下面的java代码通过提供一个远程进程的PID来获取java进程的堆转储。该程序使用远程JMX连接转储堆到一个文件。它可能对某人有帮助。不需要jmap。

import java.lang.management.ManagementFactory;
import javax.management.MBeanServerConnection;
import javax.management.remote.JMXConnector;
import javax.management.remote.JMXConnectorFactory;
import javax.management.remote.JMXServiceURL;
import java.lang.reflect.Method;

public class HeapDumper {

public static final String HOST = "192.168.11.177";
public static final String PORT = "1600";
public static final String FILE_NAME = "heapDump.hprof";
public static final String FOLDER_PATH = "C:/";
private static final String HOTSPOT_BEAN_NAME ="com.sun.management:type=HotSpotDiagnostic";

public static void main(String[] args) {
    if(args.length == 0) {
        System.out.println("Enter PID of the Java Process !!!");
        return;
    }
    
    String pidString = args[0];
    int pid = -1;
    if(pidString!=null && pidString.length() > 0) {
        try {
            pid = Integer.parseInt(pidString);
        }
        catch(Exception e) {
            System.out.println("PID is not Valid !!!");
            return;
        }
    }
    boolean isHeapDumpSuccess = false;
    boolean live = true;
    if(pid > 0) {
        MBeanServerConnection beanServerConn = getJMXConnection();
        
        if(beanServerConn!=null) {
            Class clazz = null;
            String dumpFile = FOLDER_PATH+"/"+FILE_NAME;
            try{
                clazz = Class.forName("com.sun.management.HotSpotDiagnosticMXBean");
                Object hotspotMBean = ManagementFactory.newPlatformMXBeanProxy(beanServerConn, HOTSPOT_BEAN_NAME, clazz);
                Method method = clazz.getMethod("dumpHeap", new Class[]{String.class , boolean.class});
                method.setAccessible(true);
                method.invoke(hotspotMBean , new Object[] {dumpFile, new Boolean(live)});
                isHeapDumpSuccess = true;
            }
            catch(Exception e){
                e.printStackTrace();
                isHeapDumpSuccess = false;
            }
            finally{
                clazz = null;
            }
        }
    }
    
    if(isHeapDumpSuccess){
        System.out.println("HeapDump is Success !!!");
    }
    else{
        System.out.println("HeapDump is not Success !!!");
    }
}

private static MBeanServerConnection getJMXConnection() {
    MBeanServerConnection mbeanServerConnection = null;
    String urlString = "service:jmx:rmi:///jndi/rmi://" + HOST + ":" + PORT + "/jmxrmi";
    try {
        JMXServiceURL url = new JMXServiceURL(urlString);
        JMXConnector jmxConnector = JMXConnectorFactory.connect(url);
        mbeanServerConnection = jmxConnector.getMBeanServerConnection();
        System.out.println("JMX Connection is Success for the URL :"+urlString);
    }
    catch(Exception e) {
        System.out.println("JMX Connection Failed !!!");
    }
    return mbeanServerConnection;
}

}

试试下面的一种选择。

对于32位JVM: Jmap -dump:format=b,file=<heap_dump_filename> <pid> 64位JVM(显式引用): jmap -J-d64 -dump:format=b,file=<heap_dump_filename> <pid> 对于64位JVM，在VM参数中使用G1GC算法(仅使用G1GC算法生成活对象堆): jmap -J-d64 -dump:live,format=b,file=<heap_dump_filename> <pid>

相关SE问题:Java堆转储错误与jmap命令:过早的EOF

看看本文中jmap的各种选项

您混淆了两个不同的java转储。Kill -3生成线程转储，而不是堆转储。

线程转储= JVM输出到stdout的每个线程的堆栈跟踪作为文本。 堆转储= JVM进程输出到二进制文件的内存内容。

要在Windows上进行线程转储，如果您的JVM是前台进程，CTRL+BREAK是最简单的方法。如果你在Windows上有一个类似Unix的shell，比如Cygwin或MobaXterm，你可以像在Unix中一样使用kill -3 {pid}。

要在Unix中进行线程转储，如果您的JVM是前台进程，则可以使用CTRL+C或kill -3 {pid}，只要您为JVM获得正确的pid即可。

对于这两种平台，Java都提供了一些有用的实用程序。对于线程转储，jstack {pid}是最好的选择。http://docs.oracle.com/javase/1.5.0/docs/tooldocs/share/jstack.html

Just to finish the dump question out: Heap dumps are not commonly used because they are difficult to interpret. But, they have a lot of useful information in them if you know where/how to look at them. The most common usage is to locate memory leaks. It is a good practice to set the -D on the java command-line so that the heap dump is generated automatically upon an OutOfMemoryError, -XX:+HeapDumpOnOutOfMemoryError But, you can manually trigger a heap dump, also. The most common way is to use the java utility jmap.

注意:此实用程序并非在所有平台上都可用。从JDK 1.6开始，jmap可以在Windows上使用。

命令行示例如下所示

jmap -dump:file=myheap.bin {pid of the JVM}

输出“myheap.bin”不是人类可读的(对我们大多数人来说)，您需要一个工具来分析它。我的首选是MAT. http://www.eclipse.org/mat/

也许jcmd ?

Jcmd实用程序用于向JVM发送诊断命令请求，这些请求对于控制Java Flight records、故障排除以及诊断JVM和Java应用程序非常有用。

The jcmd tool was introduced with Oracle's Java 7 and is particularly useful in troubleshooting issues with JVM applications by using it to identify Java processes' IDs (akin to jps), acquiring heap dumps (akin to jmap), acquiring thread dumps (akin to jstack), viewing virtual machine characteristics such as system properties and command-line flags (akin to jinfo), and acquiring garbage collection statistics (akin to jstat). The jcmd tool has been called "a swiss-army knife for investigating and resolving issues with your JVM application" and a "hidden gem."

下面是调用jcmd时需要使用的过程:

进入jcmd <pid> GC。heap_dump <文件路径> 在这 pid: Java进程Id，将为其捕获堆转储 file-path:打印堆转储的文件路径。

有关获取Java堆转储的更多信息，请参阅本文。

我认为在Linux进程中创建.hprof文件的最好方法是使用jmap命令。例如:jmap -dump:format=b,file=filename。hprof {PID}

您可以使用jmap获取正在运行的任何进程的转储，假设您知道pid。

使用任务管理器或资源监视器获取pid。然后

jmap -dump:format=b,file=heap.hprof <pid>

获取该进程的堆。

对于安装了bash和pgrep并且正在运行单个Java进程的系统，请尝试:

jmap -dump:format=b,file=heap.hprof $(pgrep java)