com.hazelcast.map.impl.eviction

Class ExpirationManager

java.lang.Object

com.hazelcast.map.impl.eviction.ExpirationManager

All Implemented Interfaces:

OperationResponseHandler

public final class ExpirationManager
extends Object
implements OperationResponseHandler

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	sendExpiredKeysToBackups(RecordStore recordStore, boolean checkIfReachedBatch)
void	sendResponse(Operation op, Object response) Sends a response.
void	start()
void	stop()

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

start

public void start()

stop

public void stop()

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)