Interface ICacheAffinity
Provides affinity information to detect which node is primary and which nodes are backups for a partitioned cache. You can get an instance of this interface by calling GetAffinity(String) method.
Mapping of a key to a node is a three-step operation. First step will get an affinity key for
given key using CacheAffinityKeyMapper
. If mapper is not specified, the original key
will be used. Second step will map affinity key to partition using
CacheAffinityFunction.partition(Object)
method. Third step will map obtained partition
to nodes for current grid topology version.
Interface provides various mapKeysToNodes(...)
methods which provide node affinity mapping
for given keys. All mapKeysToNodes(...)
methods are not transactional and will not enlist
keys into ongoing transaction.
All members are thread-safe and may be used concurrently from multiple threads.
Namespace: Apache.Ignite.Core.Cache
Assembly: Apache.Ignite.Core.dll
Syntax
public interface ICacheAffinity
Properties
Partitions
Gets number of partitions in cache according to configured affinity function.
Declaration
int Partitions { get; }
Property Value
Type | Description |
---|---|
System.Int32 | Number of cache partitions. |
Methods
GetAffinityKey<TK, TR>(TK)
Maps passed in key to a key which will be used for node affinity.
Declaration
TR GetAffinityKey<TK, TR>(TK key)
Parameters
Type | Name | Description |
---|---|---|
TK | key | Key to map. |
Returns
Type | Description |
---|---|
TR | Key to be used for node-to-affinity mapping (may be the same key as passed in). |
Type Parameters
Name | Description |
---|---|
TK | |
TR |
GetAllPartitions(IClusterNode)
Gets partition ids for which nodes of the given projection has ownership (either primary or backup).
Declaration
int[] GetAllPartitions(IClusterNode n)
Parameters
Type | Name | Description |
---|---|---|
IClusterNode | n | Node. |
Returns
Type | Description |
---|---|
System.Int32[] | Partition ids for which given projection has ownership. |
GetBackupPartitions(IClusterNode)
Gets partition ids for which nodes of the given projection has backup ownership.
Declaration
int[] GetBackupPartitions(IClusterNode n)
Parameters
Type | Name | Description |
---|---|---|
IClusterNode | n | Node. |
Returns
Type | Description |
---|---|
System.Int32[] | Partition ids for which given projection has backup ownership. |
GetPartition<TK>(TK)
Gets partition id for the given key.
Declaration
int GetPartition<TK>(TK key)
Parameters
Type | Name | Description |
---|---|---|
TK | key | Key to get partition id for. |
Returns
Type | Description |
---|---|
System.Int32 | Partition id. |
Type Parameters
Name | Description |
---|---|
TK |
GetPrimaryPartitions(IClusterNode)
Gets partition ids for which nodes of the given projection has primary ownership.
Declaration
int[] GetPrimaryPartitions(IClusterNode n)
Parameters
Type | Name | Description |
---|---|---|
IClusterNode | n | Node. |
Returns
Type | Description |
---|---|
System.Int32[] | Partition ids for which given projection has primary ownership. |
IsBackup<TK>(IClusterNode, TK)
Returns 'true' if given node is the backup node for given key.
Declaration
bool IsBackup<TK>(IClusterNode n, TK key)
Parameters
Type | Name | Description |
---|---|---|
IClusterNode | n | Node. |
TK | key | Key. |
Returns
Type | Description |
---|---|
System.Boolean | 'True' if given node is the backup node for given key. |
Type Parameters
Name | Description |
---|---|
TK |
IsPrimary<TK>(IClusterNode, TK)
Returns 'true' if given node is the primary node for given key.
Declaration
bool IsPrimary<TK>(IClusterNode n, TK key)
Parameters
Type | Name | Description |
---|---|---|
IClusterNode | n | Node. |
TK | key | Key. |
Returns
Type | Description |
---|---|
System.Boolean | 'True' if given node is the primary node for given key. |
Type Parameters
Name | Description |
---|---|
TK |
IsPrimaryOrBackup<TK>(IClusterNode, TK)
Returns 'true' if given node is either primary or backup node for given key.
Declaration
bool IsPrimaryOrBackup<TK>(IClusterNode n, TK key)
Parameters
Type | Name | Description |
---|---|---|
IClusterNode | n | Node. |
TK | key | Key. |
Returns
Type | Description |
---|---|
System.Boolean | 'True' if given node is either primary or backup node for given key. |
Type Parameters
Name | Description |
---|---|
TK |
MapKeysToNodes<TK>(IEnumerable<TK>)
This method provides ability to detect which keys are mapped to which nodes. Use it to determine which nodes are storing which keys prior to sending jobs that access these keys.
Declaration
IDictionary<IClusterNode, IList<TK>> MapKeysToNodes<TK>(IEnumerable<TK> keys)
Parameters
Type | Name | Description |
---|---|---|
IEnumerable<TK> | keys | Keys to map to nodes. |
Returns
Type | Description |
---|---|
IDictionary<IClusterNode, IList<TK>> | Map of nodes to keys or empty map if there are no alive nodes for this cache. |
Type Parameters
Name | Description |
---|---|
TK |
MapKeyToNode<TK>(TK)
This method provides ability to detect to which primary node the given key is mapped. Use it to determine which nodes are storing which keys prior to sending jobs that access these keys.
Declaration
IClusterNode MapKeyToNode<TK>(TK key)
Parameters
Type | Name | Description |
---|---|---|
TK | key | Key to map to a node. |
Returns
Type | Description |
---|---|
IClusterNode | Primary node for the key or null if there are no alive nodes for this cache. |
Type Parameters
Name | Description |
---|---|
TK |
MapKeyToPrimaryAndBackups<TK>(TK)
Gets primary and backup nodes for the key. Note that primary node is always first in the returned collection.
Declaration
IList<IClusterNode> MapKeyToPrimaryAndBackups<TK>(TK key)
Parameters
Type | Name | Description |
---|---|---|
TK | key |
Returns
Type | Description |
---|---|
IList<IClusterNode> |
Type Parameters
Name | Description |
---|---|
TK |
MapPartitionsToNodes(IEnumerable<Int32>)
Gets primary nodes for the given partitions.
Declaration
IDictionary<int, IClusterNode> MapPartitionsToNodes(IEnumerable<int> parts)
Parameters
Type | Name | Description |
---|---|---|
IEnumerable<System.Int32> | parts | Partition ids. |
Returns
Type | Description |
---|---|
IDictionary<System.Int32, IClusterNode> | Mapping of given partitions to their primary nodes. |
MapPartitionToNode(Int32)
Gets primary node for the given partition.
Declaration
IClusterNode MapPartitionToNode(int part)
Parameters
Type | Name | Description |
---|---|---|
System.Int32 | part | Partition id. |
Returns
Type | Description |
---|---|
IClusterNode | Primary node for the given partition. |
MapPartitionToPrimaryAndBackups(Int32)
Gets primary and backup nodes for partition. Note that primary node is always first in the returned collection.
Declaration
IList<IClusterNode> MapPartitionToPrimaryAndBackups(int part)
Parameters
Type | Name | Description |
---|---|---|
System.Int32 | part | Partition to get affinity nodes for. |
Returns
Type | Description |
---|---|
IList<IClusterNode> | Collection of primary and backup nodes for partition with primary node always first |