常見OOM異常分析

java.lang.OutOfMemoryError: Java heap space

package oom;
import java.util.ArrayList;import java.util.List;
/** * JVM配置參數(shù) * -Xms20m    JVM初始分配的內(nèi)存20m * -Xmx20m   JVM最大可用內(nèi)存為20m * -XX:+HeapDumpOnOutOfMemoryError 當(dāng)JVM發(fā)生OOM時(shí)，自動(dòng)生成DUMP文件 * -XX:HeapDumpPath=/Users/weihuaxiao/Desktop/dump/  生成DUMP文件的路徑 */public class HeapOOM {    static class OOMObject {    }    public static void main(String[] args) {        List<OOMObject> list = new ArrayList<OOMObject>();        //在堆中無(wú)限創(chuàng)建對(duì)象        while (true) {            list.add(new OOMObject());        }    }}

Exception in thread "main" java.lang.OutOfMemoryError: Java heap space

package oom;
/** * -Xss2M */public class JavaVMStackOOM {    private void dontStop(){        while(true){
        }    }    public void stackLeakByThread(){        while(true){            Thread thread = new Thread(new Runnable(){                public void run() {                    dontStop();                }            });            thread.start();}    }    public static void main(String[] args) {        JavaVMStackOOM oom = new JavaVMStackOOM();        oom.stackLeakByThread();    }}

Exception in thread "main" java.lang.OutOfMemoryError: unable to create new native thread

  Thread thread = new Thread(new Runnable(){                public void run() {                    dontStop();                }            });

package oom;
import org.springframework.cglib.proxy.Enhancer;import org.springframework.cglib.proxy.MethodInterceptor;import org.springframework.cglib.proxy.MethodProxy;
import java.lang.reflect.Method;
/** *  jdk8以上的話， *  虛擬機(jī)參數(shù)：-XX:MetaspaceSize=10M -XX:MaxMetaspaceSize=10M  */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 {    }}

Caused by: java.lang.OutOfMemoryError: Metaspace

-XX:MetaspaceSize=10M -XX:MaxMetaspaceSize=10M 

  while (true) {  ...   enhancer.setCallback(new MethodInterceptor() {                public Object intercept(Object obj, Method method,                                        Object[] args, MethodProxy proxy) throws Throwable {                    return proxy.invokeSuper(obj, args);                }            });            enhancer.create();  }

package oom;
import java.nio.ByteBuffer;import java.util.concurrent.TimeUnit;
/** * -Xmx256m -XX:MaxDirectMemorySize=100M */public class DirectByteBufferTest {    public static void main(String[] args) throws InterruptedException{        //分配128MB直接內(nèi)存        ByteBuffer bb = ByteBuffer.allocateDirect(1024*1024*128);
        TimeUnit.SECONDS.sleep(10);        System.out.println("ok");    }}

 ByteBuffer bb = ByteBuffer.allocateDirect(1024*1024*128);

package oom;
import java.util.concurrent.ExecutorService;import java.util.concurrent.Executors;
/** * JVm參數(shù) -Xmx8m -Xms8m */public class GCoverheadTest {    public static void main(String[] args) {        ExecutorService executor = Executors.newFixedThreadPool(10);        for (int i = 0; i < Integer.MAX_VALUE; i++) {            executor.execute(() -> {                try {                    Thread.sleep(10000);                } catch (InterruptedException e) {                    //do nothing                }            });        }    }}

java.lang.OutOfMemoryError: Java heap spacejava.lang.OutOfMemoryError: unable to create new native threadjava.lang.OutOfMemoryError: Metaspacejava.lang.OutOfMemoryError: Direct buffer memoryjava.lang.OutOfMemoryError: GC overhead limit exceeded