Method Summary

Modifier and Type	Method	Description
Decision	canRebalance(RoutingAllocation allocation)	We allow a limited number of concurrent shard relocations, per the cluster setting CLUSTER_ROUTING_ALLOCATION_CLUSTER_CONCURRENT_REBALANCE_SETTING.
Decision	canRebalance(ShardRouting shardRouting, RoutingAllocation allocation)	Returns a Decision whether the given shard routing can be re-balanced to the given allocation.

Methods inherited from class org.elasticsearch.cluster.routing.allocation.decider.AllocationDecider

canAllocate, canAllocate, canAllocate, canAllocateReplicaWhenThereIsRetentionLease, canForceAllocateDuringReplace, canForceAllocatePrimary, canRemain, getForcedInitialShardAllocationToNodes, shouldAutoExpandToNode

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

NAME

public static final String NAME

See Also:

• Constant Field Values

CLUSTER_ROUTING_ALLOCATION_CLUSTER_CONCURRENT_REBALANCE_SETTING

public static final Setting<Integer> CLUSTER_ROUTING_ALLOCATION_CLUSTER_CONCURRENT_REBALANCE_SETTING

CLUSTER_ROUTING_ALLOCATION_CLUSTER_CONCURRENT_FROZEN_REBALANCE_SETTING

public static final Setting<Integer> CLUSTER_ROUTING_ALLOCATION_CLUSTER_CONCURRENT_FROZEN_REBALANCE_SETTING

Same as cluster_concurrent_rebalance, but applies separately to frozen tier shards Defaults to the same value as normal concurrent rebalance, if unspecified

Constructor Details

ConcurrentRebalanceAllocationDecider

public ConcurrentRebalanceAllocationDecider(ClusterSettings clusterSettings)

Method Details

canRebalance

public Decision canRebalance(ShardRouting shardRouting,
 RoutingAllocation allocation)

Description copied from class: AllocationDecider

Returns a Decision whether the given shard routing can be re-balanced to the given allocation. The default is Decision.ALWAYS.

Overrides:

canRebalance in class AllocationDecider

canRebalance

public Decision canRebalance(RoutingAllocation allocation)

We allow a limited number of concurrent shard relocations, per the cluster setting CLUSTER_ROUTING_ALLOCATION_CLUSTER_CONCURRENT_REBALANCE_SETTING. Returns a Decision.THROTTLE decision if the limit is exceeded, otherwise returns Decision.YES.

Overrides:

canRebalance in class AllocationDecider

Returns:

Decision.ALWAYS is returned by default if not overridden.