package com.jvm.memory; import java.util.ArrayList; import java.util.List; public class HeapOOM { /** * VM 运行时参数 -Xms20m -Xmx20m -XX:+HeapDumpOnOutOfMemoryError * @param args */ public static void main(String[] args) { List<OOMObject> list = new ArrayList<OOMObject>(); while(true){ list.add(new OOMObject()); } } static class OOMObject{ } }
java.lang.OutOfMemoryError: Java heap space
Dumping heap to java_pid2076.hprof ...
Exception in thread "main" Heap dump file created [24777740 bytes in 1.181 secs]
java.lang.OutOfMemoryError: Java heap space
at java.util.Arrays.copyOf(Arrays.java:2760)
at java.util.Arrays.copyOf(Arrays.java:2734)
at java.util.ArrayList.ensureCapacity(ArrayList.java:167)
at java.util.ArrayList.add(ArrayList.java:351)
at com.jvm.memory.HeapOOM.main(HeapOOM.java:14)
java堆用于存储对象实例,我们只要不断的创建对象,达到最大容量限制后,最后就会导致堆内存溢出,
我们如果在系统中出现这种情况就要利用映像分析工具以及对dump转储出来的快照进行分析,看创建这些类是否是有
必须要的。从2个方面检查1:看看对参数是不是设置有问题,是否还可以调大。2:检查是不是某些对象的生命周期过长。
本地方法栈溢出(如果线程请求的栈深度大于虚拟机本身所允许的最大深度,将抛出*Error)
package com.jvm.memory; public class JavaJVMStackOOM { /** * VM args -Xss128k * @param args */ public static void main(String[] args) { JavaJVMStackOOM oom = new JavaJVMStackOOM(); oom.stackLeak(); } private int stackLenth=1; public void stackLeak(){ stackLenth++; stackLeak(); } }
Exception in thread "main" java.lang.*Error
at com.jvm.memory.JavaJVMStackOOM.stackLeak(JavaJVMStackOOM.java:16)
at com.jvm.memory.JavaJVMStackOOM.stackLeak(JavaJVMStackOOM.java:17)
常量池溢出
package com.jvm.memory; import java.util.ArrayList; import java.util.List; public class RuntimeConstantPoolOOM { /** * VM Args -XX:PermSize=10 -XX:MaxPermSize=10 * @param args */ public static void main(String[] args) { List<String> list = new ArrayList<String>(); int i=0; while(true){ list.add(String.valueOf(i++).intern()); } } }
Error occurred during initialization of VM
Too small initial permanent heap