周末了，覺(jué)得我還有很多作業(yè)沒(méi)有寫(xiě)，針對(duì)目前大家對(duì)OOM的類(lèi)型不太熟悉，那么我們來(lái)總結(jié)一下各種OOM出現(xiàn)的情況以及解決方法。

　　我們把各種OOM的情況列出來(lái)，然后逐一進(jìn)行代碼編寫(xiě)復(fù)現(xiàn)和提供解決方法。

　　1. 堆溢出-java.lang.OutOfMemoryError: Java heap space。

　　2. 棧溢出-java.lang.OutOfMemorryError。

　　3. 棧溢出-java.lang.StackOverFlowError。

　　4. 元信息溢出-java.lang.OutOfMemoryError: Metaspace。

　　5. 直接內(nèi)存溢出-java.lang.OutOfMemoryError: Direct buffer memory。

　　6. GC超限-java.lang.OutOfMemoryError: GC overhead limit exceeded。

第一種，堆溢出異常，相信大家很常見(jiàn)。即堆內(nèi)對(duì)象不能進(jìn)行回收了，堆內(nèi)存持續(xù)增大，這樣達(dá)到了堆內(nèi)存的最大值，數(shù)據(jù)滿(mǎn)了，所以就出來(lái)了。我們直接放溢出的代碼樣例。我們需要設(shè)置好idea的VM Options: -Xmx100m，這樣我們?cè)O(shè)置為最大堆內(nèi)存，這樣運(yùn)行起來(lái)就很快就出來(lái)錯(cuò)誤了。

package oom;

import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.TimeUnit;

/**
 * @author huangqingshi
 * @Date 2020-07-18
 */
public class HeapOOM {

 static class OOMObject {
 }

 public static void main(String[] args) throws InterruptedException {
 List<OOMObject> list = new ArrayList<>();

 while(true) {
//  TimeUnit.MILLISECONDS.sleep(1);
  list.add(new OOMObject());
 }
 }

}

運(yùn)行的異常如下，代碼直接就出來(lái)我們看到的異常了。

/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/bin/java -Xmx100m -Dfile.encoding=UTF-8 -classpath /Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/charsets.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/deploy.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/cldrdata.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/dnsns.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/jaccess.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/jfxrt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/localedata.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/nashorn.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/sunec.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/sunjce_provider.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/sunpkcs11.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/zipfs.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/javaws.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/jce.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/jfr.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/jfxswt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/jsse.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/management-agent.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/plugin.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/resources.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/rt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/ant-javafx.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/dt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/javafx-mx.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/jconsole.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/packager.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/sa-jdi.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/tools.jar:/Users/huangqingshi/Downloads/flink-project/target/classes:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-java/1.7.2/flink-java-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-core/1.7.2/flink-core-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-annotations/1.7.2/flink-annotations-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-metrics-core/1.7.2/flink-metrics-core-1.7.2.jar:/Users/huangqingshi/.m2/repository/com/esotericsoftware/kryo/kryo/2.24.0/kryo-2.24.0.jar:/Users/huangqingshi/.m2/repository/com/esotericsoftware/minlog/minlog/1.2/minlog-1.2.jar:/Users/huangqingshi/.m2/repository/org/objenesis/objenesis/2.1/objenesis-2.1.jar:/Users/huangqingshi/.m2/repository/commons-collections/commons-collections/3.2.2/commons-collections-3.2.2.jar:/Users/huangqingshi/.m2/repository/org/apache/commons/commons-compress/1.18/commons-compress-1.18.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-shaded-asm/5.0.4-5.0/flink-shaded-asm-5.0.4-5.0.jar:/Users/huangqingshi/.m2/repository/org/apache/commons/commons-lang3/3.3.2/commons-lang3-3.3.2.jar:/Users/huangqingshi/.m2/repository/org/apache/commons/commons-math3/3.5/commons-math3-3.5.jar:/Users/huangqingshi/.m2/repository/org/slf4j/slf4j-api/1.7.15/slf4j-api-1.7.15.jar:/Users/huangqingshi/.m2/repository/com/google/code/findbugs/jsr305/1.3.9/jsr305-1.3.9.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/force-shading/1.7.2/force-shading-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-streaming-java_2.11/1.7.2/flink-streaming-java_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-runtime_2.11/1.7.2/flink-runtime_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-queryable-state-client-java_2.11/1.7.2/flink-queryable-state-client-java_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-hadoop-fs/1.7.2/flink-hadoop-fs-1.7.2.jar:/Users/huangqingshi/.m2/repository/commons-io/commons-io/2.4/commons-io-2.4.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-shaded-netty/4.1.24.Final-5.0/flink-shaded-netty-4.1.24.Final-5.0.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-shaded-jackson/2.7.9-5.0/flink-shaded-jackson-2.7.9-5.0.jar:/Users/huangqingshi/.m2/repository/commons-cli/commons-cli/1.3.1/commons-cli-1.3.1.jar:/Users/huangqingshi/.m2/repository/org/javassist/javassist/3.19.0-GA/javassist-3.19.0-GA.jar:/Users/huangqingshi/.m2/repository/org/scala-lang/scala-library/2.11.12/scala-library-2.11.12.jar:/Users/huangqingshi/.m2/repository/com/typesafe/akka/akka-actor_2.11/2.4.20/akka-actor_2.11-2.4.20.jar:/Users/huangqingshi/.m2/repository/com/typesafe/config/1.3.0/config-1.3.0.jar:/Users/huangqingshi/.m2/repository/org/scala-lang/modules/scala-java8-compat_2.11/0.7.0/scala-java8-compat_2.11-0.7.0.jar:/Users/huangqingshi/.m2/repository/com/typesafe/akka/akka-stream_2.11/2.4.20/akka-stream_2.11-2.4.20.jar:/Users/huangqingshi/.m2/repository/org/reactivestreams/reactive-streams/1.0.0/reactive-streams-1.0.0.jar:/Users/huangqingshi/.m2/repository/com/typesafe/ssl-config-core_2.11/0.2.1/ssl-config-core_2.11-0.2.1.jar:/Users/huangqingshi/.m2/repository/org/scala-lang/modules/scala-parser-combinators_2.11/1.0.4/scala-parser-combinators_2.11-1.0.4.jar:/Users/huangqingshi/.m2/repository/com/typesafe/akka/akka-protobuf_2.11/2.4.20/akka-protobuf_2.11-2.4.20.jar:/Users/huangqingshi/.m2/repository/com/typesafe/akka/akka-slf4j_2.11/2.4.20/akka-slf4j_2.11-2.4.20.jar:/Users/huangqingshi/.m2/repository/org/clapper/grizzled-slf4j_2.11/1.3.2/grizzled-slf4j_2.11-1.3.2.jar:/Users/huangqingshi/.m2/repository/com/github/scopt/scopt_2.11/3.5.0/scopt_2.11-3.5.0.jar:/Users/huangqingshi/.m2/repository/org/xerial/snappy/snappy-java/1.1.4/snappy-java-1.1.4.jar:/Users/huangqingshi/.m2/repository/com/twitter/chill_2.11/0.7.6/chill_2.11-0.7.6.jar:/Users/huangqingshi/.m2/repository/com/twitter/chill-java/0.7.6/chill-java-0.7.6.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-clients_2.11/1.7.2/flink-clients_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-optimizer_2.11/1.7.2/flink-optimizer_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-shaded-guava/18.0-5.0/flink-shaded-guava-18.0-5.0.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-connector-kafka-0.10_2.11/1.7.2/flink-connector-kafka-0.10_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-connector-kafka-0.9_2.11/1.7.2/flink-connector-kafka-0.9_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-connector-kafka-base_2.11/1.7.2/flink-connector-kafka-base_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/kafka/kafka-clients/0.10.2.1/kafka-clients-0.10.2.1.jar:/Users/huangqingshi/.m2/repository/net/jpountz/lz4/lz4/1.3.0/lz4-1.3.0.jar:/Users/huangqingshi/.m2/repository/org/slf4j/slf4j-log4j12/1.7.7/slf4j-log4j12-1.7.7.jar:/Users/huangqingshi/.m2/repository/log4j/log4j/1.2.17/log4j-1.2.17.jar:/Users/huangqingshi/.m2/repository/com/alibaba/fastjson/1.2.62/fastjson-1.2.62.jar:/Users/huangqingshi/.m2/repository/com/google/guava/guava/28.1-jre/guava-28.1-jre.jar:/Users/huangqingshi/.m2/repository/com/google/guava/failureaccess/1.0.1/failureaccess-1.0.1.jar:/Users/huangqingshi/.m2/repository/com/google/guava/listenablefuture/9999.0-empty-to-avoid-conflict-with-guava/listenablefuture-9999.0-empty-to-avoid-conflict-with-guava.jar:/Users/huangqingshi/.m2/repository/org/checkerframework/checker-qual/2.8.1/checker-qual-2.8.1.jar:/Users/huangqingshi/.m2/repository/com/google/errorprone/error_prone_annotations/2.3.2/error_prone_annotations-2.3.2.jar:/Users/huangqingshi/.m2/repository/com/google/j2objc/j2objc-annotations/1.3/j2objc-annotations-1.3.jar:/Users/huangqingshi/.m2/repository/org/codehaus/mojo/animal-sniffer-annotations/1.18/animal-sniffer-annotations-1.18.jar:/Users/huangqingshi/.m2/repository/redis/clients/jedis/3.1.0/jedis-3.1.0.jar:/Users/huangqingshi/.m2/repository/org/apache/commons/commons-pool2/2.6.2/commons-pool2-2.6.2.jar:/Users/huangqingshi/.m2/repository/mysql/mysql-connector-java/8.0.16/mysql-connector-java-8.0.16.jar:/Users/huangqingshi/.m2/repository/com/google/protobuf/protobuf-java/3.6.1/protobuf-java-3.6.1.jar:/Users/huangqingshi/.m2/repository/com/alibaba/druid/1.1.20/druid-1.1.20.jar oom.HeapOOM
Exception in thread "main" java.lang.OutOfMemoryError: Java heap space
    at java.util.Arrays.copyOf(Arrays.java:3210)
    at java.util.Arrays.copyOf(Arrays.java:3181)
    at java.util.ArrayList.grow(ArrayList.java:261)
    at java.util.ArrayList.ensureExplicitCapacity(ArrayList.java:235)
    at java.util.ArrayList.ensureCapacityInternal(ArrayList.java:227)
    at java.util.ArrayList.add(ArrayList.java:458)
    at oom.HeapOOM.main(HeapOOM.java:21)

Process finished with exit code 1

細(xì)心的同學(xué)可以發(fā)現(xiàn)我在里邊設(shè)置了一個(gè)休眠，目的是我們看一下堆內(nèi)存的結(jié)構(gòu)和數(shù)據(jù)圖。我們將休眠代碼打開(kāi)，然后打開(kāi)JDK自帶的jconsole命令，連接上之后我們看一下概覽圖，通過(guò)下圖我們發(fā)現(xiàn)堆內(nèi)存持續(xù)不斷的增長(zhǎng)。

我們打開(kāi)內(nèi)存界面，看一下內(nèi)存，然后點(diǎn)一下GC按鈕，這個(gè)時(shí)候會(huì)有一些類(lèi)進(jìn)行回收，但是還是會(huì)繼續(xù)增長(zhǎng)，看一下下面的圖。

點(diǎn)開(kāi)信息標(biāo)簽看一下。經(jīng)過(guò)幾次GC回收之后，類(lèi)的數(shù)據(jù)量還是變化不大，說(shuō)明沒(méi)有進(jìn)行回收。

以上這種情況的解決方法就是找到問(wèn)題點(diǎn)，分析哪個(gè)地方是否存儲(chǔ)了大量類(lèi)沒(méi)有被回收的情況，通過(guò)JMAP命令將線(xiàn)上的堆內(nèi)存導(dǎo)出來(lái)后進(jìn)行分析。

第二種情況，我們看一下棧溢出的情況，“上菜”，下面的代碼就是無(wú)限的創(chuàng)建線(xiàn)程，直到?jīng)]法再創(chuàng)建線(xiàn)程。

package oom;

import java.util.concurrent.TimeUnit;

/**
 * @author huangqingshi
 * @Date 2020-07-18
 */
public class StackOOM {

 public static void infiniteRun() {
  while(true) {
   Thread thread = new Thread(() -> {

    while (true) {
     try {
      TimeUnit.HOURS.sleep(1);
     } catch (InterruptedException e) {
      e.printStackTrace();
     }
    }

   });
   thread.start();
  }
 }

 public static void main(String[] args) {
  infiniteRun();
 }

}

拋出來(lái)的異常如下，如果真的需要?jiǎng)?chuàng)建線(xiàn)程，我們需要調(diào)整幀棧的大小-Xss512k，默認(rèn)幀棧大小為1M，如果設(shè)置小了，可以創(chuàng)建更多線(xiàn)程。

/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/bin/java -Xss512k -Dfile.encoding=UTF-8 -classpath /Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/charsets.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/deploy.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/cldrdata.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/dnsns.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/jaccess.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/jfxrt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/localedata.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/nashorn.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/sunec.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/sunjce_provider.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/sunpkcs11.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/zipfs.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/javaws.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/jce.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/jfr.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/jfxswt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/jsse.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/management-agent.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/plugin.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/resources.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/rt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/ant-javafx.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/dt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/javafx-mx.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/jconsole.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/packager.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/sa-jdi.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/tools.jar:/Users/huangqingshi/Downloads/flink-project/target/classes:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-java/1.7.2/flink-java-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-core/1.7.2/flink-core-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-annotations/1.7.2/flink-annotations-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-metrics-core/1.7.2/flink-metrics-core-1.7.2.jar:/Users/huangqingshi/.m2/repository/com/esotericsoftware/kryo/kryo/2.24.0/kryo-2.24.0.jar:/Users/huangqingshi/.m2/repository/com/esotericsoftware/minlog/minlog/1.2/minlog-1.2.jar:/Users/huangqingshi/.m2/repository/org/objenesis/objenesis/2.1/objenesis-2.1.jar:/Users/huangqingshi/.m2/repository/commons-collections/commons-collections/3.2.2/commons-collections-3.2.2.jar:/Users/huangqingshi/.m2/repository/org/apache/commons/commons-compress/1.18/commons-compress-1.18.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-shaded-asm/5.0.4-5.0/flink-shaded-asm-5.0.4-5.0.jar:/Users/huangqingshi/.m2/repository/org/apache/commons/commons-lang3/3.3.2/commons-lang3-3.3.2.jar:/Users/huangqingshi/.m2/repository/org/apache/commons/commons-math3/3.5/commons-math3-3.5.jar:/Users/huangqingshi/.m2/repository/org/slf4j/slf4j-api/1.7.15/slf4j-api-1.7.15.jar:/Users/huangqingshi/.m2/repository/com/google/code/findbugs/jsr305/1.3.9/jsr305-1.3.9.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/force-shading/1.7.2/force-shading-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-streaming-java_2.11/1.7.2/flink-streaming-java_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-runtime_2.11/1.7.2/flink-runtime_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-queryable-state-client-java_2.11/1.7.2/flink-queryable-state-client-java_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-hadoop-fs/1.7.2/flink-hadoop-fs-1.7.2.jar:/Users/huangqingshi/.m2/repository/commons-io/commons-io/2.4/commons-io-2.4.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-shaded-netty/4.1.24.Final-5.0/flink-shaded-netty-4.1.24.Final-5.0.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-shaded-jackson/2.7.9-5.0/flink-shaded-jackson-2.7.9-5.0.jar:/Users/huangqingshi/.m2/repository/commons-cli/commons-cli/1.3.1/commons-cli-1.3.1.jar:/Users/huangqingshi/.m2/repository/org/javassist/javassist/3.19.0-GA/javassist-3.19.0-GA.jar:/Users/huangqingshi/.m2/repository/org/scala-lang/scala-library/2.11.12/scala-library-2.11.12.jar:/Users/huangqingshi/.m2/repository/com/typesafe/akka/akka-actor_2.11/2.4.20/akka-actor_2.11-2.4.20.jar:/Users/huangqingshi/.m2/repository/com/typesafe/config/1.3.0/config-1.3.0.jar:/Users/huangqingshi/.m2/repository/org/scala-lang/modules/scala-java8-compat_2.11/0.7.0/scala-java8-compat_2.11-0.7.0.jar:/Users/huangqingshi/.m2/repository/com/typesafe/akka/akka-stream_2.11/2.4.20/akka-stream_2.11-2.4.20.jar:/Users/huangqingshi/.m2/repository/org/reactivestreams/reactive-streams/1.0.0/reactive-streams-1.0.0.jar:/Users/huangqingshi/.m2/repository/com/typesafe/ssl-config-core_2.11/0.2.1/ssl-config-core_2.11-0.2.1.jar:/Users/huangqingshi/.m2/repository/org/scala-lang/modules/scala-parser-combinators_2.11/1.0.4/scala-parser-combinators_2.11-1.0.4.jar:/Users/huangqingshi/.m2/repository/com/typesafe/akka/akka-protobuf_2.11/2.4.20/akka-protobuf_2.11-2.4.20.jar:/Users/huangqingshi/.m2/repository/com/typesafe/akka/akka-slf4j_2.11/2.4.20/akka-slf4j_2.11-2.4.20.jar:/Users/huangqingshi/.m2/repository/org/clapper/grizzled-slf4j_2.11/1.3.2/grizzled-slf4j_2.11-1.3.2.jar:/Users/huangqingshi/.m2/repository/com/github/scopt/scopt_2.11/3.5.0/scopt_2.11-3.5.0.jar:/Users/huangqingshi/.m2/repository/org/xerial/snappy/snappy-java/1.1.4/snappy-java-1.1.4.jar:/Users/huangqingshi/.m2/repository/com/twitter/chill_2.11/0.7.6/chill_2.11-0.7.6.jar:/Users/huangqingshi/.m2/repository/com/twitter/chill-java/0.7.6/chill-java-0.7.6.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-clients_2.11/1.7.2/flink-clients_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-optimizer_2.11/1.7.2/flink-optimizer_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-shaded-guava/18.0-5.0/flink-shaded-guava-18.0-5.0.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-connector-kafka-0.10_2.11/1.7.2/flink-connector-kafka-0.10_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-connector-kafka-0.9_2.11/1.7.2/flink-connector-kafka-0.9_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-connector-kafka-base_2.11/1.7.2/flink-connector-kafka-base_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/kafka/kafka-clients/0.10.2.1/kafka-clients-0.10.2.1.jar:/Users/huangqingshi/.m2/repository/net/jpountz/lz4/lz4/1.3.0/lz4-1.3.0.jar:/Users/huangqingshi/.m2/repository/org/slf4j/slf4j-log4j12/1.7.7/slf4j-log4j12-1.7.7.jar:/Users/huangqingshi/.m2/repository/log4j/log4j/1.2.17/log4j-1.2.17.jar:/Users/huangqingshi/.m2/repository/com/alibaba/fastjson/1.2.62/fastjson-1.2.62.jar:/Users/huangqingshi/.m2/repository/com/google/guava/guava/28.1-jre/guava-28.1-jre.jar:/Users/huangqingshi/.m2/repository/com/google/guava/failureaccess/1.0.1/failureaccess-1.0.1.jar:/Users/huangqingshi/.m2/repository/com/google/guava/listenablefuture/9999.0-empty-to-avoid-conflict-with-guava/listenablefuture-9999.0-empty-to-avoid-conflict-with-guava.jar:/Users/huangqingshi/.m2/repository/org/checkerframework/checker-qual/2.8.1/checker-qual-2.8.1.jar:/Users/huangqingshi/.m2/repository/com/google/errorprone/error_prone_annotations/2.3.2/error_prone_annotations-2.3.2.jar:/Users/huangqingshi/.m2/repository/com/google/j2objc/j2objc-annotations/1.3/j2objc-annotations-1.3.jar:/Users/huangqingshi/.m2/repository/org/codehaus/mojo/animal-sniffer-annotations/1.18/animal-sniffer-annotations-1.18.jar:/Users/huangqingshi/.m2/repository/redis/clients/jedis/3.1.0/jedis-3.1.0.jar:/Users/huangqingshi/.m2/repository/org/apache/commons/commons-pool2/2.6.2/commons-pool2-2.6.2.jar:/Users/huangqingshi/.m2/repository/mysql/mysql-connector-java/8.0.16/mysql-connector-java-8.0.16.jar:/Users/huangqingshi/.m2/repository/com/google/protobuf/protobuf-java/3.6.1/protobuf-java-3.6.1.jar:/Users/huangqingshi/.m2/repository/com/alibaba/druid/1.1.20/druid-1.1.20.jar oom.StackOOM
Exception in thread "main" java.lang.OutOfMemoryError: unable to create new native thread
    at java.lang.Thread.start0(Native Method)
    at java.lang.Thread.start(Thread.java:717)
    at oom.StackOOM.infiniteRun(StackOOM.java:24)
    at oom.StackOOM.main(StackOOM.java:29)

Process finished with exit code 130 (interrupted by signal 2: SIGINT)

以上這種情況是幀棧不夠用了，如果出現(xiàn)了這種情況，我們需要了解什么地方創(chuàng)建了很多線(xiàn)程，線(xiàn)上程序需要用jstack命令，將當(dāng)前線(xiàn)程的狀態(tài)導(dǎo)出來(lái)放到文件里邊，然后將文件上傳到fastthread.io網(wǎng)站上進(jìn)行分析。

第三種情況，我們看一下棧溢出的另一種情況，這就是棧的StackOverFlow的情況。下面就是一個(gè)死循環(huán)遞歸調(diào)用。

package oom;

/**
 * @author huangqingshi
 * @Date 2020-07-18
 */
public class StackOFE {

  public static void stackOverFlowErrorMethod() {
    stackOverFlowErrorMethod();
  }

  public static void main(String[] args) {
    stackOverFlowErrorMethod();
  }

}

運(yùn)行之后出現(xiàn)的錯(cuò)誤如下，程序每次遞歸的時(shí)候，程序會(huì)把數(shù)據(jù)結(jié)果壓入棧，包括里邊的指針等，這個(gè)時(shí)候就需要幀棧大一些才能承受住更多的遞歸調(diào)用。通過(guò)-Xss進(jìn)行設(shè)置，上邊的例子需要設(shè)置小一些，以分配更多的幀棧，這次是一個(gè)幀棧需要記錄程序數(shù)據(jù)，所以需要更大的值。

/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/bin/java -Xss2m -Dfile.encoding=UTF-8 -classpath /Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/charsets.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/deploy.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/cldrdata.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/dnsns.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/jaccess.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/jfxrt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/localedata.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/nashorn.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/sunec.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/sunjce_provider.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/sunpkcs11.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/zipfs.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/javaws.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/jce.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/jfr.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/jfxswt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/jsse.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/management-agent.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/plugin.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/resources.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/rt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/ant-javafx.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/dt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/javafx-mx.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/jconsole.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/packager.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/sa-jdi.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/tools.jar:/Users/huangqingshi/Downloads/flink-project/target/classes:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-java/1.7.2/flink-java-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-core/1.7.2/flink-core-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-annotations/1.7.2/flink-annotations-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-metrics-core/1.7.2/flink-metrics-core-1.7.2.jar:/Users/huangqingshi/.m2/repository/com/esotericsoftware/kryo/kryo/2.24.0/kryo-2.24.0.jar:/Users/huangqingshi/.m2/repository/com/esotericsoftware/minlog/minlog/1.2/minlog-1.2.jar:/Users/huangqingshi/.m2/repository/org/objenesis/objenesis/2.1/objenesis-2.1.jar:/Users/huangqingshi/.m2/repository/commons-collections/commons-collections/3.2.2/commons-collections-3.2.2.jar:/Users/huangqingshi/.m2/repository/org/apache/commons/commons-compress/1.18/commons-compress-1.18.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-shaded-asm/5.0.4-5.0/flink-shaded-asm-5.0.4-5.0.jar:/Users/huangqingshi/.m2/repository/org/apache/commons/commons-lang3/3.3.2/commons-lang3-3.3.2.jar:/Users/huangqingshi/.m2/repository/org/apache/commons/commons-math3/3.5/commons-math3-3.5.jar:/Users/huangqingshi/.m2/repository/org/slf4j/slf4j-api/1.7.15/slf4j-api-1.7.15.jar:/Users/huangqingshi/.m2/repository/com/google/code/findbugs/jsr305/1.3.9/jsr305-1.3.9.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/force-shading/1.7.2/force-shading-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-streaming-java_2.11/1.7.2/flink-streaming-java_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-runtime_2.11/1.7.2/flink-runtime_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-queryable-state-client-java_2.11/1.7.2/flink-queryable-state-client-java_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-hadoop-fs/1.7.2/flink-hadoop-fs-1.7.2.jar:/Users/huangqingshi/.m2/repository/commons-io/commons-io/2.4/commons-io-2.4.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-shaded-netty/4.1.24.Final-5.0/flink-shaded-netty-4.1.24.Final-5.0.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-shaded-jackson/2.7.9-5.0/flink-shaded-jackson-2.7.9-5.0.jar:/Users/huangqingshi/.m2/repository/commons-cli/commons-cli/1.3.1/commons-cli-1.3.1.jar:/Users/huangqingshi/.m2/repository/org/javassist/javassist/3.19.0-GA/javassist-3.19.0-GA.jar:/Users/huangqingshi/.m2/repository/org/scala-lang/scala-library/2.11.12/scala-library-2.11.12.jar:/Users/huangqingshi/.m2/repository/com/typesafe/akka/akka-actor_2.11/2.4.20/akka-actor_2.11-2.4.20.jar:/Users/huangqingshi/.m2/repository/com/typesafe/config/1.3.0/config-1.3.0.jar:/Users/huangqingshi/.m2/repository/org/scala-lang/modules/scala-java8-compat_2.11/0.7.0/scala-java8-compat_2.11-0.7.0.jar:/Users/huangqingshi/.m2/repository/com/typesafe/akka/akka-stream_2.11/2.4.20/akka-stream_2.11-2.4.20.jar:/Users/huangqingshi/.m2/repository/org/reactivestreams/reactive-streams/1.0.0/reactive-streams-1.0.0.jar:/Users/huangqingshi/.m2/repository/com/typesafe/ssl-config-core_2.11/0.2.1/ssl-config-core_2.11-0.2.1.jar:/Users/huangqingshi/.m2/repository/org/scala-lang/modules/scala-parser-combinators_2.11/1.0.4/scala-parser-combinators_2.11-1.0.4.jar:/Users/huangqingshi/.m2/repository/com/typesafe/akka/akka-protobuf_2.11/2.4.20/akka-protobuf_2.11-2.4.20.jar:/Users/huangqingshi/.m2/repository/com/typesafe/akka/akka-slf4j_2.11/2.4.20/akka-slf4j_2.11-2.4.20.jar:/Users/huangqingshi/.m2/repository/org/clapper/grizzled-slf4j_2.11/1.3.2/grizzled-slf4j_2.11-1.3.2.jar:/Users/huangqingshi/.m2/repository/com/github/scopt/scopt_2.11/3.5.0/scopt_2.11-3.5.0.jar:/Users/huangqingshi/.m2/repository/org/xerial/snappy/snappy-java/1.1.4/snappy-java-1.1.4.jar:/Users/huangqingshi/.m2/repository/com/twitter/chill_2.11/0.7.6/chill_2.11-0.7.6.jar:/Users/huangqingshi/.m2/repository/com/twitter/chill-java/0.7.6/chill-java-0.7.6.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-clients_2.11/1.7.2/flink-clients_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-optimizer_2.11/1.7.2/flink-optimizer_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-shaded-guava/18.0-5.0/flink-shaded-guava-18.0-5.0.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-connector-kafka-0.10_2.11/1.7.2/flink-connector-kafka-0.10_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-connector-kafka-0.9_2.11/1.7.2/flink-connector-kafka-0.9_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-connector-kafka-base_2.11/1.7.2/flink-connector-kafka-base_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/kafka/kafka-clients/0.10.2.1/kafka-clients-0.10.2.1.jar:/Users/huangqingshi/.m2/repository/net/jpountz/lz4/lz4/1.3.0/lz4-1.3.0.jar:/Users/huangqingshi/.m2/repository/org/slf4j/slf4j-log4j12/1.7.7/slf4j-log4j12-1.7.7.jar:/Users/huangqingshi/.m2/repository/log4j/log4j/1.2.17/log4j-1.2.17.jar:/Users/huangqingshi/.m2/repository/com/alibaba/fastjson/1.2.62/fastjson-1.2.62.jar:/Users/huangqingshi/.m2/repository/com/google/guava/guava/28.1-jre/guava-28.1-jre.jar:/Users/huangqingshi/.m2/repository/com/google/guava/failureaccess/1.0.1/failureaccess-1.0.1.jar:/Users/huangqingshi/.m2/repository/com/google/guava/listenablefuture/9999.0-empty-to-avoid-conflict-with-guava/listenablefuture-9999.0-empty-to-avoid-conflict-with-guava.jar:/Users/huangqingshi/.m2/repository/org/checkerframework/checker-qual/2.8.1/checker-qual-2.8.1.jar:/Users/huangqingshi/.m2/repository/com/google/errorprone/error_prone_annotations/2.3.2/error_prone_annotations-2.3.2.jar:/Users/huangqingshi/.m2/repository/com/google/j2objc/j2objc-annotations/1.3/j2objc-annotations-1.3.jar:/Users/huangqingshi/.m2/repository/org/codehaus/mojo/animal-sniffer-annotations/1.18/animal-sniffer-annotations-1.18.jar:/Users/huangqingshi/.m2/repository/redis/clients/jedis/3.1.0/jedis-3.1.0.jar:/Users/huangqingshi/.m2/repository/org/apache/commons/commons-pool2/2.6.2/commons-pool2-2.6.2.jar:/Users/huangqingshi/.m2/repository/mysql/mysql-connector-java/8.0.16/mysql-connector-java-8.0.16.jar:/Users/huangqingshi/.m2/repository/com/google/protobuf/protobuf-java/3.6.1/protobuf-java-3.6.1.jar:/Users/huangqingshi/.m2/repository/com/alibaba/druid/1.1.20/druid-1.1.20.jar oom.StackOFE
Exception in thread "main" java.lang.StackOverflowError
    at oom.StackOFE.stackOverFlowErrorMethod(StackOFE.java:10)
    at oom.StackOFE.stackOverFlowErrorMethod(StackOFE.java:10)
    at oom.StackOFE.stackOverFlowErrorMethod(StackOFE.java:10)
    at oom.StackOFE.stackOverFlowErrorMethod(StackOFE.java:10)
    at oom.StackOFE.stackOverFlowErrorMethod(StackOFE.java:10)
    at oom.StackOFE.stackOverFlowErrorMethod(StackOFE.java:10)

遇到上面的情況下，那么就需要通過(guò)jstack將線(xiàn)程數(shù)據(jù)導(dǎo)到文件進(jìn)行分析。找到遞歸的點(diǎn)，如果程序就是需要遞歸的次數(shù)的話(huà)，那么這個(gè)時(shí)候就需要增大幀棧的大小以適應(yīng)程序。

第四種情況，元數(shù)據(jù)區(qū)域溢出，元數(shù)據(jù)區(qū)域也成為方法區(qū)，存儲(chǔ)著類(lèi)的相關(guān)信息，常量池，方法描述符，字段描述符，運(yùn)行時(shí)產(chǎn)生大量的類(lèi)就會(huì)造成這個(gè)區(qū)域的溢出。我們運(yùn)行的時(shí)候指定一下元數(shù)據(jù)區(qū)域的大小，設(shè)置到idea的VM options里邊：-XX:MetaspaceSize=10M -XX:MaxMetaspaceSize=30M。

package oom;

import net.sf.cglib.proxy.Enhancer;
import net.sf.cglib.proxy.MethodInterceptor;
import net.sf.cglib.proxy.MethodProxy;

import java.lang.reflect.Method;

/**
 * @author huangqingshi
 * @Date 2020-07-18
 */
public class MetaspaceOOM {

  static class OOMObject{}

  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();
    }
  }

}

運(yùn)行的結(jié)果如下，元數(shù)據(jù)信息溢出了。這種情況產(chǎn)生的原因有： 通過(guò)CBLIG大量生成類(lèi)，導(dǎo)致Meta信息滿(mǎn)了；JDK7的時(shí)候使用String.intern()不當(dāng)，會(huì)產(chǎn)生大量常量數(shù)據(jù)；加載大量的jsp以及動(dòng)態(tài)生成jsp文件。我們需要調(diào)整元數(shù)據(jù)空間的大小，如果調(diào)大了之后還出現(xiàn)了這種異常，我們需要分析哪里出現(xiàn)的溢出并fix掉。

/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/bin/java -XX:MetaspaceSize=10M -XX:MaxMetaspaceSize=30M -Dfile.encoding=UTF-8 -classpath /Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/charsets.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/deploy.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/cldrdata.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/dnsns.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/jaccess.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/jfxrt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/localedata.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/nashorn.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/sunec.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/sunjce_provider.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/sunpkcs11.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/zipfs.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/javaws.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/jce.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/jfr.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/jfxswt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/jsse.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/management-agent.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/plugin.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/resources.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/rt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/ant-javafx.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/dt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/javafx-mx.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/jconsole.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/packager.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/sa-jdi.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/tools.jar:/Users/huangqingshi/Downloads/flink-project/target/classes:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-java/1.7.2/flink-java-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-core/1.7.2/flink-core-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-annotations/1.7.2/flink-annotations-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-metrics-core/1.7.2/flink-metrics-core-1.7.2.jar:/Users/huangqingshi/.m2/repository/com/esotericsoftware/kryo/kryo/2.24.0/kryo-2.24.0.jar:/Users/huangqingshi/.m2/repository/com/esotericsoftware/minlog/minlog/1.2/minlog-1.2.jar:/Users/huangqingshi/.m2/repository/org/objenesis/objenesis/2.1/objenesis-2.1.jar:/Users/huangqingshi/.m2/repository/commons-collections/commons-collections/3.2.2/commons-collections-3.2.2.jar:/Users/huangqingshi/.m2/repository/org/apache/commons/commons-compress/1.18/commons-compress-1.18.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-shaded-asm/5.0.4-5.0/flink-shaded-asm-5.0.4-5.0.jar:/Users/huangqingshi/.m2/repository/org/apache/commons/commons-lang3/3.3.2/commons-lang3-3.3.2.jar:/Users/huangqingshi/.m2/repository/org/apache/commons/commons-math3/3.5/commons-math3-3.5.jar:/Users/huangqingshi/.m2/repository/org/slf4j/slf4j-api/1.7.15/slf4j-api-1.7.15.jar:/Users/huangqingshi/.m2/repository/com/google/code/findbugs/jsr305/1.3.9/jsr305-1.3.9.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/force-shading/1.7.2/force-shading-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-streaming-java_2.11/1.7.2/flink-streaming-java_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-runtime_2.11/1.7.2/flink-runtime_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-queryable-state-client-java_2.11/1.7.2/flink-queryable-state-client-java_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-hadoop-fs/1.7.2/flink-hadoop-fs-1.7.2.jar:/Users/huangqingshi/.m2/repository/commons-io/commons-io/2.4/commons-io-2.4.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-shaded-netty/4.1.24.Final-5.0/flink-shaded-netty-4.1.24.Final-5.0.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-shaded-jackson/2.7.9-5.0/flink-shaded-jackson-2.7.9-5.0.jar:/Users/huangqingshi/.m2/repository/commons-cli/commons-cli/1.3.1/commons-cli-1.3.1.jar:/Users/huangqingshi/.m2/repository/org/javassist/javassist/3.19.0-GA/javassist-3.19.0-GA.jar:/Users/huangqingshi/.m2/repository/org/scala-lang/scala-library/2.11.12/scala-library-2.11.12.jar:/Users/huangqingshi/.m2/repository/com/typesafe/akka/akka-actor_2.11/2.4.20/akka-actor_2.11-2.4.20.jar:/Users/huangqingshi/.m2/repository/com/typesafe/config/1.3.0/config-1.3.0.jar:/Users/huangqingshi/.m2/repository/org/scala-lang/modules/scala-java8-compat_2.11/0.7.0/scala-java8-compat_2.11-0.7.0.jar:/Users/huangqingshi/.m2/repository/com/typesafe/akka/akka-stream_2.11/2.4.20/akka-stream_2.11-2.4.20.jar:/Users/huangqingshi/.m2/repository/org/reactivestreams/reactive-streams/1.0.0/reactive-streams-1.0.0.jar:/Users/huangqingshi/.m2/repository/com/typesafe/ssl-config-core_2.11/0.2.1/ssl-config-core_2.11-0.2.1.jar:/Users/huangqingshi/.m2/repository/org/scala-lang/modules/scala-parser-combinators_2.11/1.0.4/scala-parser-combinators_2.11-1.0.4.jar:/Users/huangqingshi/.m2/repository/com/typesafe/akka/akka-protobuf_2.11/2.4.20/akka-protobuf_2.11-2.4.20.jar:/Users/huangqingshi/.m2/repository/com/typesafe/akka/akka-slf4j_2.11/2.4.20/akka-slf4j_2.11-2.4.20.jar:/Users/huangqingshi/.m2/repository/org/clapper/grizzled-slf4j_2.11/1.3.2/grizzled-slf4j_2.11-1.3.2.jar:/Users/huangqingshi/.m2/repository/com/github/scopt/scopt_2.11/3.5.0/scopt_2.11-3.5.0.jar:/Users/huangqingshi/.m2/repository/org/xerial/snappy/snappy-java/1.1.4/snappy-java-1.1.4.jar:/Users/huangqingshi/.m2/repository/com/twitter/chill_2.11/0.7.6/chill_2.11-0.7.6.jar:/Users/huangqingshi/.m2/repository/com/twitter/chill-java/0.7.6/chill-java-0.7.6.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-clients_2.11/1.7.2/flink-clients_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-optimizer_2.11/1.7.2/flink-optimizer_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-shaded-guava/18.0-5.0/flink-shaded-guava-18.0-5.0.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-connector-kafka-0.10_2.11/1.7.2/flink-connector-kafka-0.10_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-connector-kafka-0.9_2.11/1.7.2/flink-connector-kafka-0.9_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-connector-kafka-base_2.11/1.7.2/flink-connector-kafka-base_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/kafka/kafka-clients/0.10.2.1/kafka-clients-0.10.2.1.jar:/Users/huangqingshi/.m2/repository/net/jpountz/lz4/lz4/1.3.0/lz4-1.3.0.jar:/Users/huangqingshi/.m2/repository/org/slf4j/slf4j-log4j12/1.7.7/slf4j-log4j12-1.7.7.jar:/Users/huangqingshi/.m2/repository/log4j/log4j/1.2.17/log4j-1.2.17.jar:/Users/huangqingshi/.m2/repository/com/alibaba/fastjson/1.2.62/fastjson-1.2.62.jar:/Users/huangqingshi/.m2/repository/com/google/guava/guava/28.1-jre/guava-28.1-jre.jar:/Users/huangqingshi/.m2/repository/com/google/guava/failureaccess/1.0.1/failureaccess-1.0.1.jar:/Users/huangqingshi/.m2/repository/com/google/guava/listenablefuture/9999.0-empty-to-avoid-conflict-with-guava/listenablefuture-9999.0-empty-to-avoid-conflict-with-guava.jar:/Users/huangqingshi/.m2/repository/org/checkerframework/checker-qual/2.8.1/checker-qual-2.8.1.jar:/Users/huangqingshi/.m2/repository/com/google/errorprone/error_prone_annotations/2.3.2/error_prone_annotations-2.3.2.jar:/Users/huangqingshi/.m2/repository/com/google/j2objc/j2objc-annotations/1.3/j2objc-annotations-1.3.jar:/Users/huangqingshi/.m2/repository/org/codehaus/mojo/animal-sniffer-annotations/1.18/animal-sniffer-annotations-1.18.jar:/Users/huangqingshi/.m2/repository/redis/clients/jedis/3.1.0/jedis-3.1.0.jar:/Users/huangqingshi/.m2/repository/org/apache/commons/commons-pool2/2.6.2/commons-pool2-2.6.2.jar:/Users/huangqingshi/.m2/repository/mysql/mysql-connector-java/8.0.16/mysql-connector-java-8.0.16.jar:/Users/huangqingshi/.m2/repository/com/google/protobuf/protobuf-java/3.6.1/protobuf-java-3.6.1.jar:/Users/huangqingshi/.m2/repository/com/alibaba/druid/1.1.20/druid-1.1.20.jar:/Users/huangqingshi/.m2/repository/cglib/cglib/3.2.5/cglib-3.2.5.jar:/Users/huangqingshi/.m2/repository/org/ow2/asm/asm/5.2/asm-5.2.jar:/Users/huangqingshi/.m2/repository/org/apache/ant/ant/1.9.6/ant-1.9.6.jar:/Users/huangqingshi/.m2/repository/org/apache/ant/ant-launcher/1.9.6/ant-launcher-1.9.6.jar oom.MetaspaceOOM
Exception in thread "main" java.lang.OutOfMemoryError: Metaspace
    at net.sf.cglib.core.AbstractClassGenerator.generate(AbstractClassGenerator.java:345)
    at net.sf.cglib.proxy.Enhancer.generate(Enhancer.java:492)
    at net.sf.cglib.core.AbstractClassGenerator$ClassLoaderData.get(AbstractClassGenerator.java:114)
    at net.sf.cglib.core.AbstractClassGenerator.create(AbstractClassGenerator.java:291)
    at net.sf.cglib.proxy.Enhancer.createHelper(Enhancer.java:480)
    at net.sf.cglib.proxy.Enhancer.create(Enhancer.java:305)
    at oom.MetaspaceOOM.main(MetaspaceOOM.java:28)

Process finished with exit code 1

第五種情況，直接內(nèi)存溢出，我們除了使用堆內(nèi)存外，我們還可能用直接內(nèi)存，即堆外內(nèi)存。NIO為了提高性能，避免在Java Heap和native Heap中切換，所以使用直接內(nèi)存，默認(rèn)情況下，直接內(nèi)存的大小和對(duì)內(nèi)存大小一致。堆外內(nèi)存不受JVM的限制，但是受制于機(jī)器整體內(nèi)存的大小限制。如下代碼設(shè)置堆最大內(nèi)存為128m，直接內(nèi)存為100m，然后我們每次分配1M放到list里邊。　　

-Xmx128m -XX:MaxDirectMemorySize=100M

package oom;

import java.nio.ByteBuffer;
import java.util.ArrayList;
import java.util.List;

/**
 * @author huangqingshi
 * @Date 2020-07-18
 */
public class DirectBufferOOM {

  public static void main(String[] args) {
    final int _1M = 1024 * 1024 * 1;
    List<ByteBuffer> buffers = new ArrayList<>();
    int count = 1;
    while (true) {
      ByteBuffer byteBuffer = ByteBuffer.allocateDirect(_1M);
      buffers.add(byteBuffer);
      System.out.println(count++);
    }

  }
}

這個(gè)時(shí)候，當(dāng)輸出100次的時(shí)候，下次再分配的時(shí)候會(huì)報(bào)OOM-Direct buffer memory。

/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/bin/java -Xmx128m -XX:MaxDirectMemorySize=100M -Dfile.encoding=UTF-8 -classpath /Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/charsets.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/deploy.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/cldrdata.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/dnsns.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/jaccess.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/jfxrt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/localedata.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/nashorn.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/sunec.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/sunjce_provider.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/sunpkcs11.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/ext/zipfs.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/javaws.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/jce.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/jfr.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/jfxswt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/jsse.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/management-agent.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/plugin.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/resources.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/jre/lib/rt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/ant-javafx.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/dt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/javafx-mx.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/jconsole.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/packager.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/sa-jdi.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/lib/tools.jar:/Users/huangqingshi/Downloads/flink-project/target/classes:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-java/1.7.2/flink-java-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-core/1.7.2/flink-core-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-annotations/1.7.2/flink-annotations-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-metrics-core/1.7.2/flink-metrics-core-1.7.2.jar:/Users/huangqingshi/.m2/repository/com/esotericsoftware/kryo/kryo/2.24.0/kryo-2.24.0.jar:/Users/huangqingshi/.m2/repository/com/esotericsoftware/minlog/minlog/1.2/minlog-1.2.jar:/Users/huangqingshi/.m2/repository/org/objenesis/objenesis/2.1/objenesis-2.1.jar:/Users/huangqingshi/.m2/repository/commons-collections/commons-collections/3.2.2/commons-collections-3.2.2.jar:/Users/huangqingshi/.m2/repository/org/apache/commons/commons-compress/1.18/commons-compress-1.18.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-shaded-asm/5.0.4-5.0/flink-shaded-asm-5.0.4-5.0.jar:/Users/huangqingshi/.m2/repository/org/apache/commons/commons-lang3/3.3.2/commons-lang3-3.3.2.jar:/Users/huangqingshi/.m2/repository/org/apache/commons/commons-math3/3.5/commons-math3-3.5.jar:/Users/huangqingshi/.m2/repository/org/slf4j/slf4j-api/1.7.15/slf4j-api-1.7.15.jar:/Users/huangqingshi/.m2/repository/com/google/code/findbugs/jsr305/1.3.9/jsr305-1.3.9.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/force-shading/1.7.2/force-shading-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-streaming-java_2.11/1.7.2/flink-streaming-java_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-runtime_2.11/1.7.2/flink-runtime_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-queryable-state-client-java_2.11/1.7.2/flink-queryable-state-client-java_2.11-1.7.2.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-hadoop-fs/1.7.2/flink-hadoop-fs-1.7.2.jar:/Users/huangqingshi/.m2/repository/commons-io/commons-io/2.4/commons-io-2.4.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-shaded-netty/4.1.24.Final-5.0/flink-shaded-netty-4.1.24.Final-5.0.jar:/Users/huangqingshi/.m2/repository/org/apache/flink/flink-shaded-jackson/2.7.9-5.0/flink-shaded-jackson-2.7.9-5.0.jar:/Users/huangqingshi/.m2/repository/commons-cli/commons-cli/1.3.1/commons-cli-1.3.1.jar:/Users/huangqingshi/.m2/repository/org/javassist/javassist/3.19.0-GA/javassist-3.19.0-GA.jar:/Users/huangqingshi/.m2/repository/org/scala-lang/scala-library/2.11.12/scala-library-2.11.12.jar:/Users/huangqingshi/.m2/repository/com/type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oom.DirectBufferOOM
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Exception in thread "main" java.lang.OutOfMemoryError: Direct buffer memory
    at java.nio.Bits.reserveMemory(Bits.java:694)
    at java.nio.DirectByteBuffer.<init>(DirectByteBuffer.java:123)
    at java.nio.ByteBuffer.allocateDirect(ByteBuffer.java:311)
    at oom.DirectBufferOOM.main(DirectBufferOOM.java:18)

Process finished with exit code 1

這種情況是我們使用直接內(nèi)存造成溢出，這個(gè)時(shí)候我們需要檢查一下程序里邊是否使用的NIO及NIO，比如Netty，里邊的直接內(nèi)存的配置。

第6種情況，JDK1.6之后新增了一個(gè)錯(cuò)誤類(lèi)型，如果堆內(nèi)存太小的時(shí)候會(huì)報(bào)這個(gè)錯(cuò)誤。如果98%的GC的時(shí)候回收不到2%的時(shí)候會(huì)報(bào)這個(gè)錯(cuò)誤，也就是最小最大內(nèi)存出現(xiàn)了問(wèn)題的時(shí)候會(huì)報(bào)這個(gè)錯(cuò)誤。如果代碼配置了最小最大堆內(nèi)存都為10m。

-Xmx10m -Xms10m

package oom;

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

/**
 * @author huangqingshi
 * @Date 2020-07-18
 */
public class GCOverheadOOM {

  public static void main(String[] args) {
    ExecutorService executor = Executors.newFixedThreadPool(5);
    for (int i = 0; i < Integer.MAX_VALUE; i++) {
      executor.execute(() -> {
        try {
          Thread.sleep(10000);
        } catch (InterruptedException e) {
          //do nothing
        }
      });
    }

  }

}

這個(gè)我們創(chuàng)建了一個(gè)線(xiàn)程池，如果線(xiàn)程池執(zhí)行的時(shí)候如果核心線(xiàn)程處理不過(guò)來(lái)的時(shí)候會(huì)把數(shù)據(jù)放到LinkedBlockingQueue里邊，也就是堆內(nèi)存當(dāng)中。這個(gè)時(shí)候我們需要檢查-Xms -Xmx最小最大堆配置是否合理。再一個(gè)dump出現(xiàn)當(dāng)前內(nèi)存來(lái)分析一下是否使用了大量的循環(huán)或使用大量?jī)?nèi)存代碼。

以上就是我們經(jīng)常遇到的情況，我們需要針對(duì)出現(xiàn)的不行情況進(jìn)行分析和處理。

總結(jié)

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