一种unable to create new native thread问题

问题:使用EhCache按期更新数据库时,每隔几天,Tomcat抛下面异常,致使更新失败.

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'cacheManager' defined in class path resource [configs/applicationContext.xml]: Invocation of init method failed; nested exception is java.lang.OutOfMemoryError: unable to create new native thread

    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1420)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:519)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:456)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:291)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:288)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:190)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:563)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:895)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:425)
    at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:139)
    at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:83)
    at com.moonbasa.erp.analytics.abtest.cache.EhCacheEventListener.notifyElementExpired(EhCacheEventListener.java:31)
    at net.sf.ehcache.event.RegisteredEventListeners.notifyListener(RegisteredEventListeners.java:286)
    at net.sf.ehcache.event.RegisteredEventListeners.invokeListener(RegisteredEventListeners.java:272)
    at net.sf.ehcache.event.RegisteredEventListeners.internalNotifyElementExpiry(RegisteredEventListeners.java:208)
    at net.sf.ehcache.event.RegisteredEventListeners.notifyElementExpiry(RegisteredEventListeners.java:186)
    at net.sf.ehcache.Cache.notifyRemoveInternalListeners(Cache.java:2160)
    at net.sf.ehcache.Cache.removeInternal(Cache.java:2148)
    at net.sf.ehcache.Cache.tryRemoveImmediately(Cache.java:1960)
    at net.sf.ehcache.Cache.searchInStoreWithoutStats(Cache.java:1937)
    at net.sf.ehcache.Cache.get(Cache.java:1555)
    at net.sf.ehcache.Cache.get(Cache.java:1522)
    at com.moonbasa.erp.analytics.abtest.servlets.CountServlet.doGet(CountServlet.java:48)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:304)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:224)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:185)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:151)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:929)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:405)
    at org.apache.coyote.http11.Http11NioProcessor.process(Http11NioProcessor.java:317)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:515)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1544)
    at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
    at java.lang.Thread.run(Thread.java:619)
Caused by: java.lang.OutOfMemoryError: unable to create new native thread
    at java.lang.Thread.start0(Native Method)
    at java.lang.Thread.start(Thread.java:597)
    at java.util.Timer.<init>(Timer.java:154)
    at net.sf.ehcache.util.FailSafeTimer.<init>(FailSafeTimer.java:52)
    at net.sf.ehcache.CacheManager.init(CacheManager.java:369)
    at net.sf.ehcache.CacheManager.<init>(CacheManager.java:289)
    at org.springframework.cache.ehcache.EhCacheManagerFactoryBean.afterPropertiesSet(EhCacheManagerFactoryBean.java:112)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1477)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1417)

    ... 41 more

可能缘由:

"该异常由栈中抛出, 代表栈中无可用内存来服务线程。而JVM的内存大体可分为（这里不够严谨）内存数据区（包括Stack）+对象堆区，因为JVM实例进程寻址是必定的。因此二者此消彼涨的关系，对于32位的机子, JVM整个实例可用内存不到3G，加上个人Heap Size 设置了2G，留给数据区只有1G不到,  当时系统跑了大概500+的线程, 按照JDK1.5以来, 每一个线程栈的大小为1M, 这样算出溢出就差很少了。"

                                                                                                        ----转自互联网

解决办法:

1.减少-Xss512k： 设置每一个线程的堆栈大小。JDK5.0之后每一个线程堆栈大小为1M，之前每一个线程堆栈大小为256K。更具应用的线程所需内存大小进行调整。在相同物理内 存下，减少这个值能生成更多的线程。可是操做系统对一个进程内的线程数仍是有限制的，不能无限生成，经验值在3000~5000左右。

2.减少-Xms512m -Xmx512m

3.升级CPU至64位