com.hazelcast.map.impl.eviction

Class ExpirationManager

java.lang.Object

com.hazelcast.map.impl.eviction.ExpirationManager

public final class ExpirationManager
extends Object

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.

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 int	DEFAULT_EXPIRATION_CLEANUP_PERCENTAGE
static int	DEFAULT_EXPIRATION_TASK_PERIOD_SECONDS
static int	DIFFERENCE_BETWEEN_TWO_SUBSEQUENT_PARTITION_CLEANUP_MILLIS
static String	SYS_PROP_EXPIRATION_CLEANUP_OPERATION_COUNT
static String	SYS_PROP_EXPIRATION_CLEANUP_PERCENTAGE
static String	SYS_PROP_EXPIRATION_TASK_PERIOD_SECONDS

Constructor Summary

Constructors

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

Method Summary

Modifier and Type	Method and Description
void	start()
void	stop()

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_EXPIRATION_TASK_PERIOD_SECONDS

public static final int DEFAULT_EXPIRATION_TASK_PERIOD_SECONDS

See Also:

Constant Field Values

DEFAULT_EXPIRATION_CLEANUP_PERCENTAGE

public static final int DEFAULT_EXPIRATION_CLEANUP_PERCENTAGE

See Also:

Constant Field Values

DIFFERENCE_BETWEEN_TWO_SUBSEQUENT_PARTITION_CLEANUP_MILLIS

public static final int DIFFERENCE_BETWEEN_TWO_SUBSEQUENT_PARTITION_CLEANUP_MILLIS

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Constant Field Values

SYS_PROP_EXPIRATION_CLEANUP_OPERATION_COUNT

public static final String SYS_PROP_EXPIRATION_CLEANUP_OPERATION_COUNT

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Constant Field Values

SYS_PROP_EXPIRATION_TASK_PERIOD_SECONDS

public static final String SYS_PROP_EXPIRATION_TASK_PERIOD_SECONDS

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Constant Field Values

SYS_PROP_EXPIRATION_CLEANUP_PERCENTAGE

public static final String SYS_PROP_EXPIRATION_CLEANUP_PERCENTAGE

See Also:

Constant Field Values

Constructor Detail

ExpirationManager

public ExpirationManager(PartitionContainer[] partitionContainers,
                         NodeEngine nodeEngine)

Method Detail

start

public void start()

stop

public void stop()