如何查看JVM采用的是哪种GC方法一：使用命令行获取方法二：打印进程信息

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我是靠谱客的博主冷静电源，最近开发中收集的这篇文章主要介绍如何查看JVM采用的是哪种GC方法一：使用命令行获取方法二：打印进程信息，觉得挺不错的，现在分享给大家，希望可以做个参考。

概述

方法一：使用命令行获取

C:Users10255880>java -XX:+PrintCommandLineFlags -version
-XX:InitialHeapSize=136306112 -XX:MaxHeapSize=2180897792 -XX:+PrintCommandLineFl
ags -XX:+UseCompressedClassPointers -XX:+UseCompressedOops -XX:-UseLargePagesInd
ividualAllocation -XX:+UseParallelGC
java version "1.8.0_161"
Java(TM) SE Runtime Environment (build 1.8.0_161-b12)
Java HotSpot(TM) 64-Bit Server VM (build 25.161-b12, mixed mode)

上述结果中的 -XX:+UseParallelGC 表明选择的垃圾收集器为并行收集器。

方法二：打印进程信息

jps：jdk提供的一个查看当前java进程的小工具，可以看做是JavaVirtual Machine Process Status Tool的缩写

C:Program FilesJavajdk1.8.0_161bin>jps
11328 Bootstrap
2800 RemoteMavenServer36
3424 Launcher
5744
6336 Launcher
5540 LoaderMain
9316 Jps
10600
11672 Launcher
4728 KotlinCompileDaemon

jinfo -flags {进程号}：jinfo 命令可以用来查看 Java 进程运行的 JVM 参数,; -flags 可以打印虚拟机标识。
jinfo 命令具体如下：

C:Program FilesJavajdk1.8.0_161bin>jinfo -help
Usage:
    jinfo [option] <pid>
        (to connect to running process)
    jinfo [option] <executable <core>
        (to connect to a core file)
    jinfo [option] [server_id@]<remote server IP or hostname>
        (to connect to remote debug server)

where <option> is one of:
    -flag <name>         to print the value of the named VM flag
    -flag [+|-]<name>    to enable or disable the named VM flag
    -flag <name>=<value> to set the named VM flag to the given value
    -flags               to print VM flags
    -sysprops            to print Java system properties
    <no option>          to print both of the above
    -h | -help           to print this help message

使用jinfo -flags查看所有VM标识

C:Program FilesJavajdk1.8.0_161bin>jinfo -flags  11672
Attaching to process ID 11672, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 25.161-b12
Non-default VM flags: -XX:CICompilerCount=3 -XX:InitialHeapSize=136314880 
-XX:MaxHeapSize=734003200 -XX:MaxNewSize=244318208 -XX:MinHeapDeltaBytes=524288 
-XX:NewSize=45088768 -XX:OldSize=91226112 -XX:+UseCompressedClassPointers 
-XX:+UseCompressedOops -XX:-UseLargePagesIndividualAllocation -XX:+UseParallelGC