org.elasticsearch.index.seqno

Class SequenceNumbersService

java.lang.Object

org.elasticsearch.index.shard.AbstractIndexShardComponent

org.elasticsearch.index.seqno.SequenceNumbersService

All Implemented Interfaces:

IndexShardComponent

public class SequenceNumbersService
extends AbstractIndexShardComponent

Encapsulates the local and global checkpoints into a single service for use as a shard component.

Field Summary

Fields

Modifier and Type	Field and Description
static long	NO_OPS_PERFORMED Represents no operations have been performed on the shard.
static long	UNASSIGNED_SEQ_NO Represents an unassigned sequence number (e.g., can be used on primary operations before they are executed).

Fields inherited from class org.elasticsearch.index.shard.AbstractIndexShardComponent

deprecationLogger, indexSettings, logger, shardId

Constructor Summary

Constructors

Constructor and Description
SequenceNumbersService(ShardId shardId, IndexSettings indexSettings, long maxSeqNo, long localCheckpoint, long globalCheckpoint) Initialize the sequence number service.

Method Summary

Modifier and Type	Method and Description
long	generateSeqNo() Issue the next sequence number.
long	getGlobalCheckpoint() Returns the global checkpoint for the shard.
long	getLocalCheckpoint() Returns the local checkpoint for the shard.
long	getMaxSeqNo() The maximum sequence number issued so far.
void	markAllocationIdAsInSync(java.lang.String allocationId, long localCheckpoint) Marks the shard with the provided allocation ID as in-sync with the primary shard.
void	markSeqNoAsCompleted(long seqNo) Marks the processing of the provided sequence number as completed as updates the checkpoint if possible.
boolean	pendingInSync() Check if there are any recoveries pending in-sync.
SeqNoStats	stats() The current sequence number stats.
void	updateAllocationIdsFromMaster(java.util.Set<java.lang.String> activeAllocationIds, java.util.Set<java.lang.String> initializingAllocationIds) Notifies the service of the current allocation IDs in the cluster state.
void	updateGlobalCheckpointOnReplica(long globalCheckpoint) Updates the global checkpoint on a replica shard after it has been updated by the primary.
void	updateLocalCheckpointForShard(java.lang.String allocationId, long checkpoint) Notifies the service to update the local checkpoint for the shard with the provided allocation ID.
void	waitForOpsToComplete(long seqNo) Waits for all operations up to the provided sequence number to complete.

Methods inherited from class org.elasticsearch.index.shard.AbstractIndexShardComponent

indexSettings, nodeName, shardId

Methods inherited from class java.lang.Object

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

Field Detail

UNASSIGNED_SEQ_NO

public static final long UNASSIGNED_SEQ_NO

Represents an unassigned sequence number (e.g., can be used on primary operations before they are executed).

See Also:

Constant Field Values

NO_OPS_PERFORMED

public static final long NO_OPS_PERFORMED

Represents no operations have been performed on the shard.

See Also:

Constant Field Values

Constructor Detail

SequenceNumbersService

public SequenceNumbersService(ShardId shardId,
                              IndexSettings indexSettings,
                              long maxSeqNo,
                              long localCheckpoint,
                              long globalCheckpoint)

Initialize the sequence number service. The maxSeqNo should be set to the last sequence number assigned by this shard, or NO_OPS_PERFORMED, localCheckpoint should be set to the last known local checkpoint for this shard, or NO_OPS_PERFORMED, and globalCheckpoint should be set to the last known global checkpoint for this shard, or UNASSIGNED_SEQ_NO.

Parameters:

shardId - the shard this service is providing tracking local checkpoints for

indexSettings - the index settings

maxSeqNo - the last sequence number assigned by this shard, or NO_OPS_PERFORMED

localCheckpoint - the last known local checkpoint for this shard, or NO_OPS_PERFORMED

globalCheckpoint - the last known global checkpoint for this shard, or UNASSIGNED_SEQ_NO

Method Detail

generateSeqNo

public long generateSeqNo()

Issue the next sequence number. Note that you must call markSeqNoAsCompleted(long) after the operation for which the issued sequence number completes (whether or not the operation completes successfully).

Returns:

the next assigned sequence number

getMaxSeqNo

public long getMaxSeqNo()

The maximum sequence number issued so far. See LocalCheckpointTracker.getMaxSeqNo() for additional details.

Returns:

the maximum sequence number

waitForOpsToComplete

public void waitForOpsToComplete(long seqNo)
                          throws java.lang.InterruptedException

Waits for all operations up to the provided sequence number to complete.

Parameters:

seqNo - the sequence number that the checkpoint must advance to before this method returns

Throws:

java.lang.InterruptedException - if the thread was interrupted while blocking on the condition

markSeqNoAsCompleted

public void markSeqNoAsCompleted(long seqNo)

Marks the processing of the provided sequence number as completed as updates the checkpoint if possible. See LocalCheckpointTracker.markSeqNoAsCompleted(long) for additional details.

Parameters:

seqNo - the sequence number to mark as completed

stats

public SeqNoStats stats()

The current sequence number stats.

Returns:

stats encapsulating the maximum sequence number, the local checkpoint and the global checkpoint

updateLocalCheckpointForShard

public void updateLocalCheckpointForShard(java.lang.String allocationId,
                                          long checkpoint)

Notifies the service to update the local checkpoint for the shard with the provided allocation ID. See GlobalCheckpointTracker.updateLocalCheckpoint(String, long) for details.

Parameters:

allocationId - the allocation ID of the shard to update the local checkpoint for

checkpoint - the local checkpoint for the shard

markAllocationIdAsInSync

public void markAllocationIdAsInSync(java.lang.String allocationId,
                                     long localCheckpoint)
                              throws java.lang.InterruptedException

Marks the shard with the provided allocation ID as in-sync with the primary shard. See GlobalCheckpointTracker.markAllocationIdAsInSync(String, long) for additional details.

Parameters:

allocationId - the allocation ID of the shard to mark as in-sync

localCheckpoint - the current local checkpoint on the shard

Throws:

java.lang.InterruptedException

getLocalCheckpoint

public long getLocalCheckpoint()

Returns the local checkpoint for the shard.

Returns:

the local checkpoint

getGlobalCheckpoint

public long getGlobalCheckpoint()

Returns the global checkpoint for the shard.

Returns:

the global checkpoint

updateGlobalCheckpointOnReplica

public void updateGlobalCheckpointOnReplica(long globalCheckpoint)

Updates the global checkpoint on a replica shard after it has been updated by the primary.

Parameters:

globalCheckpoint - the global checkpoint

updateAllocationIdsFromMaster

public void updateAllocationIdsFromMaster(java.util.Set<java.lang.String> activeAllocationIds,
                                          java.util.Set<java.lang.String> initializingAllocationIds)

Notifies the service of the current allocation IDs in the cluster state. See GlobalCheckpointTracker.updateAllocationIdsFromMaster(Set, Set) for details.

Parameters:

activeAllocationIds - the allocation IDs of the currently active shard copies

initializingAllocationIds - the allocation IDs of the currently initializing shard copies

pendingInSync

public boolean pendingInSync()

Check if there are any recoveries pending in-sync.

Returns:

true if there is at least one shard pending in-sync, otherwise false