JVM各种内存溢出是否产生dump

     对于java的内存溢出，如果配置-XX:+HeapDumpOnOutOfMemoryError，很明确的知道堆内存溢出时会生成dump文件。但永久代内存溢出不明确是否会生成，今天来做一个实验：

永久代内存溢出，有dump文件。JVM的参数是-XX:PermSize=10m  -XX:MaxPermSize=10m   -XX:+HeapDumpOnOutOfMemoryError

import java.util.ArrayList;
import java.util.List;
public class PermPoolOOM{
    public static void main(String[] args){
        List  list = new ArrayList();
        int i = 0;
        while(true){
          list.add(String.valueOf(i++).intern());
        }
    }
}

java.lang.OutOfMemoryError: PermGen space
Dumping heap to java_pid8900.hprof ...
Heap dump file created [17009938 bytes in 0.336 secs]
Exception in thread "main" java.lang.OutOfMemoryError: PermGen space
at java.lang.String.intern(Native Method)
at PermPoolOOM.main(PermPoolOOM.java:8)

方法区溢出，有dump文件。需要下载cglib-full-2.0.1.jar，JVM参数设置：-XX:PermSize=10m  -XX:MaxPermSize=10m   -XX:+HeapDumpOnOutOfMemoryError

import java.lang.reflect.Method;
import net.sf.cglib.proxy.Enhancer;
import net.sf.cglib.proxy.MethodInterceptor;
import net.sf.cglib.proxy.MethodProxy;

public class JavaMethodAreaOOM {

    public static void main(String[] args) {
           while (true) {
                  Enhancer enhancer = new Enhancer();
                  enhancer.setSuperclass(OOMObject.class);
                  enhancer.setUseCache(false);
                  enhancer.setCallback(new MethodInterceptor() {
                         public Object intercept(Object obj, Method method, Object[] args, MethodProxy proxy) throws Throwable {
                                return proxy.invokeSuper(obj, args);
                         }
                  });
                  enhancer.create();
           }
    }
    static class OOMObject {

    }
}

java.lang.OutOfMemoryError: PermGen space
Dumping heap to java_pid11000.hprof ...
Heap dump file created [6752989 bytes in 0.075 secs]
Exception in thread "main" net.sf.cglib.core.CodeGenerationException: java.lang.reflect.InvocationTargetException-->null
at net.sf.cglib.core.AbstractClassGenerator.create(AbstractClassGenerator.java:208)
at net.sf.cglib.proxy.Enhancer.createHelper(Enhancer.java:406)
at net.sf.cglib.proxy.Enhancer.create(Enhancer.java:318)
at JavaMethodAreaOOM.main(JavaMethodAreaOOM.java:21)
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at net.sf.cglib.core.ReflectUtils.defineClass(ReflectUtils.java:411)
at net.sf.cglib.core.AbstractClassGenerator.create(AbstractClassGenerator.java:195)
... 3 more
Caused by: java.lang.OutOfMemoryError: PermGen space
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClassCond(Unknown Source)
at java.lang.ClassLoader.defineClass(Unknown Source)
... 8 more

直接内存溢出，没有dump文件。JVM参数配置：-XX:PermSize=10m  -XX:MaxPermSize=10m   -XX:+HeapDumpOnOutOfMemoryError  -XX:MaxDirectMemorySize=10M

import java.lang.reflect.Field;
import sun.misc.Unsafe;

public class DirectMemoryOOM{
    private static final int _1MB = 1024* 1024 * 1024;
    public static void main(String[] args) throws Exception{
        Field unsafeField = Unsafe.class.getDeclaredFields()[0];
        unsafeField.setAccessible(true);
        Unsafe unsafe = (Unsafe) unsafeField.get(null);
        while(true){
            //unsafe直接想操作系统申请内存
            unsafe.allocateMemory(_1MB);
        }
    }
}

Exception in thread "main" java.lang.OutOfMemoryError
at sun.misc.Unsafe.allocateMemory(Native Method)
at com.comtop.DirectMemoryOOM.main(DirectMemoryOOM.java:15)

栈内存溢出，没有dump文件。JVM参数设置:-Xss128k

public class JavaVMStackOF{
    int stackLength = 1;
    public void stackLeak(){
        stackLength++;
        stackLeak();
}
public static void main(String[] args){
    JavaVMStackOF oom = new JavaVMStackOF();
    oom.stackLeak();
}
}

Exception in thread "main" java.lang.StackOverflowError
at JavaVMStackOF.stackLeak(JavaVMStackOF.java:6)
at JavaVMStackOF.stackLeak(JavaVMStackOF.java:7)
at JavaVMStackOF.stackLeak(JavaVMStackOF.java:7)
at JavaVMStackOF.stackLeak(JavaVMStackOF.java:7)
at JavaVMStackOF.stackLeak(JavaVMStackOF.java:7)
at JavaVMStackOF.stackLeak(JavaVMStackOF.java:7)
at JavaVMStackOF.stackLeak(JavaVMStackOF.java:7)
at JavaVMStackOF.stackLeak(JavaVMStackOF.java:7)
at JavaVMStackOF.stackLeak(JavaVMStackOF.java:7)
at JavaVMStackOF.stackLeak(JavaVMStackOF.java:7)
at JavaVMStackOF.stackLeak(JavaVMStackOF.java:7)
at JavaVMStackOF.stackLeak(JavaVMStackOF.java:7)
at JavaVMStackOF.stackLeak(JavaVMStackOF.java:7)
at JavaVMStackOF.stackLeak(JavaVMStackOF.java:7)
at JavaVMStackOF.stackLeak(JavaVMStackOF.java:7)
at JavaVMStackOF.stackLeak(JavaVMStackOF.java:7)
at JavaVMStackOF.stackLeak(JavaVMStackOF.java:7)
at JavaVMStackOF.stackLeak(JavaVMStackOF.java:7)
at JavaVMStackOF.stackLeak(JavaVMStackOF.java:7)
at JavaVMStackOF.stackLeak(JavaVMStackOF.java:7)
at JavaVMStackOF.stackLeak(JavaVMStackOF.java:7)
at JavaVMStackOF.stackLeak(JavaVMStackOF.java:7)
at JavaVMStackOF.stackLeak(JavaVMStackOF.java:7)
at JavaVMStackOF.stackLeak(JavaVMStackOF.java:7)