Tomcat ログに次の例外が表示され続けます。
com.mchange.v2.async.ThreadPoolAsynchronousRunner$DeadlockDetector run
WARNING: com.mchange.v2.async.ThreadPoolAsynchronousRunner$DeadlockDetector@76b28200 -- APPARENT DEADLOCK!!! Creating emergency threads for unassigned pending tasks!
com.mchange.v2.async.ThreadPoolAsynchronousRunner$DeadlockDetector run
WARNING: com.mchange.v2.async.ThreadPoolAsynchronousRunner$DeadlockDetector@76b28200 -- APPARENT DEADLOCK!!! Complete Status:
Managed Threads: 3
Active Threads: 3
Active Tasks:
com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@1201fd18 (com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#1)
com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@408f3be4 (com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#0)
com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@7ba516d8 (com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#2)
Pending Tasks:
com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@137efe53
com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@766b0524
Pool thread stack traces:
Thread[com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#1,5,main]
java.lang.Thread.sleep(Native Method)
com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1805)
com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)
Thread[com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#0,5,main]
java.lang.Thread.sleep(Native Method)
com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1805)
com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)
Thread[com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#2,5,main]
java.lang.Thread.sleep(Native Method)
com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1805)
com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)
MySQL で Hibernate 3.6.2 と C3P0 0.9.1.2 を使用しています。数時間 Google を検索した後、この APPARENT DEADLOCK 例外は通常、準備済みステートメントのキャッシュに関連付けられているようです。これは、私の hibernate.cfg.xml の C3P0 構成です。
<propertyname="connection.provider_class">org.hibernate.connection.C3P0ConnectionProvider</property>
<property name="hibernate.c3p0.acquire_increment">5</property>
<property name="hibernate.c3p0.min_size">5</property>
<property name="hibernate.c3p0.max_size">60</property>
<property name="hibernate.c3p0.idle_test_period">120</property>
<property name="hibernate.c3p0.timeout">180</property>
<property name="hibernate.c3p0.max_statements">0</property>
私はステートメントキャッシングを一切行っていません。ここで何が間違っているかについてのヒントをいただければ幸いです。