[DBCP-270] Dead lock using the evictor

• Type: Bug
• Status: Closed
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: 1.2.2
• Fix Version/s: 1.3
• Assignee: Unassigned
• Reporter: Filip Hanik
• Created: 26/Jun/08 17:18
• Updated: 15/Feb/10 02:35
• Resolved: 27/Jun/08 02:51

Description

Patch attached, dead lock reported. the abandonedtrace does synchronized(this) when it really only needs to do synchronized(this.trace)

Dead lock reported when using the evictor

=============================
"Timer-3":
waiting to lock monitor 0x0000000053b40548 (object 0x00002aaabf3210f0, a
org.apache.tomcat.dbcp.dbcp.PoolableConnection),
which is held by "TP-Processor27"
"TP-Processor27":
waiting to lock monitor 0x0000000053b404d0 (object 0x00002aaab9fa8b08, a
org.apache.tomcat.dbcp.pool.impl.GenericObjectPool),
which is held by "Timer-3"

Java stack information for the threads listed above:
===================================================
"Timer-3":
at
org.apache.tomcat.dbcp.dbcp.AbandonedTrace.addTrace(AbandonedTrace.java:175)

• waiting to lock <0x00002aaabf3210f0> (a
  org.apache.tomcat.dbcp.dbcp.PoolableConnection)
  at
  org.apache.tomcat.dbcp.dbcp.AbandonedTrace.init(AbandonedTrace.java:92)
  at
  org.apache.tomcat.dbcp.dbcp.AbandonedTrace.<init>(AbandonedTrace.java:82)
  at
  org.apache.tomcat.dbcp.dbcp.DelegatingStatement.<init>(DelegatingStatement.java:61)
  at
  org.apache.tomcat.dbcp.dbcp.DelegatingConnection.createStatement(DelegatingConnection.java:224)
  at
  org.apache.tomcat.dbcp.dbcp.PoolableConnectionFactory.validateConnection(PoolableConnectionFactory.java:331)
  at
  org.apache.tomcat.dbcp.dbcp.PoolableConnectionFactory.validateObject(PoolableConnectionFactory.java:312)
  at
  org.apache.tomcat.dbcp.pool.impl.GenericObjectPool.evict(GenericObjectPool.java:1217)
• locked <0x00002aaab9fa8b08> (a
  org.apache.tomcat.dbcp.pool.impl.GenericObjectPool)
  at
  org.apache.tomcat.dbcp.pool.impl.GenericObjectPool$Evictor.run(GenericObjectPool.java:1341)
  at java.util.TimerThread.mainLoop(Timer.java:512)
  at java.util.TimerThread.run(Timer.java:462)
  "TP-Processor27":
  at
  org.apache.tomcat.dbcp.pool.impl.GenericObjectPool.addObjectToPool(GenericObjectPool.java:1136)
• waiting to lock <0x00002aaab9fa8b08> (a
  org.apache.tomcat.dbcp.pool.impl.GenericObjectPool)
  at
  org.apache.tomcat.dbcp.pool.impl.GenericObjectPool.returnObject(GenericObjectPool.java:1076)
  at
  org.apache.tomcat.dbcp.dbcp.PoolableConnection.close(PoolableConnection.java:87)
• locked <0x00002aaabf3210f0> (a
  org.apache.tomcat.dbcp.dbcp.PoolableConnection)
  ....