Tomcat 6内存泄漏日志条目

Question

以下是我在CentOS机器上的Catalina.out文件中输入的唯一条目.我正在使用Spring 3和我的应用程序运行Tomcat 6.有很多这样的,所以我选择了一些不断重复的东西.这不会一直发生,但每周至少发生一次.

问题是我该如何防止波纹发生？

Feb 3, 2011 2:37:48 PM org.apache.catalina.loader.WebappClassLoader clearReferencesJdbc

SEVERE: The web application [] registered the JBDC driver [com.mysql.jdbc.Driver] but failed to unregister it when the web application was stopped. To prevent a memory leak, the JDBC Driver has been forcibly unregistered.

Feb 3, 2011 2:37:48 PM org.apache.catalina.loader.WebappClassLoader clearReferencesThreads

SEVERE: The web application [] appears to have started a thread named [com.iteezy.shared.domain.DirEntry.data] but has failed to stop it. This is very likely to create a memory leak.


Feb 3, 2011 2:37:48 PM org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
SEVERE: The web application [] appears to have started a thread named

[com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#0] but has failed to stop it. This is very likely to create a memory leak.


Feb 3, 2011 2:37:48 PM org.apache.catalina.loader.WebappClassLoader clearReferencesThreads  

SEVERE: The web application [] appears to have started a thread named [File Reaper] but has failed to stop it. This is very likely to create a memory leak.

Feb 3, 2011 2:37:48 PM org.apache.catalina.loader.WebappClassLoader clearReferencesThreads

SEVERE: The web application [] appears to have started a thread named [pool-1-thread-22] but has failed to stop it. This is very likely to create a memory leak.  

37:48 PM org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
b application [] appears to have started a thread named 

[org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-2] but has failed to stop it. This is very likely to create a memory leak.

37:48 PM org.apache.catalina.loader.WebappClassLoader clearThreadLocalMap

b application [] created a ThreadLocal with key of type [net.sf.json.AbstractJSON$1] (value [net.sf.json.AbstractJSON$1@40bbb3d6]) and a value of type [java.util.HashSet] (value [[]]) but failed to remove it when the web application was stopped. This is very likely to create a memory leak.

Answer 1

当你定义一个外部标志,一个线程被假定为轮询并在它被设置时退出 - 它必须是volatile.否则,线程可能永远不会看到其他线程所做的更改.

但是在标准API中已经存在类似的功能 - 它被称为interrupt()方法和Thread.currentThread().isInterrupted().无需复制已有的逻辑.请参阅:停止特定的Java线程.

也就是说,调用interrupt()每个线程也是一个坏主意,因为无法保证所有线程都响应它.检查您的异常我注意到以下线程未正确清理:

• com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#0 - 关闭C3P0数据源.因为你使用Spring只需添加destroy-method="close".我们完成了这个线程.

• File Reaper- 据我所知,这个线程是由FileCleaningTracker创建的.FileCleaningTracker.exitWhenFinished()关闭应用程序时需要显式调用(或者不再需要类时,我从不使用它)或者让Spring执行此操作(参见上文).有些第三方库可能会使用它并且没有正确关闭 - 这意味着它有一个错误.

• pool-1-thread-22- 这是由Executors实用程序内部创建的线程之一ExecutorService.确保shutdown()在关机期间调用应用程序中的每个这样的池.

• org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-2 - Quartz工作线程(实际运行作业的线程).SchedulerFactoryBean自动关闭调度程序,我认为Tomcat在这里是错误的,我也常常看到这个错误.不过貌似设置SchedulerFactoryBean.waitForJobsToCompleteOnShutdown来true解决这个问题.

• com.iteezy.shared.domain.DirEntry.data - 我不确定这个.它是您自己的线程,需要在关机时中断或H2数据库线程(？)需要检查其堆栈以猜测它来自何处.

底线是:不要只是杀死所有移动的东西(实际上,Tomcat在发出此警告后为您执行此操作)但确定线程来自何处并使用框架/库特定close()方法来允许进一步清理.要温柔.