All cluster members must have the same amount of memory dedicated to the Couchbase server. It is essential that virtual memory not be used.
It is recommended that a minimum of 4GB RAM be allocated to a Couchbase node. Half of the allocated memory will be available to the node, and half will be used to replicate data from other nodes.
If 4GB RAM are dedicated to the Couchbase node, at least 8GB RAM should be available on the virtual machine.