com.hazelcast.map.impl.eviction

Class ExpirationManager

java.lang.Object

com.hazelcast.map.impl.eviction.ExpirationManager

All Implemented Interfaces:

LifecycleListener, OperationResponseHandler, EventListener

public final class ExpirationManager
extends Object
implements OperationResponseHandler, LifecycleListener

This class is responsible for gradual cleanup of expired entries. For this purpose it uses a background task.

This background task can be accelerated or can be slowed down by using the system properties below:

• "hazelcast.internal.map.expiration.task.period.seconds": A new round is started after this period of seconds. Default value is 5 seconds. So every 5 seconds there will be a new round.
• "hazelcast.internal.map.expiration.cleanup.percentage": Scannable percentage of entries in a maps' partition in each round. Default percentage is 10%.
• "hazelcast.internal.map.expiration.cleanup.operation.count": Number of scannable partitions in each round. No default value exists. Dynamically calculated against partition-count or partition-thread-count.
• "hazelcast.internal.map.expiration.primary.drives_backup": Used to enable/disable management of backup expiration from primary. This can only be used with max idle seconds expiration.

These parameters can be set node-wide or system-wide

Node-wide setting example:

          Config config = new Config();
          config.setProperty(
          "hazelcast.internal.map.expiration.cleanup.operation.count", "3");
          Hazelcast.newHazelcastInstance(config);
      

System-wide setting example:

       System.setProperty(
       "hazelcast.internal.map.expiration.cleanup.operation.count", "3");
   

Since:

3.3

Field Summary

Fields

Modifier and Type	Field and Description
static HazelcastProperty	CLEANUP_OPERATION_COUNT
static HazelcastProperty	CLEANUP_PERCENTAGE
static int	DEFAULT_CLEANUP_PERCENTAGE
static boolean	DEFAULT_PRIMARY_DRIVES_BACKUP
static int	DEFAULT_TASK_PERIOD_SECONDS
static int	DIFFERENCE_BETWEEN_TWO_SUBSEQUENT_PARTITION_CLEANUP_MILLIS
static int	MAX_EXPIRED_KEY_COUNT_IN_BATCH
static HazelcastProperty	PRIMARY_DRIVES_BACKUP
static String	PROP_CLEANUP_OPERATION_COUNT
static String	PROP_CLEANUP_PERCENTAGE
static String	PROP_PRIMARY_DRIVES_BACKUP
static String	PROP_TASK_PERIOD_SECONDS
static HazelcastProperty	TASK_PERIOD_SECONDS

Constructor Summary

Constructors

Constructor and Description
ExpirationManager(PartitionContainer[] partitionContainers, NodeEngine nodeEngine)

Method Summary

Modifier and Type	Method and Description
boolean	canPrimaryDriveExpiration()
void	onClusterStateChange(ClusterState newState)
void	scheduleExpirationTask() Starts scheduling of the task that clears expired entries.
void	sendExpiredKeysToBackups(RecordStore recordStore, boolean checkIfReachedBatch)
void	sendResponse(Operation op, Object response) Sends a response.
void	stateChanged(LifecycleEvent event) Called when instance's state changes.

Methods inherited from class java.lang.Object

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

Field Detail

PROP_PRIMARY_DRIVES_BACKUP

public static final String PROP_PRIMARY_DRIVES_BACKUP

See Also:

Constant Field Values

PROP_TASK_PERIOD_SECONDS

public static final String PROP_TASK_PERIOD_SECONDS

See Also:

Constant Field Values

PROP_CLEANUP_PERCENTAGE

public static final String PROP_CLEANUP_PERCENTAGE

See Also:

Constant Field Values

PROP_CLEANUP_OPERATION_COUNT

public static final String PROP_CLEANUP_OPERATION_COUNT

See Also:

Constant Field Values

DEFAULT_PRIMARY_DRIVES_BACKUP

public static final boolean DEFAULT_PRIMARY_DRIVES_BACKUP

See Also:

Constant Field Values

DEFAULT_TASK_PERIOD_SECONDS

public static final int DEFAULT_TASK_PERIOD_SECONDS

See Also:

Constant Field Values

DEFAULT_CLEANUP_PERCENTAGE

public static final int DEFAULT_CLEANUP_PERCENTAGE

See Also:

Constant Field Values

MAX_EXPIRED_KEY_COUNT_IN_BATCH

public static final int MAX_EXPIRED_KEY_COUNT_IN_BATCH

See Also:

Constant Field Values

DIFFERENCE_BETWEEN_TWO_SUBSEQUENT_PARTITION_CLEANUP_MILLIS

public static final int DIFFERENCE_BETWEEN_TWO_SUBSEQUENT_PARTITION_CLEANUP_MILLIS

See Also:

Constant Field Values

PRIMARY_DRIVES_BACKUP

public static final HazelcastProperty PRIMARY_DRIVES_BACKUP

TASK_PERIOD_SECONDS

public static final HazelcastProperty TASK_PERIOD_SECONDS

CLEANUP_PERCENTAGE

public static final HazelcastProperty CLEANUP_PERCENTAGE

CLEANUP_OPERATION_COUNT

public static final HazelcastProperty CLEANUP_OPERATION_COUNT

Constructor Detail

ExpirationManager

public ExpirationManager(PartitionContainer[] partitionContainers,
                         NodeEngine nodeEngine)

Method Detail

scheduleExpirationTask

public void scheduleExpirationTask()

Starts scheduling of the task that clears expired entries. Calling this method multiple times has same effect.

stateChanged

public void stateChanged(LifecycleEvent event)

Description copied from interface: LifecycleListener

Called when instance's state changes. No blocking calls should be made in this method.

Specified by:

stateChanged in interface LifecycleListener

Parameters:

event - the Lifecycle event

onClusterStateChange

public void onClusterStateChange(ClusterState newState)

sendResponse

public void sendResponse(Operation op,
                         Object response)

Description copied from interface: OperationResponseHandler

Sends a response.

Specified by:

sendResponse in interface OperationResponseHandler

Parameters:

op - the operation that got executed.

response - the response of the operation that got executed.

canPrimaryDriveExpiration

public boolean canPrimaryDriveExpiration()

sendExpiredKeysToBackups

public void sendExpiredKeysToBackups(RecordStore recordStore,
                                     boolean checkIfReachedBatch)