[ZOOKEEPER-1620] NIOServerCnxnFactory (new code introduced in ZK-1504) opens selectors but never closes them

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 3.5.0
• Fix Version/s: 3.5.0
• Component/s: server
• Hadoop Flags: Reviewed
• Assignee: Thawan Kooburat
• Reporter: Alexander Shraer
• Created: 15/Jan/13 04:18
• Updated: 02/May/13 02:30
• Resolved: 25/Jan/13 06:47

Description

New code (committed in ZK-1504) opens selectors but doesn't close them.
Specifically AbstractSelectThread in its constructor does

this.selector = Selector.open();

But possibly also elsewhere. Tests fail for me with the following message:

java.io.IOException: Too many open files
at sun.nio.ch.EPollArrayWrapper.epollCreate(Native Method)
at sun.nio.ch.EPollArrayWrapper.<init>(EPollArrayWrapper.java:69)
at sun.nio.ch.EPollSelectorImpl.<init>(EPollSelectorImpl.java:52)
at sun.nio.ch.EPollSelectorProvider.openSelector(EPollSelectorProvider.java:18)
at java.nio.channels.Selector.open(Selector.java:209)
at org.apache.zookeeper.server.NIOServerCnxnFactory$AbstractSelectThread.<init>(NIOServerCnxnFactory.java:128)
at org.apache.zookeeper.server.NIOServerCnxnFactory$AcceptThread.<init>(NIOServerCnxnFactory.java:177)
at org.apache.zookeeper.server.NIOServerCnxnFactory.configure(NIOServerCnxnFactory.java:663)
at org.apache.zookeeper.server.ServerCnxnFactory.createFactory(ServerCnxnFactory.java:127)
at org.apache.zookeeper.server.quorum.QuorumPeer.<init>(QuorumPeer.java:709)
at org.apache.zookeeper.test.QuorumBase.startServers(QuorumBase.java:177)
at org.apache.zookeeper.test.QuorumBase.setUp(QuorumBase.java:113)
at org.apache.zookeeper.test.QuorumBase.setUp(QuorumBase.java:71)
at org.apache.zookeeper.test.ReconfigTest.setUp(ReconfigTest.java:56)

Issue Links

• is depended upon by: ZOOKEEPER-107 Allow dynamic changes to server cluster membership
• is related to: ZOOKEEPER-1504 Multi-thread NIOServerCnxn