How does stale query work?

Note that as of 3.0, the semantics of stale=false have changed slightly. It now means whatever is current in the active location for the vbuckets, which is closer to user intent and is actually faster in 3.0 than it was in 2.0.

It also means you no longer need to wait for persistence before querying a view.

See the 3.0 release notes for details.