Gary Tully created AMQ-5984:
-------------------------------
Summary: Unsafe use of access-order LinkedHashMap via
ActiveMQMessageAuditNoSync - can lead to loop and hang
Key: AMQ-5984
URL: https://issues.apache.org/jira/browse/AMQ-5984
Project: ActiveMQ
Issue Type: Bug
Components: Broker
Affects Versions: 5.12.0
Reporter: Gary Tully
Assignee: Gary Tully
Fix For: 5.13.0
A thread looping in{code}"ActiveMQ Transport: tcp:///xxx:yyy@61616" daemon
prio=10 tid=0x00007efff40a3000 nid=0x74f0 runnable [0x00007eff6f0f9000]
java.lang.Thread.State: RUNNABLE
at java.util.LinkedHashMap.transfer(LinkedHashMap.java:253)
at java.util.HashMap.resize(HashMap.java:581)
at java.util.HashMap.addEntry(HashMap.java:879)
at java.util.LinkedHashMap.addEntry(LinkedHashMap.java:427)
at java.util.HashMap.put(HashMap.java:505)
at
org.apache.activemq.ActiveMQMessageAuditNoSync.isDuplicate(ActiveMQMessageAuditNoSync.java:133)
at
org.apache.activemq.store.kahadb.MessageDatabase.upadateIndex(MessageDatabase.java:1238)
at
org.apache.activemq.store.kahadb.MessageDatabase$AddOpperation.execute(MessageDatabase.java:2196)
at
org.apache.activemq.store.kahadb.MessageDatabase$15.execute(MessageDatabase.java:1141)
at
org.apache.activemq.store.kahadb.disk.page.Transaction.execute(Transaction.java:779)
at
org.apache.activemq.store.kahadb.MessageDatabase.process(MessageDatabase.java:1137)
at
org.apache.activemq.store.kahadb.MessageDatabase$10.visit(MessageDatabase.java:1005)
at
org.apache.activemq.store.kahadb.data.KahaCommitCommand.visit(KahaCommitCommand.java:130)....{code}
points to the need for a write lock on access to the LRUCache used for
duplicate detection for failover producers.
The index lock protects modifications on put etc but clearly a get needs to
have exclusive access. Tis in the javadoc in bold - "In access-ordered linked
hash maps, merely querying the map with get is a structural modification"
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
