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

Class AllocationDeciders

java.lang.Object

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

org.elasticsearch.cluster.routing.allocation.decider.AllocationDeciders

public class AllocationDeciders
extends AllocationDecider

A composite AllocationDecider combining the "decision" of multiple AllocationDecider implementations into a single allocation decision.

Constructor Summary

Constructors

Constructor	Description
AllocationDeciders(Collection<AllocationDecider> allocations)

Method Summary

Modifier and Type	Method	Description
Decision	canAllocate(IndexMetadata indexMetadata, RoutingNode node, RoutingAllocation allocation)	Returns a Decision whether the given shard routing can be allocated at all at this state of the RoutingAllocation.
Decision	canAllocate(ShardRouting shardRouting, RoutingAllocation allocation)	Returns a Decision whether the given shard routing can be allocated at all at this state of the RoutingAllocation.
Decision	canAllocate(ShardRouting shardRouting, RoutingNode node, RoutingAllocation allocation)	Returns a Decision whether the given shard routing can be allocated on the given node.
Decision	canAllocateReplicaWhenThereIsRetentionLease(ShardRouting shardRouting, RoutingNode node, RoutingAllocation allocation)	Returns a Decision whether the given replica shard can be allocated to the given node when there is an existing retention lease already existing on the node (meaning it has been allocated there previously) This method does not actually check whether there is a retention lease, that is the responsibility of the caller.
Decision	canForceAllocateDuringReplace(ShardRouting shardRouting, RoutingNode node, RoutingAllocation allocation)	Returns a Decision whether the given shard can be forced to the given node in the event that the shard's source node is being replaced.
Decision	canForceAllocatePrimary(ShardRouting shardRouting, RoutingNode node, RoutingAllocation allocation)	Returns a Decision whether the given primary shard can be forcibly allocated on the given node.
Decision	canRebalance(RoutingAllocation allocation)	Returns a Decision whether the cluster can execute re-balanced operations at all.
Decision	canRebalance(ShardRouting shardRouting, RoutingAllocation allocation)	Returns a Decision whether the given shard routing can be re-balanced to the given allocation.
Decision	canRemain(ShardRouting shardRouting, RoutingNode node, RoutingAllocation allocation)	Returns a Decision whether the given shard routing can be remain on the given node.
Decision	shouldAutoExpandToNode(IndexMetadata indexMetadata, DiscoveryNode node, RoutingAllocation allocation)	Returns a Decision whether shards of the given index should be auto-expanded to this node at this state of the RoutingAllocation.

Methods inherited from class java.lang.Object

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

Constructor Details

AllocationDeciders

public AllocationDeciders(Collection<AllocationDecider> allocations)

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

canAllocate

public Decision canAllocate(ShardRouting shardRouting,
 RoutingNode node,
 RoutingAllocation allocation)

Description copied from class: AllocationDecider

Returns a Decision whether the given shard routing can be allocated on the given node. The default is Decision.ALWAYS.

Overrides:

canAllocate in class AllocationDecider

canRemain

public Decision canRemain(ShardRouting shardRouting,
 RoutingNode node,
 RoutingAllocation allocation)

Description copied from class: AllocationDecider

Returns a Decision whether the given shard routing can be remain on the given node. The default is Decision.ALWAYS.

Overrides:

canRemain in class AllocationDecider

canAllocate

public Decision canAllocate(IndexMetadata indexMetadata,
 RoutingNode node,
 RoutingAllocation allocation)

Description copied from class: AllocationDecider

Returns a Decision whether the given shard routing can be allocated at all at this state of the RoutingAllocation. The default is Decision.ALWAYS.

Overrides:

canAllocate in class AllocationDecider

shouldAutoExpandToNode

public Decision shouldAutoExpandToNode(IndexMetadata indexMetadata,
 DiscoveryNode node,
 RoutingAllocation allocation)

Description copied from class: AllocationDecider

Returns a Decision whether shards of the given index should be auto-expanded to this node at this state of the RoutingAllocation. The default is Decision.ALWAYS.

Overrides:

shouldAutoExpandToNode in class AllocationDecider

canAllocate

public Decision canAllocate(ShardRouting shardRouting,
 RoutingAllocation allocation)

Description copied from class: AllocationDecider

Returns a Decision whether the given shard routing can be allocated at all at this state of the RoutingAllocation. The default is Decision.ALWAYS.

Overrides:

canAllocate in class AllocationDecider

canRebalance

public Decision canRebalance(RoutingAllocation allocation)

Description copied from class: AllocationDecider

Returns a Decision whether the cluster can execute re-balanced operations at all. Decision.ALWAYS.

Overrides:

canRebalance in class AllocationDecider

canForceAllocatePrimary

public Decision canForceAllocatePrimary(ShardRouting shardRouting,
 RoutingNode node,
 RoutingAllocation allocation)

Description copied from class: AllocationDecider

Returns a Decision whether the given primary shard can be forcibly allocated on the given node. This method should only be called for unassigned primary shards where the node has a shard copy on disk. Note: all implementations that override this behavior should take into account the results of AllocationDecider.canAllocate(ShardRouting, RoutingNode, RoutingAllocation) before making a decision on force allocation, because force allocation should only be considered if all deciders return Decision.NO.

Overrides:

canForceAllocatePrimary in class AllocationDecider

canForceAllocateDuringReplace

public Decision canForceAllocateDuringReplace(ShardRouting shardRouting,
 RoutingNode node,
 RoutingAllocation allocation)

Description copied from class: AllocationDecider

Returns a Decision whether the given shard can be forced to the given node in the event that the shard's source node is being replaced. This allows nodes using a replace-type node shutdown to override certain deciders in the interest of moving the shard away from a node that *must* be removed. It defaults to returning "YES" and must be overridden by deciders that opt-out to having their other NO decisions *not* overridden while vacating. The caller is responsible for first checking: - that a replacement is ongoing - the shard routing's current node is the source of the replacement

Overrides:

canForceAllocateDuringReplace in class AllocationDecider

canAllocateReplicaWhenThereIsRetentionLease

public Decision canAllocateReplicaWhenThereIsRetentionLease(ShardRouting shardRouting,
 RoutingNode node,
 RoutingAllocation allocation)

Description copied from class: AllocationDecider

Returns a Decision whether the given replica shard can be allocated to the given node when there is an existing retention lease already existing on the node (meaning it has been allocated there previously) This method does not actually check whether there is a retention lease, that is the responsibility of the caller. It defaults to the same value as canAllocate.

Overrides:

canAllocateReplicaWhenThereIsRetentionLease in class AllocationDecider