Read requests are handled locally at each Zookeeper server. So it is
possible for a read request to return a stale value even though a more
recent update to the same znode has been committed. Does this statement
still hold if the Zookeeper follower serving the read request is the one
which has just served the recent update request?

For example, client A connects to follower X. And client A issues a request
to update znode /a from 0 to 1. After receiving this request, follower X
forwards this request to the leader. Then the leader broadcasts this update
proposal to all the Zookeeper servers. After a quorum of the followers
commit the update request, the update succeeds. Then client A issues a read
request to get the value of znode /a. And follower X receives this read
request. So if follower X is not among the quorum and follower X has not
committed the update to catch up with the leader, it is still possible for
client A to get a stale value of znode /a. In this case, the return value is

Is my understanding correct?

Jingguo Yao

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