Package org.elasticsearch.gateway

Class ReplicaShardAllocator

java.lang.Object

org.elasticsearch.gateway.BaseGatewayShardAllocator

org.elasticsearch.gateway.ReplicaShardAllocator

public abstract class ReplicaShardAllocator
extends BaseGatewayShardAllocator

Field Summary

Fields inherited from class org.elasticsearch.gateway.BaseGatewayShardAllocator

logger

Constructor Summary

Constructors

Constructor	Description
ReplicaShardAllocator()

Method Summary

Modifier and Type	Method	Description
static Tuple<Decision,Map<String,NodeAllocationResult>>	canBeAllocatedToAtLeastOneNode(ShardRouting shard, RoutingAllocation allocation)	Determines if the shard can be allocated on at least one node based on the allocation deciders.
static AllocateUnassignedDecision	delayedDecision(ShardRouting unassignedShard, RoutingAllocation allocation, org.apache.logging.log4j.Logger logger, List<NodeAllocationResult> nodeDecisions)	Return a delayed decision, filling in the right amount of remaining time if decisions are debugged/explained.
protected abstract AsyncShardFetch.FetchResult<TransportNodesListShardStoreMetadata.NodeStoreFilesMetadata>	fetchData(ShardRouting shard, RoutingAllocation allocation)
protected abstract boolean	hasInitiatedFetching(ShardRouting shard)	Returns a boolean indicating whether fetching shard data has been triggered at any point for the given shard.
AllocateUnassignedDecision	makeAllocationDecision(ShardRouting unassignedShard, RoutingAllocation allocation, org.apache.logging.log4j.Logger logger)	Make a decision on the allocation of an unassigned shard.
void	processExistingRecoveries(RoutingAllocation allocation)	Process existing recoveries of replicas and see if we need to cancel them if we find a better match.

Methods inherited from class org.elasticsearch.gateway.BaseGatewayShardAllocator

allocateUnassigned, buildDecisionsForAllNodes, getExpectedShardSize

Methods inherited from class java.lang.Object

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

Constructor Details

ReplicaShardAllocator

public ReplicaShardAllocator()

Method Details

processExistingRecoveries

public void processExistingRecoveries(RoutingAllocation allocation)

Process existing recoveries of replicas and see if we need to cancel them if we find a better match. Today, a better match is one that can perform a no-op recovery while the previous recovery has to copy segment files.

makeAllocationDecision

public AllocateUnassignedDecision makeAllocationDecision(ShardRouting unassignedShard,
 RoutingAllocation allocation,
 org.apache.logging.log4j.Logger logger)

Description copied from class: BaseGatewayShardAllocator

Make a decision on the allocation of an unassigned shard. This method is used by BaseGatewayShardAllocator.allocateUnassigned(ShardRouting, RoutingAllocation, ExistingShardsAllocator.UnassignedAllocationHandler) to make decisions about whether or not the shard can be allocated by this allocator and if so, to which node it will be allocated.

Specified by:

makeAllocationDecision in class BaseGatewayShardAllocator

Parameters:

unassignedShard - the unassigned shard to allocate

allocation - the current routing state

logger - the logger

Returns:

an AllocateUnassignedDecision with the final decision of whether to allocate and details of the decision

delayedDecision

public static AllocateUnassignedDecision delayedDecision(ShardRouting unassignedShard,
 RoutingAllocation allocation,
 org.apache.logging.log4j.Logger logger,
 List<NodeAllocationResult> nodeDecisions)

Return a delayed decision, filling in the right amount of remaining time if decisions are debugged/explained.

canBeAllocatedToAtLeastOneNode

public static Tuple<Decision,Map<String,NodeAllocationResult>> canBeAllocatedToAtLeastOneNode(ShardRouting shard,
 RoutingAllocation allocation)

Determines if the shard can be allocated on at least one node based on the allocation deciders. Returns the best allocation decision for allocating the shard on any node (i.e. YES if at least one node decided YES, THROTTLE if at least one node decided THROTTLE, and NO if none of the nodes decided YES or THROTTLE). If in explain mode, also returns the node-level explanations as the second element in the returned tuple.

fetchData

protected abstract AsyncShardFetch.FetchResult<TransportNodesListShardStoreMetadata.NodeStoreFilesMetadata> fetchData(ShardRouting shard,
 RoutingAllocation allocation)

hasInitiatedFetching

protected abstract boolean hasInitiatedFetching(ShardRouting shard)

Returns a boolean indicating whether fetching shard data has been triggered at any point for the given shard.