花生壳免费域名注册网站,国家企业信用信息公示系统网官网,常州网站建设制作,万网注册域名1 jinfo(Configuration Info forJava)作用
实时地查看和调整虚拟机各项参数 2 命令格式
jinfo [options]
参数解释#xff1a;
第一个参数#xff1a;options
no option#xff1a;输出全部的参数和系统属性-flag name#xff1a;输出对应名称的参数-flag [|-]name
第一个参数options
no option输出全部的参数和系统属性-flag name输出对应名称的参数-flag [|-]name开启或者关闭对应名称的参数-flag namevalue设定对应名称的参数-flags输出全部的参数-sysprops输出系统属性 3 命令演示
代码如下
package com.example.demo;import java.io.IOException;/*jinfo:命令jinfo pid描述输出当前 jvm 进程的全部参数和系统属性命令jinfo -flags pid描述输出全部的虚拟机参数命令jinfo -sysprops pid描述输出当前虚拟机进程的全部的系统属性命令jinfo -flag name pid描述使用该命令可以查看指定的 jvm 参数的值如查看当前 jvm 进程是否开启打印 GC 日志jinfo -flag PrintGC pid命令jinfo -flag [|-]name pid描述开启或者关闭对应名称的参数使用 jinfo 可以在不重启虚拟机的情况下可以动态的修改 jvm 的参数。尤其在线上的环境特别有用。jinfo -flag PrintGC pidjinfo -flag PrintGC pidjinfo -flag PrintGC pidjinfo -flag PrintGC pid命令jinfo -flag namevalue pid描述修改指定参数的值。和上面的例子相似但是上面的主要是针对 boolean 值的参数设置的。如果是设置 value值则需要使用 namevalue 的形式jinfo -flag HeapDumpPath pidjinfo -flag HeapDumpPathd:\\dump pidjinfo -flag HeapDumpPath pidjinfo -flag HeapDumpPath pidjinfo -flag HeapDumpPath pid注意jinfo虽然可以在java程序运行时动态地修改虚拟机参数但并不是所有的参数都支持动态修改*/
public class jinfodemo01 {public static void main(String[] args) throws IOException {System.out.println(jinfo);System.in.read();}
}运行后进入命令行工具输入命令。 1命令一
jinfo pid
描述输出当前 jvm 进程的全部参数和系统属性
结果如下
Attaching to process ID 14784, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 25.261-b12
Java System Properties:java.runtime.name Java(TM) SE Runtime Environment
java.vm.version 25.261-b12
sun.boot.library.path C:\Program Files\Java\jdk1.8.0_261\jre\bin
java.vendor.url http://java.oracle.com/
java.vm.vendor Oracle Corporation
path.separator ;
file.encoding.pkg sun.io
java.vm.name Java HotSpot(TM) 64-Bit Server VM
sun.os.patch.level
sun.java.launcher SUN_STANDARD
user.script
user.country CN
user.dir H:\project\jvmtestdemo
java.vm.specification.name Java Virtual Machine Specification
java.runtime.version 1.8.0_261-b12
java.awt.graphicsenv sun.awt.Win32GraphicsEnvironment
os.arch amd64
java.endorsed.dirs C:\Program Files\Java\jdk1.8.0_261\jre\lib\endorsed
line.separator java.io.tmpdir C:\Users\XIONGP~1\AppData\Local\Temp\
java.vm.specification.vendor Oracle Corporation
user.variant
os.name Windows 10
sun.jnu.encoding GBK
java.library.path C:\Program Files\Java\jdk1.8.0_261\bin;C:\WINDOWS\Sun\Java\bin;C:\WINDOWS\system32;C:\WINDOWS;D:\Program Files (x86)\VMware\VMware Workstation\bin\;C:\Program Files (x86)\Common Files\Oracle
\Java\javapath;C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\;C:\Windows\System32\OpenSSH\;C:\Program Files (x86)\NVIDIA Corporation\PhysX\Common;C:\Program
Files\NVIDIA Corporation\NVIDIA NvDLISR;C:\Program Files\Intel\WiFi\bin\;C:\Program Files\Common Files\Intel\WirelessCommon\;E:\maven\apache-maven-3.6.1\bin;E:\maven\apache-maven-3.6.1\bin;D:\Program Files\apac
he-tomcat-9.0.37\lib;D:\Program Files\apache-tomcat-9.0.37\bin;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\WINDOWS\System32\WindowsPowerShell\v1.0\;C:\WINDOWS\System32\OpenSSH\;D:\Program Files\V
isualSVN Server\bin\;C:\ProgramData\chocolatey\bin;D:\Program Files\nodejs\node_global;C:\Program Files\nodejs\;D:\Program Files (x86)\NetSarang\Xshell 7\;E:\hadoop-2.5.2\bin;D:\Program Files\TortoiseSVN\bin;C:
\Program Files\Erlang OTP\bin;H:\Program Files\dev\python\python3.10.4\;H:\Program Files\dev\python\python3.10.4\Scripts;%ANACONDA_HOME%;%ANACONDA_HOME%\Scripts;%ANACONDA_HOME%\Library\bin;%ANACONDA_HOME%\mingw
-w64\bin;D:\Program Files\Git\cmd;D:\Program Files (x86)\NetSarang\Xftp 7\;D:\Program Files\anaconda3;D:\Program Files\anaconda3\Library\mingw-w64\bin;D:\Program Files\anaconda3\Library\usr\bin;D:\Program Files
\anaconda3\Library\bin;D:\Program Files\anaconda3\Scripts;H:\Program Files\dev\python\python3.10.4\Scripts\;H:\Program Files\dev\python\python3.10.4\;D:\Programs Files\Microsoft VS Code\bin;C:\Program Files\Jav
a\jdk1.8.0_261\bin;;.
java.specification.name Java Platform API Specification
java.class.version 52.0
sun.management.compiler HotSpot 64-Bit Tiered Compilers
os.version 10.0
user.home C:\Users\xiongpeng
user.timezone GMT08:00
java.awt.printerjob sun.awt.windows.WPrinterJob
file.encoding UTF-8
java.specification.version 1.8
user.name xiongpeng
java.class.path C:\Program Files\Java\jdk1.8.0_261\jre\lib\charsets.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\deploy.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\ext\access-bridge-64.jar;C:\Program Fil
es\Java\jdk1.8.0_261\jre\lib\ext\cldrdata.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\ext\dnsns.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\ext\jaccess.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\ext\j
fxrt.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\ext\localedata.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\ext\nashorn.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\ext\sunec.jar;C:\Program Files\Java\j
dk1.8.0_261\jre\lib\ext\sunjce_provider.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\ext\sunmscapi.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\ext\sunpkcs11.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\e
xt\zipfs.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\javaws.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\jce.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\jfr.jar;C:\Program Files\Java\jdk1.8.0_261\jre\li
b\jfxswt.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\jsse.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\management-agent.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\plugin.jar;C:\Program Files\Java\jdk1.
8.0_261\jre\lib\resources.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\rt.jar;H:\project\jvmtestdemo\target\classes;D:\Program Files\JetBrains\IntelliJ IDEA 2019.3.2\lib\idea_rt.jar
java.vm.specification.version 1.8
sun.arch.data.model 64
sun.java.command com.example.demo.jinfodemo01
java.home C:\Program Files\Java\jdk1.8.0_261\jre
user.language zh
java.specification.vendor Oracle Corporation
awt.toolkit sun.awt.windows.WToolkit
java.vm.info mixed mode
java.version 1.8.0_261
java.ext.dirs C:\Program Files\Java\jdk1.8.0_261\jre\lib\ext;C:\WINDOWS\Sun\Java\lib\ext
sun.boot.class.path C:\Program Files\Java\jdk1.8.0_261\jre\lib\resources.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\rt.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\sunrsasign.jar;C:\Program Files\Java\j
dk1.8.0_261\jre\lib\jsse.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\jce.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\charsets.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\jfr.jar;C:\Program Files\Java\j
dk1.8.0_261\jre\classes
java.vendor Oracle Corporation
file.separator \
java.vendor.url.bug http://bugreport.sun.com/bugreport/
sun.io.unicode.encoding UnicodeLittle
sun.cpu.endian little
sun.desktop windows
sun.cpu.isalist amd64VM Flags:
Non-default VM flags: -XX:CICompilerCount4 -XX:InitialHeapSize668991488 -XX:MaxHeapSize10697572352 -XX:MaxNewSize3565682688 -XX:MinHeapDeltaBytes524288 -XX:NewSize222822400 -XX:OldSize446169088 -XX:UseC
ompressedClassPointers -XX:UseCompressedOops -XX:UseFastUnorderedTimeStamps -XX:-UseLargePagesIndividualAllocation -XX:UseParallelGC
Command line: -javaagent:D:\Program Files\JetBrains\IntelliJ IDEA 2019.3.2\lib\idea_rt.jar50286:D:\Program Files\JetBrains\IntelliJ IDEA 2019.3.2\bin -Dfile.encodingUTF-82命令二
jinfo -flags pid
描述输出全部的虚拟机参数
结果如下
H:\project\jvmtestdemojinfo -flags 14784
Attaching to process ID 14784, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 25.261-b12
Non-default VM flags: -XX:CICompilerCount4 -XX:InitialHeapSize668991488 -XX:MaxHeapSize10697572352 -XX:MaxNewSize3565682688 -XX:MinHeapDeltaBytes524288 -XX:NewSize222822400 -XX:OldSize446169088 -XX:UseC
ompressedClassPointers -XX:UseCompressedOops -XX:UseFastUnorderedTimeStamps -XX:-UseLargePagesIndividualAllocation -XX:UseParallelGC
Command line: -javaagent:D:\Program Files\JetBrains\IntelliJ IDEA 2019.3.2\lib\idea_rt.jar50286:D:\Program Files\JetBrains\IntelliJ IDEA 2019.3.2\bin -Dfile.encodingUTF-83命令三
jinfo -flag name pid
描述使用该命令可以查看指定的 jvm 参数的值
如查看当前 jvm 进程是否开启打印 GC 日志
H:\project\jvmtestdemojinfo -flag PrintGC 14784
-XX:-PrintGC减号说明该参数没有打开 4命令四
jinfo -flag [|-]name pid
描述开启或者关闭对应名称的参数
使用 jinfo 可以在不重启虚拟机的情况下可以动态的修改 jvm 的参数。尤其在线上的环境特别有用。
例如
jinfo -flag PrintGC pidjinfo -flag PrintGC pidjinfo -flag PrintGC pidjinfo -flag PrintGC pid
如下 5命令五
jinfo -flag namevalue pid
描述修改指定参数的值。
和上面的例子相似但是上面的主要是针对 boolean 值的参数设置的。
如果是设置 value值则需要使用 namevalue 的形式
jinfo -flag HeapDumpPath pid
jinfo -flag HeapDumpPathd:\dump pid
jinfo -flag HeapDumpPath pid
jinfo -flag HeapDumpPath pid
jinfo -flag HeapDumpPath pid
如下 注意jinfo虽然可以在java程序运行时动态地修改虚拟机参数但并不是所有的参数都支持动态修改 6命令六
jinfo -sysprops pid
描述输出当前虚拟机进程的全部的系统属性
H:\project\jvmtestdemojinfo -sysprops 14784
Attaching to process ID 14784, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 25.261-b12
java.runtime.name Java(TM) SE Runtime Environment
java.vm.version 25.261-b12
sun.boot.library.path C:\Program Files\Java\jdk1.8.0_261\jre\bin
java.vendor.url http://java.oracle.com/
java.vm.vendor Oracle Corporation
path.separator ;
file.encoding.pkg sun.io
java.vm.name Java HotSpot(TM) 64-Bit Server VM
sun.os.patch.level
sun.java.launcher SUN_STANDARD
user.script
user.country CN
user.dir H:\project\jvmtestdemo
java.vm.specification.name Java Virtual Machine Specification
java.runtime.version 1.8.0_261-b12
java.awt.graphicsenv sun.awt.Win32GraphicsEnvironment
os.arch amd64
java.endorsed.dirs C:\Program Files\Java\jdk1.8.0_261\jre\lib\endorsed
line.separator java.io.tmpdir C:\Users\XIONGP~1\AppData\Local\Temp\
java.vm.specification.vendor Oracle Corporation
user.variant
os.name Windows 10
sun.jnu.encoding GBK
java.library.path C:\Program Files\Java\jdk1.8.0_261\bin;C:\WINDOWS\Sun\Java\bin;C:\WINDOWS\system32;C:\WINDOWS;D:\Program Files (x86)\VMware\VMware Workstation\bin\;C:\Program Files (x86)\Common Files\Oracle
\Java\javapath;C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\;C:\Windows\System32\OpenSSH\;C:\Program Files (x86)\NVIDIA Corporation\PhysX\Common;C:\Program
Files\NVIDIA Corporation\NVIDIA NvDLISR;C:\Program Files\Intel\WiFi\bin\;C:\Program Files\Common Files\Intel\WirelessCommon\;E:\maven\apache-maven-3.6.1\bin;E:\maven\apache-maven-3.6.1\bin;D:\Program Files\apac
he-tomcat-9.0.37\lib;D:\Program Files\apache-tomcat-9.0.37\bin;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\WINDOWS\System32\WindowsPowerShell\v1.0\;C:\WINDOWS\System32\OpenSSH\;D:\Program Files\V
isualSVN Server\bin\;C:\ProgramData\chocolatey\bin;D:\Program Files\nodejs\node_global;C:\Program Files\nodejs\;D:\Program Files (x86)\NetSarang\Xshell 7\;E:\hadoop-2.5.2\bin;D:\Program Files\TortoiseSVN\bin;C:
\Program Files\Erlang OTP\bin;H:\Program Files\dev\python\python3.10.4\;H:\Program Files\dev\python\python3.10.4\Scripts;%ANACONDA_HOME%;%ANACONDA_HOME%\Scripts;%ANACONDA_HOME%\Library\bin;%ANACONDA_HOME%\mingw
-w64\bin;D:\Program Files\Git\cmd;D:\Program Files (x86)\NetSarang\Xftp 7\;D:\Program Files\anaconda3;D:\Program Files\anaconda3\Library\mingw-w64\bin;D:\Program Files\anaconda3\Library\usr\bin;D:\Program Files
\anaconda3\Library\bin;D:\Program Files\anaconda3\Scripts;H:\Program Files\dev\python\python3.10.4\Scripts\;H:\Program Files\dev\python\python3.10.4\;D:\Programs Files\Microsoft VS Code\bin;C:\Program Files\Jav
a\jdk1.8.0_261\bin;;.
java.specification.name Java Platform API Specification
java.class.version 52.0
sun.management.compiler HotSpot 64-Bit Tiered Compilers
os.version 10.0
user.home C:\Users\xiongpeng
user.timezone GMT08:00
java.awt.printerjob sun.awt.windows.WPrinterJob
file.encoding UTF-8
java.specification.version 1.8
user.name xiongpeng
java.class.path C:\Program Files\Java\jdk1.8.0_261\jre\lib\charsets.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\deploy.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\ext\access-bridge-64.jar;C:\Program Fil
es\Java\jdk1.8.0_261\jre\lib\ext\cldrdata.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\ext\dnsns.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\ext\jaccess.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\ext\j
fxrt.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\ext\localedata.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\ext\nashorn.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\ext\sunec.jar;C:\Program Files\Java\j
dk1.8.0_261\jre\lib\ext\sunjce_provider.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\ext\sunmscapi.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\ext\sunpkcs11.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\e
xt\zipfs.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\javaws.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\jce.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\jfr.jar;C:\Program Files\Java\jdk1.8.0_261\jre\li
b\jfxswt.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\jsse.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\management-agent.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\plugin.jar;C:\Program Files\Java\jdk1.
8.0_261\jre\lib\resources.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\rt.jar;H:\project\jvmtestdemo\target\classes;D:\Program Files\JetBrains\IntelliJ IDEA 2019.3.2\lib\idea_rt.jar
java.vm.specification.version 1.8
sun.arch.data.model 64
sun.java.command com.example.demo.jinfodemo01
java.home C:\Program Files\Java\jdk1.8.0_261\jre
user.language zh
java.specification.vendor Oracle Corporation
awt.toolkit sun.awt.windows.WToolkit
java.vm.info mixed mode
java.version 1.8.0_261
java.ext.dirs C:\Program Files\Java\jdk1.8.0_261\jre\lib\ext;C:\WINDOWS\Sun\Java\lib\ext
sun.boot.class.path C:\Program Files\Java\jdk1.8.0_261\jre\lib\resources.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\rt.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\sunrsasign.jar;C:\Program Files\Java\j
dk1.8.0_261\jre\lib\jsse.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\jce.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\charsets.jar;C:\Program Files\Java\jdk1.8.0_261\jre\lib\jfr.jar;C:\Program Files\Java\j
dk1.8.0_261\jre\classes
java.vendor Oracle Corporation
file.separator \
java.vendor.url.bug http://bugreport.sun.com/bugreport/
sun.io.unicode.encoding UnicodeLittle
sun.cpu.endian little
sun.desktop windows
sun.cpu.isalist amd64
