Java –什么是-Xms和-Xmx参数？

你的名字 2023-02-15 05:15 115阅读 0赞

在Java中， `-Xms`设置初始Java堆大小，而`-Xmx`设置最大Java堆大小。

1.一些`java -Xms -Xmx`示例：

# Start with 128MB of memory, and allow the Java process to use up to 1024MB of memory. 
    java -Xms128m -Xmx1024m

# Start with 256MB of memory, and allow the Java process to use up to 4G (4096MB) of memory.
    java -Xms256m -Xmx4g

2.默认的初始和最大Java堆大小是根据这种[人体工程学算法][Link 1]分配的，还请阅读本文– 查找Java堆内存大小

3.如果Java进程超出了`-Xmx`最大Java堆大小，则将引发流行的`java.lang.OutOfMemoryError` 。

4.对于其他选项，请运行此`java -X`

> java -X
    
        -Xbatch           disable background compilation
        -Xbootclasspath/a:<directories and zip/jar files separated by ;>
                          append to end of bootstrap class path
        -Xcheck:jni       perform additional checks for JNI functions
        -Xcomp            forces compilation of methods on first invocation
        -Xdebug           provided for backward compatibility
        -Xdiag            show additional diagnostic messages
        -Xfuture          enable strictest checks, anticipating future default
        -Xint             interpreted mode execution only
        -Xinternalversion
                          displays more detailed JVM version information than the
                          -version option
        -Xloggc:<file>    log GC status to a file with time stamps
        -Xmixed           mixed mode execution (default)
        -Xmn<size>        sets the initial and maximum size (in bytes) of the heap
                          for the young generation (nursery)
        -Xms<size>        set initial Java heap size
        -Xmx<size>        set maximum Java heap size
        -Xnoclassgc       disable class garbage collection
        -Xrs              reduce use of OS signals by Java/VM (see documentation)
        -Xshare:auto      use shared class data if possible (default)
        -Xshare:off       do not attempt to use shared class data
        -Xshare:on        require using shared class data, otherwise fail.
        -XshowSettings    show all settings and continue
        -XshowSettings:all
                          show all settings and continue
        -XshowSettings:locale
                          show all locale related settings and continue
        -XshowSettings:properties
                          show all property settings and continue
        -XshowSettings:vm
                          show all vm related settings and continue
        -XshowSettings:system
                          (Linux Only) show host system or container
                          configuration and continue
        -Xss<size>        set java thread stack size
        -Xverify          sets the mode of the bytecode verifier

## 参考文献 ##

*  [调整Java虚拟机（JVM）][Java_JVM]
 *  [Eclipse -Xms / -Xmx][Eclipse -Xms _ -Xmx]
 *  [人机工程学算法][Link 1]
 *  找出您的Java堆内存大小

标签： [堆大小][Link 2] [Java][] [内存][Link 3]

> 翻译自: [https://mkyong.com/java/java-what-is-xms-and-xmx-parameter/][https_mkyong.com_java_java-what-is-xms-and-xmx-parameter]

[Link 1]: https://www.oracle.com/technetwork/java/ergo5-140223.html
[Java_JVM]: https://docs.oracle.com/cd/E21764_01/web.1111/e13814/jvm_tuning.htm
[Eclipse -Xms _ -Xmx]: https://www.eclipse.org/openj9/docs/xms/
[Link 2]: https://mkyong.com/tag/heap-size/
[Java]: https://mkyong.com/tag/java/
[Link 3]: https://mkyong.com/tag/memory/
[https_mkyong.com_java_java-what-is-xms-and-xmx-parameter]: https://mkyong.com/java/java-what-is-xms-and-xmx-parameter/