Class HashConfiguration

java.lang.Object

org.infinispan.commons.configuration.attributes.ConfigurationElement<HashConfiguration>

org.infinispan.configuration.cache.HashConfiguration

All Implemented Interfaces:

Matchable<HashConfiguration>, Updatable<HashConfiguration>

public class HashConfiguration
extends ConfigurationElement<HashConfiguration>

Allows fine-tuning of rehashing characteristics. Must be used only with 'distributed' cache mode.

Author:

pmuir

Field Summary

Fields

Modifier and Type	Field	Description
static final AttributeDefinition<Float>	CAPACITY_FACTOR
static final AttributeDefinition<KeyPartitioner>	KEY_PARTITIONER
static final AttributeDefinition<Integer>	NUM_OWNERS
static final AttributeDefinition<Integer>	NUM_SEGMENTS

Fields inherited from class org.infinispan.commons.configuration.attributes.ConfigurationElement

attributes, CHILDLESS, children, element, repeated

Method Summary

Modifier and Type	Method	Description
float	capacityFactor()	Controls the proportion of entries that will reside on the local node, compared to the other nodes in the cluster.
GroupsConfiguration	groups()	Configuration for various grouper definitions.
KeyPartitioner	keyPartitioner()
int	numOwners()	Number of cluster-wide replicas for each cache entry.
int	numSegments()	Controls the total number of hash space segments (per cluster).

Methods inherited from class org.infinispan.commons.configuration.attributes.ConfigurationElement

attributes, child, children, children, elementName, equals, findAttribute, hashCode, isModified, list, matches, toString, update, validateUpdate, write

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Details

NUM_OWNERS

public static final AttributeDefinition<Integer> NUM_OWNERS

NUM_SEGMENTS

public static final AttributeDefinition<Integer> NUM_SEGMENTS

CAPACITY_FACTOR

public static final AttributeDefinition<Float> CAPACITY_FACTOR

KEY_PARTITIONER

public static final AttributeDefinition<KeyPartitioner> KEY_PARTITIONER

Method Details

numOwners

public int numOwners()

Number of cluster-wide replicas for each cache entry.

numSegments

public int numSegments()

Controls the total number of hash space segments (per cluster).

A hash space segment is the granularity for key distribution in the cluster: a node can own (or primary-own) one or more full segments, but not a fraction of a segment. As such, very small numSegments values (< 10 segments per node) will make the distribution of keys between nodes more uneven.

The recommended value is 20 * the expected cluster size.

Note: The value returned by ConsistentHash.getNumSegments() may be different, e.g. rounded up to a power of 2.

capacityFactor

public float capacityFactor()

Controls the proportion of entries that will reside on the local node, compared to the other nodes in the cluster. This is just a suggestion, there is no guarantee that a node with a capacity factor of 2 will have twice as many entries as a node with a capacity factor of 1.

keyPartitioner

public KeyPartitioner keyPartitioner()

groups

public GroupsConfiguration groups()

Configuration for various grouper definitions. See the user guide for more information.