permgen

I have a perm gen memory leak, that I know. Profiling using jvisualvm shows that when doing hot deployment (e.g. stop and start an application without killing the JVM, in tomcat, WebSphere, WebLogic etc) - the PermGen space is constantly increasing. After reading, using jhat, and other advanced tools I realized that I probably have a reference to the WebAppClassLoader from a class somewhere in its parent class loaders. I couldn't pin it down even though I did some massive JavaScript based queries on jhat Isn't there a simple utility that finds out who is responsible for you class loader to not

I've seen many primitive examples describing how String intern()'ing works, but I have yet to see a real-life use-case that would benefit from it. The only situation that I can dream up is having a web service that receives a considerable amount of requests, each being very similar in nature due to a rigid schema. By intern()'ing the request field names in this case, memory consumption can be significantly reduced. Can anyone provide an example of using intern() in a production environment with great success? Maybe an example of it in a popular open source offering? Edit: I am referring to

I need help with this problem. I need someone to explain to me why is this happening and how to prevent or avoid it. Exception in thread "Thread-747" java.lang.OutOfMemoryError: PermGen space Exception in thread "Thread-748" java.lang.OutOfMemoryError: PermGen space Exception in thread "Thread-759" java.lang.OutOfMemoryError: PermGen space Exception in thread "Thread-760" java.lang.OutOfMemoryError: PermGen space Exception in thread "Thread-764" java.lang.OutOfMemoryError: PermGen space Exception in thread "Thread-765" java.lang.OutOfMemoryError: PermGen space Exception in thread "Thread-766"

java.lang.OutOfMemoryError这个错误我相信大部分开发人员都有遇到过，产生该错误的原因大都出于以下原因：JVM内存过小、程序不严密，产生了过多的垃圾。 导致OutOfMemoryError异常的常见原因有以下几种： 内存中加载的数据量过于庞大，如一次从数据库取出过多数据； 集合类中有对对象的引用，使用完后未清空，使得JVM不能回收； 代码中存在死循环或循环产生过多重复的对象实体； 使用的第三方软件中的BUG； 启动参数内存值设定的过小； 此错误常见的错误提示： tomcat:java.lang.OutOfMemoryError: PermGen space tomcat:java.lang.OutOfMemoryError: Java heap space weblogic:Root cause of ServletException java.lang.OutOfMemoryError resin:java.lang.OutOfMemoryError java:java.lang.OutOfMemoryError 解决java.lang.OutOfMemoryError的方法有如下几种： 一、增加jvm的内存大小。方法有： 1）在执行某个class文件时候，可以使用java -Xmx256M aa.class来设置运行aa

一、常见的Java内存溢出有以下三种： 1. java.lang.OutOfMemoryError: Java heap space ----JVM Heap（堆）溢出 JVM在启动的时候会自动设置JVM Heap的值，其初始空间(即-Xms)是物理内存的1/64，最大空间(-Xmx)不可超过物理内存。 可以利用JVM提供的-Xmn -Xms -Xmx等选项可进行设置。Heap的大小是Young Generation 和Tenured Generaion 之和。 在JVM中如果98％的时间是用于GC，且可用的Heap size 不足2％的时候将抛出此异常信息。 解决方法：手动设置JVM Heap（堆）的大小。 2. java.lang.OutOfMemoryError: PermGen space ---- PermGen space溢出。 PermGen space的全称是Permanent Generation space，是指内存的永久保存区域。 为什么会内存溢出，这是由于这块内存主要是被JVM存放Class和Meta信 息的，Class在被Load的时候被放入PermGen space区域，它和存放Instance的Heap区域不同,sun的 GC不会在主程序运行期对PermGen space进行清理，所以如果你的APP会载入很多CLASS的话，就很可能出现PermGen

We have had our glassfish instance go down every two weeks for a while with a java.lang.OutOfMemoryError: PermGen space . I increased the PermGen space to 512MB and startet dumping memory usage with jstat -gc . After two weeks I came up with the following graph that shows how the PermGen space is steadily increasing (the units on the x-axis are minutes, y-axis are KB). I tried googling around for some kind of profiling tool that could pinpoint the error and a thread here on SO mentioned jmap, which proved to be quite helpful. Out of the approximately 14000 lines dumped from jmap -permstats