VirtualNodes

The number of virtual nodes to use in your distributed system.

When you set UseConsistentHashing to true, DIH distributes content between virtual nodes, which it assigns to one or more child servers. This method allows you to add, remove, or change the weight of a child server without reindexing all your content.

VirtualNodes specifies the number of virtual nodes to create in your system when you set up a new consistent hashing system. DIH rounds this value up to the nearest power of two (for example, if you set VirtualNodes to 4000, it creates 4096 virtual nodes.

Autonomy recommends that you set the value of VirtualNodes to be an order of magnitude higher than the number of child servers you expect to use.

The minimum value is the higher number of 33 (that is 64 nodes) or the number of child servers in your system. If you create fewer virtual nodes than there are child servers, DIH does not start. In general, Autonomy recommends that you do not reduce the default value of virtual nodes.

Note: You cannot change the number of virtual nodes in your system. If you want to change this number, you must use a clean DIH installation and reindex all your content.

Type: Long
Default: 4096
Allowed Range: Minimum: 33
Recommended Range: Minimum: 4096
Required: No
Configuration Section: ConsistentHashing
Example: VirtualNodes=8000
See Also: UseConsistentHashing

 


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