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 ICacheAffinityProperties
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 |