Github user shralex commented on a diff in the pull request:
https://github.com/apache/zookeeper/pull/438#discussion_r179363930
--- Diff: src/java/main/org/apache/zookeeper/server/quorum/Leader.java ---
@@ -1183,8 +1183,10 @@ public long getEpochToPropose(long sid, long
lastAcceptedEpoch) throws Interrupt
if (lastAcceptedEpoch >= epoch) {
epoch = lastAcceptedEpoch+1;
}
- connectingFollowers.add(sid);
QuorumVerifier verifier = self.getQuorumVerifier();
+ if(verifier.getVotingMembers().containsKey(sid)) {
--- End diff --
If I recall correctly, the reason this wasn't done are concerns around the
impact on performance - containsQuorum is called every time an ACK is received
for every operation proposal. So if you need 3 asks to commit an operation,
we'll be doing these checks (figuring out who's a participant and who's not}
for {ACK1}, for {ACK1, ACK2} and for {ACK1, ACK2, ACK3}. This compared to
comparing two ints as it stands now. So this is why it wasn't done...
---
