[KAFKA-3689] Exception when attempting to decrease connection count for address with no connections

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.9.0.1
• Component/s: network

Environment

ubuntu 14.04,

java version "1.7.0_95"
OpenJDK Runtime Environment (IcedTea 2.6.4) (7u95-2.6.4-0ubuntu0.14.04.2)
OpenJDK 64-Bit Server VM (build 24.95-b01, mixed mode)

3 broker cluster (all 3 servers identical - Intel Xeon E5-2670 @2.6GHz, 8cores, 16 threads 64 GB RAM & 1 TB Disk)

Kafka Cluster is managed by 3 server ZK cluster (these servers are different from Kafka broker servers). All 6 servers are connected via 10G switch.

Producers run from external servers.

• Flags: Patch, Important
• Assignee: Ryan P
• Reporter: Buvaneswari Ramanan
• Reviewer: Ismael Juma
• Created: 10/May/16 18:03
• Updated: 09/May/18 14:45
• Resolved: 09/May/18 14:45

Description

As per Ismael Juma's suggestion in email thread to [e-mail] with the same subject, I am creating this bug report.

The following error occurs in one of the brokers in our 3 broker cluster, which serves about 8000 topics. These topics are single partitioned with a replication factor = 3. Each topic gets data at a low rate – 200 bytes per sec. Leaders are balanced across the topics.

Producers run from external servers (4 Ubuntu servers with same config as the brokers), each producing to 2000 topics utilizing kafka-python library.

This error message occurs repeatedly in one of the servers. Between the hours of 10:30am and 1:30pm on 5/9/16, there were about 10 Million such occurrences. This was right after a cluster restart.

This is not the first time we got this error in this broker. In those instances, error occurred hours / days after cluster restart.

=====================================================

[2016-05-09 10:38:43,932] ERROR Processor got uncaught exception. (kafka.network.Processor)
java.lang.IllegalArgumentException: Attempted to decrease connection count for address with no connections, address: /X.Y.Z.144 (actual network address masked)
at kafka.network.ConnectionQuotas$$anonfun$9.apply(SocketServer.scala:565)
at kafka.network.ConnectionQuotas$$anonfun$9.apply(SocketServer.scala:565)
at scala.collection.MapLike$class.getOrElse(MapLike.scala:128)
at scala.collection.AbstractMap.getOrElse(Map.scala:59)
at kafka.network.ConnectionQuotas.dec(SocketServer.scala:564)
at kafka.network.Processor$$anonfun$run$13.apply(SocketServer.scala:450)
at kafka.network.Processor$$anonfun$run$13.apply(SocketServer.scala:445)
at scala.collection.Iterator$class.foreach(Iterator.scala:742)
at scala.collection.AbstractIterator.foreach(Iterator.scala:1194)
at scala.collection.IterableLike$class.foreach(IterableLike.scala:72)
at scala.collection.AbstractIterable.foreach(Iterable.scala:54)
at kafka.network.Processor.run(SocketServer.scala:445)
at java.lang.Thread.run(Thread.java:745)
[2016-05-09 10:38:43,932] ERROR Processor got uncaught exception. (kafka.network.Processor)
java.lang.IllegalArgumentException: Attempted to decrease connection count for address with no connections, address: /X.Y.Z.144
at kafka.network.ConnectionQuotas$$anonfun$9.apply(SocketServer.scala:565)
at kafka.network.ConnectionQuotas$$anonfun$9.apply(SocketServer.scala:565)
at scala.collection.MapLike$class.getOrElse(MapLike.scala:128)
at scala.collection.AbstractMap.getOrElse(Map.scala:59)
at kafka.network.ConnectionQuotas.dec(SocketServer.scala:564)
at kafka.network.Processor$$anonfun$run$13.apply(SocketServer.scala:450)
at kafka.network.Processor$$anonfun$run$13.apply(SocketServer.scala:445)
at scala.collection.Iterator$class.foreach(Iterator.scala:742)
at scala.collection.AbstractIterator.foreach(Iterator.scala:1194)
at scala.collection.IterableLike$class.foreach(IterableLike.scala:72)
at scala.collection.AbstractIterable.foreach(Iterable.scala:54)
at kafka.network.Processor.run(SocketServer.scala:445)
at java.lang.Thread.run(Thread.java:745)

Issue Links

• is related to: KAFKA-3986 completedReceives can contain closed channels
• links to: GitHub Pull Request #1658
• links to: GitHub Pull Request #1658