In our production environment, weblogic server hangs for half an hour, It looks like it has dead-locked threads. But after investigating thread dumps, 3 threads are blocked for the same lock, but no other threads own this lock.. Here is the stacktrace..
Do you have any reasonable explanation for this stiuation?.
Here is the blocked threads;
"pool-1013-thread-5" prio=7 tid=600000000842be00 nid=17280 lwp_id=518677 waiting for monitor entry [9fffffffe6aff000..9fffffffe6b00bd0] java.lang.Thread.State: BLOCKED (on object monitor) at org.apache.log4j.Category.callAppenders(Category.java:201) - waiting to lock <9ffffffde1e7ec88> (a org.apache.log4j.spi.RootLogger) at org.apache.log4j.Category.forcedLog(Category.java:388) at org.apache.log4j.Category.log(Category.java:853) at org.slf4j.impl.Log4jLoggerAdapter.debug(Log4jLoggerAdapter.java:173) at org.hibernate.jdbc.AbstractBatcher.logOpenResults(AbstractBatcher.java:426) at org.hibernate.jdbc.AbstractBatcher.getResultSet(AbstractBatcher.java:210) at org.hibernate.loader.Loader.getResultSet(Loader.java:1808)
"pool-1013-thread-4" prio=7 tid=6000000008413400 nid=17279 lwp_id=518676 waiting for monitor entry [9fffffffe6eff000..9fffffffe6f00b50] java.lang.Thread.State: BLOCKED (on object monitor) at org.apache.log4j.Category.callAppenders(Category.java:201) - waiting to lock <9ffffffde1e7ec88> (a org.apache.log4j.spi.RootLogger) at org.apache.log4j.Category.forcedLog(Category.java:388) at org.apache.log4j.Category.log(Category.java:853) at org.slf4j.impl.Log4jLoggerAdapter.debug(Log4jLoggerAdapter.java:173) at org.hibernate.loader.Loader.getRow(Loader.java:1197) at org.hibernate.loader.Loader.getRowFromResultSet(Loader.java:603) at org.hibernate.loader.Loader.doQuery(Loader.java:724) at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:259) at org.hibernate.loader.Loader.loadEntity(Loader.java:1881) at org.hibernate.loader.entity.AbstractEntityLoader.load(AbstractEntityLoader.java:71) at org.hibernate.loader.entity.AbstractEntityLoader.load(AbstractEntityLoader.java:65) at org.hibernate.persister.entity.AbstractEntityPersister.load(AbstractEntityPersister.java:3072) at org.hibernate.event.def.DefaultLoadEventListener.loadFromDatasource(DefaultLoadEventListener.java:434) at org.hibernate.event.def.DefaultLoadEventListener.doLoad(DefaultLoadEventListener.java:415) at org.hibernate.event.def.DefaultLoadEventListener.load(DefaultLoadEventListener.java:165) at org.hibernate.event.def.DefaultLoadEventListener.proxyOrLoad(DefaultLoadEventListener.java:223) at org.hibernate.event.def.DefaultLoadEventListener.onLoad(DefaultLoadEventListener.java:126) at org.hibernate.impl.SessionImpl.fireLoad(SessionImpl.java:905)
"pool-1013-thread-3" prio=7 tid=6000000008411c00 nid=17278 lwp_id=518675 waiting for monitor entry [9fffffffe70ff000..9fffffffe7100ad0] java.lang.Thread.State: BLOCKED (on object monitor) at org.apache.log4j.Category.callAppenders(Category.java:201) - waiting to lock <9ffffffde1e7ec88> (a org.apache.log4j.spi.RootLogger) at org.apache.log4j.Category.forcedLog(Category.java:388) at org.apache.log4j.Category.log(Category.java:853) at org.slf4j.impl.Log4jLoggerAdapter.debug(Log4jLoggerAdapter.java:173) at org.hibernate.jdbc.AbstractBatcher.logOpenResults(AbstractBatcher.java:426) at org.hibernate.jdbc.AbstractBatcher.getResultSet(AbstractBatcher.java:210) at org.hibernate.loader.Loader.getResultSet(Loader.java:1808) at org.hibernate.loader.Loader.doQuery(Loader.java:697)