[CASSANDRA-5175] Unbounded (?) thread growth connecting to an removed node

• Type: Bug
• Status: Resolved
• Priority: Low
• Resolution: Fixed
• Fix Version/s: 1.1.10, 1.2.1

Environment

EC2, JDK 7u9, Ubuntu 12.04.1 LTS

• Severity: Low
• Assignee: Vijay
• Reporter: Janne Jalkanen

Authors

Vijay

Reviewers

Brandon Williams

• Created: 19/Jan/13 19:52
• Updated: 16/Apr/19 09:32
• Resolved: 23/Jan/13 06:48

Description

The following lines started repeating every minute in the log file

 INFO [GossipStage:1] 2013-01-19 19:35:43,929 Gossiper.java (line 831) InetAddress /10.238.x.y is now dead.
 INFO [GossipStage:1] 2013-01-19 19:35:43,930 StorageService.java (line 1291) Removing token 170141183460469231731687303715884105718 for /10.238.x.y

Also, I got about 3000 threads which all look like this:

Name: WRITE-/10.238.x.y
State: WAITING on java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject@1bb65c0f
Total blocked: 0  Total waited: 3

Stack trace: 
 sun.misc.Unsafe.park(Native Method)
java.util.concurrent.locks.LockSupport.park(LockSupport.java:186)
java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2043)
java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
org.apache.cassandra.net.OutboundTcpConnection.run(OutboundTcpConnection.java:104)

A new thread seems to be created every minute, and they never go away.

The endpoint in question had been a part of the cluster weeks ago, and the node exhibiting the thread growth was added yesterday.

Anyway, assassinating the endpoint in question stopped thread growth (but kept the existing threads running), so this isn't a huge issue. But I don't think the thread count is supposed to be increasing like this...