jconsole观察c3p0，发现不停地有阻塞

Question

c3p0有时候会报错，导致容器重新启动，服务挂掉。

使用jconsole进行监控，线程里面信息显示如下：

名称： C3P0PooledConnectionPoolManager[identityToken->1hgf4eq8z1z3fxm1jik78a|92992c]-HelperThread-#0

状态：TIMED_WAITING 在 com.mchange.v2.async.ThreadPoolAsynchronousRunner@1877fa7 上
阻塞总数：463,725  等待总数： 473,434

堆栈追踪： 
java.lang.Object.wait(Native Method)
com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:635)

谁知道为什么会不断地阻塞？这种情况正常么？

tomcat日志报错信息：

2013-12-11 09:23:07 [com.mchange.v2.async.ThreadPoolAsynchronousRunner]-[WARN] com.mchange.v2.async.ThreadPoolAsynchronousRunner$DeadlockDetector@177bb7a -- APPARENT DEADLOCK!!! Creating emergency threads for unassigned pending tasks!
2013-12-11 09:23:07 [com.mchange.v2.async.ThreadPoolAsynchronousRunner]-[WARN] com.mchange.v2.async.ThreadPoolAsynchronousRunner$DeadlockDetector@177bb7a -- APPARENT DEADLOCK!!! Complete Status: 
Managed Threads: 3
Active Threads: 3
Active Tasks: 
com.mchange.v2.resourcepool.BasicResourcePool$AsyncTestIdleResourceTask@276565
on thread: C3P0PooledConnectionPoolManager[identityToken->1hgf4eq8y1jdz3or1h42r0d|13a6057]-HelperThread-#1
com.mchange.v2.resourcepool.BasicResourcePool$AsyncTestIdleResourceTask@71fc3b
on thread: C3P0PooledConnectionPoolManager[identityToken->1hgf4eq8y1jdz3or1h42r0d|13a6057]-HelperThread-#2
com.mchange.v2.resourcepool.BasicResourcePool$AsyncTestIdleResourceTask@16689d1
on thread: C3P0PooledConnectionPoolManager[identityToken->1hgf4eq8y1jdz3or1h42r0d|13a6057]-HelperThread-#0
Pending Tasks: 
com.mchange.v2.resourcepool.BasicResourcePool$AsyncTestIdleResourceTask@e23387

Answer 1

这个改个配置就好了

Answer 2

@177bb7a 看看这个地址被谁拿着呢

Answer 3

现象是死锁，其实数据库没死锁，线程池死锁，还有jconsole监控的数据，c3p0连接池的问题么？