If you send too many requests all at once to Couchbase, you can create a out of memory problem, and the server will send back a temporary failure message. The message indicates you can retry the operation, however the server will not slow down significantly; it just does not handle the request. In contrast, other database systems will become slower for all operations under load.

This gives your application a bit more control since the temporary failure messages gives you the opportunity to provide a backoff mechanism and retry operations in your application logic.