[ZOOKEEPER-2] Synchronization issues in QuorumPeer and FastLeader election

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 3.0.0
• Component/s: leaderElection
• Hadoop Flags: Reviewed
• Assignee: Flavio Paiva Junqueira
• Reporter: Benjamin Reed
• Created: 09/Jun/08 16:34
• Updated: 09/Sep/08 21:11
• Resolved: 25/Aug/08 21:13

Description

There are a couple of cases of member variables that need to be marked volatile or surrounded in a synchronization block. A couple of examples are:

• QuorumPeer state should be synchronous
• currentVote in QuorumPeer is marked volatile, but when it's members are often accessed individually as if they were in an atomic unit. Such code should be changed to get a reference to the currentVote and they access members through that reference.
• It looks like logicalClock in FastLeaderElection should be volatile. It should either be fixed or commented to explain why it doesn't need to be.