UseConsistentHashing

Set this parameter to true to use the DIH consistent hashing mode with the DistributeByReference or DistributeByFields distribution modes. In consistent hashing mode, you can add, remove, or change the weight of child servers in your DIH without having to reindex all your content.

In this mode, DIH distributes documents among a large, fixed number of virtual nodes, and then assigns these nodes to one or more child servers. When you change the number or weight of child servers, you can use the DREREDISTRIBUTE index action to redistribute the virtual nodes between the new set of servers without reindexing all the data.

To use consistent hashing, you must configure a new field process in all of the child servers to set the */DREVNODE to use the ReferenceType, and TrimSpaces. You might also want to use the HiddenType property for this field. You must use a new field process, rather than adding it to an existing reference field process. For example:

[FieldProcessing]
0=SetVNodeReferenceField
			
[SetVNodeReferenceField]
Property=VNodeReferenceField
PropertyFieldCSVs=*/DREVNODE
			
[VNodeReferenceField]
ReferenceType=TRUE
TrimSpaces=TRUE
HiddenType=TRUE

For more details about field processes, refer to the IDOL Server Reference.

Note: When you initially switch from the default mode to consistent hashing mode, you must reindex your data.

For more information about consistent hashing mode, refer to the DIH Administration Guide.

Type: Boolean
Default: False
Required: No
Configuration Section: Server
Example: UseConsistentHashing=true
See Also:

DistributeByReference

DistributeByFields

Replicas

VirtualNodes

DREREDISTRIBUTE index action


© 2013 Hewlett-Packard Development Company, L.P.