Module org.elasticsearch.server

Package org.elasticsearch.snapshots

Class SnapshotShardsService

java.lang.Object

org.elasticsearch.common.component.AbstractLifecycleComponent

org.elasticsearch.snapshots.SnapshotShardsService

All Implemented Interfaces:

Closeable, AutoCloseable, ClusterStateListener, LifecycleComponent, Releasable, IndexEventListener

public class SnapshotShardsService
extends AbstractLifecycleComponent
implements ClusterStateListener, IndexEventListener

This service runs on data nodes and controls currently running shard snapshots on these nodes. It is responsible for starting and stopping shard level snapshots. See package level documentation of org.elasticsearch.snapshots for details.

Field Summary

Fields inherited from class org.elasticsearch.common.component.AbstractLifecycleComponent

lifecycle

Constructor Summary

Constructors

Constructor	Description
SnapshotShardsService(Settings settings, ClusterService clusterService, RepositoriesService repositoriesService, TransportService transportService, IndicesService indicesService)

Method Summary

Modifier and Type	Method	Description
void	beforeIndexShardClosed(ShardId shardId, IndexShard indexShard, Settings indexSettings)	Called before the index shard gets closed.
void	clusterChanged(ClusterChangedEvent event)	Called when cluster state changes.
Map<ShardId,IndexShardSnapshotStatus>	currentSnapshotShards(Snapshot snapshot)	Returns status of shards that are snapshotted on the node and belong to the given snapshot
protected void	doClose()
protected void	doStart()
protected void	doStop()
static String	getShardStateId(IndexShard indexShard, org.apache.lucene.index.IndexCommit snapshotIndexCommit)	Generates an identifier from the current state of a shard that can be used to detect whether a shard's contents have changed between two snapshots.

Methods inherited from class org.elasticsearch.common.component.AbstractLifecycleComponent

addLifecycleListener, close, lifecycleState, start, stop

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.elasticsearch.index.shard.IndexEventListener

afterFilesRestoredFromRepository, afterIndexCreated, afterIndexRemoved, afterIndexShardClosed, afterIndexShardCreated, afterIndexShardDeleted, afterIndexShardStarted, beforeIndexAddedToCluster, beforeIndexCreated, beforeIndexRemoved, beforeIndexShardCreated, beforeIndexShardDeleted, beforeIndexShardRecovery, indexShardStateChanged, onStoreClosed, onStoreCreated, shardRoutingChanged

Constructor Details

SnapshotShardsService

public SnapshotShardsService(Settings settings,
 ClusterService clusterService,
 RepositoriesService repositoriesService,
 TransportService transportService,
 IndicesService indicesService)

Method Details

doStart

protected void doStart()

Specified by:

doStart in class AbstractLifecycleComponent

doStop

protected void doStop()

Specified by:

doStop in class AbstractLifecycleComponent

doClose

protected void doClose()

Specified by:

doClose in class AbstractLifecycleComponent

clusterChanged

public void clusterChanged(ClusterChangedEvent event)

Description copied from interface: ClusterStateListener

Called when cluster state changes.

Cluster states are applied one-by-one which means they can be a performance bottleneck. Implementations of this method should therefore be fast, so please consider forking work into the background rather than doing everything inline.

Specified by:

clusterChanged in interface ClusterStateListener

beforeIndexShardClosed

public void beforeIndexShardClosed(ShardId shardId,
 @Nullable
 IndexShard indexShard,
 Settings indexSettings)

Description copied from interface: IndexEventListener

Called before the index shard gets closed.

Specified by:

beforeIndexShardClosed in interface IndexEventListener

indexShard - The index shard

currentSnapshotShards

public Map<ShardId,IndexShardSnapshotStatus> currentSnapshotShards(Snapshot snapshot)

Returns status of shards that are snapshotted on the node and belong to the given snapshot

This method is executed on data node

Parameters:

snapshot - snapshot

Returns:

map of shard id to snapshot status

getShardStateId

@Nullable
public static String getShardStateId(IndexShard indexShard,
 org.apache.lucene.index.IndexCommit snapshotIndexCommit)
                              throws IOException

Generates an identifier from the current state of a shard that can be used to detect whether a shard's contents have changed between two snapshots. A shard is assumed to have unchanged contents if its global- and local checkpoint are equal, its maximum sequence number has not changed and its history- and force-merge-uuid have not changed. The method returns null if global and local checkpoint are different for a shard since no safe unique shard state id can be used in this case because of the possibility of a primary failover leading to different shard content for the same sequence number on a subsequent snapshot.

Parameters:

indexShard - Shard

snapshotIndexCommit - IndexCommit for shard

Returns:

shard state id or null if none can be used

Throws:

IOException