[ZOOKEEPER-1237] ERRORs being logged when queued responses are sent after socket has closed.

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Duplicate
• Affects Version/s: 3.3.4, 3.4.0, 3.5.0
• Fix Version/s: 3.4.10
• Component/s: server
• Assignee: Unassigned
• Reporter: Patrick D. Hunt
• Created: 20/Oct/11 16:54
• Updated: 31/May/18 00:16
• Resolved: 24/Jan/17 23:58

Description

After applying ZOOKEEPER-1049 to 3.3.3 (I believe the same problem exists in 3.4/3.5 but haven't tested this) I'm seeing the following exception more frequently:

Oct 19, 1:31:53 PM ERROR
Unexpected Exception:
java.nio.channels.CancelledKeyException
at sun.nio.ch.SelectionKeyImpl.ensureValid(SelectionKeyImpl.java:55)
at sun.nio.ch.SelectionKeyImpl.interestOps(SelectionKeyImpl.java:59)
at org.apache.zookeeper.server.NIOServerCnxn.sendBuffer(NIOServerCnxn.java:418)
at org.apache.zookeeper.server.NIOServerCnxn.sendResponse(NIOServerCnxn.java:1509)
at org.apache.zookeeper.server.FinalRequestProcessor.processRequest(FinalRequestProcessor.java:367)
at org.apache.zookeeper.server.quorum.CommitProcessor.run(CommitProcessor.java:73)

This is a long standing problem where we try to send a response after the socket has been closed. Prior to ZOOKEEPER-1049 this issues happened much less frequently (2 sec linger), but I believe it was possible. The timing window is just wider now.

Issue Links

• duplicates: ZOOKEEPER-2044 CancelledKeyException in zookeeper branch-3.4