com.hazelcast.spi

Interface FragmentedMigrationAwareService

All Superinterfaces:

MigrationAwareService

All Known Implementing Classes:

LockServiceImpl

public interface FragmentedMigrationAwareService
extends MigrationAwareService

FragmentedMigrationAwareService is an extension to the MigrationAwareService which allows migration/replication of partition replicas in smaller fragments.

Each replica fragment is distinguished by a ServiceNamespace, all replica data belonging to a specific namespace will be transferred in the same packet.

Both backup and backup aware operations created by FragmentedMigrationAwareService must implement ServiceNamespaceAware interface and must know their related ServiceNamespaces.

Fragmented migration can be enabled/disabled using configuration property GroupProperty.PARTITION_FRAGMENTED_MIGRATION_ENABLED. Anti-entropy system which detects and completes inconsistent backup replicas, always uses fragmented replication for services having support.

Since:

3.9

See Also:

MigrationAwareService, ServiceNamespace, ServiceNamespaceAware

Method Summary

Modifier and Type	Method and Description
Collection<ServiceNamespace>	getAllServiceNamespaces(PartitionReplicationEvent event) Returns all known namespaces for given replication event.
boolean	isKnownServiceNamespace(ServiceNamespace namespace) Returns true if namespace is known by this service, false otherwise
Operation	prepareReplicationOperation(PartitionReplicationEvent event, Collection<ServiceNamespace> namespaces) Returns an operation to replicate service data and/or state for a specific partition replica and namespaces on another cluster member.

Methods inherited from interface com.hazelcast.spi.MigrationAwareService

beforeMigration, commitMigration, prepareReplicationOperation, rollbackMigration

Method Detail

getAllServiceNamespaces

Collection<ServiceNamespace> getAllServiceNamespaces(PartitionReplicationEvent event)

Returns all known namespaces for given replication event.

Parameters:

event - replication event

Returns:

all known service namespaces for the replication

isKnownServiceNamespace

boolean isKnownServiceNamespace(ServiceNamespace namespace)

Returns true if namespace is known by this service, false otherwise

Parameters:

namespace - namespace

Returns:

true if namespace is known by this service, false otherwise

prepareReplicationOperation

Operation prepareReplicationOperation(PartitionReplicationEvent event,
                                      Collection<ServiceNamespace> namespaces)

Returns an operation to replicate service data and/or state for a specific partition replica and namespaces on another cluster member. This method is very similar to MigrationAwareService.prepareReplicationOperation(PartitionReplicationEvent), instead of copying whole partition replica, allows copying only some portion of replica, specified by given namespaces.

This method will be called on source member whenever partitioning system requires to copy/replicate a partition replica. Returned operation will be executed on destination member. If operation fails by throwing exception, migration process will fail and will be rolled back.

Returning null is allowed and means service does not have anything to replicate.

Parameters:

event - replication event

namespaces - replica fragment namespaces to replicate

Returns:

replication operation or null if nothing will be replicated

See Also:

MigrationAwareService.prepareReplicationOperation(PartitionReplicationEvent)