java-jvm-jinfo 博客分类： java-jvm&性能&原理

jinfo:

1、输出 当前java进程启动的相关配置信息，包括各种各样的jvm参数

2、修改运行时的java 进程的opts

 

 

查看参数：

举例：

sudo jinfo 14855

输出：

 

Attaching to process ID 14855, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 24.45-b08
Java System Properties:

java.runtime.name = Java(TM) SE Runtime Environment
java.vm.version = 24.45-b08
sun.boot.library.path = /home/q/java/jdk1.7.0_45/jre/lib/amd64
shared.loader = 
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
java.util.logging.config.file = /home/q/www/projectA/conf/logging.properties
tomcat.util.buf.StringCache.byte.enabled = true
sun.os.patch.level = unknown
sun.java.launcher = SUN_STANDARD
user.country = US
user.dir = /home/robot.walle
java.vm.specification.name = Java Virtual Machine Specification
java.runtime.version = 1.7.0_45-b18
java.awt.graphicsenv = sun.awt.X11GraphicsEnvironment
os.arch = amd64
java.endorsed.dirs = /home/q/tomcat/endorsed
line.separator = 

java.io.tmpdir = /home/q/www/projectA/temp
java.vm.specification.vendor = Oracle Corporation
java.util.logging.manager = org.apache.juli.ClassLoaderLogManager
java.naming.factory.url.pkgs = org.apache.naming
os.name = Linux
gym.cache = /home/q/www/projectA/cache
sun.jnu.encoding = UTF-8
java.library.path = /usr/java/packages/lib/amd64:/usr/lib64:/lib64:/lib:/usr/lib
sun.nio.ch.bugLevel = 
curator-dont-log-connection-problems = false
java.class.version = 51.0
java.specification.name = Java Platform API Specification
http.keepAlive = false
sun.management.compiler = HotSpot 64-Bit Tiered Compilers
os.version = 2.6.32-358.23.2.el6.x86_64
user.home = /home/tomcat
user.timezone = PRC
catalina.useNaming = true
java.awt.printerjob = sun.print.PSPrinterJob
file.encoding = UTF-8
java.specification.version = 1.7
catalina.home = /home/q/tomcat
user.name = tomcat
java.class.path = /home/q/tomcat/bin/bootstrap.jar:/home/q/tomcat/bin/tomcat-juli.jar
java.naming.factory.initial = org.apache.naming.java.javaURLContextFactory
package.definition = sun.,java.,org.apache.catalina.,org.apache.coyote.,org.apache.tomcat.,org.apache.jasper.
java.vm.specification.version = 1.7
sun.arch.data.model = 64
sun.java.command = org.apache.catalina.startup.Bootstrap start
java.home = /home/q/java/jdk1.7.0_45/jre
user.language = en
java.specification.vendor = Oracle Corporation
awt.toolkit = sun.awt.X11.XToolkit
java.vm.info = mixed mode
java.version = 1.7.0_45
java.ext.dirs = /home/q/java/jdk1.7.0_45/jre/lib/ext:/usr/java/packages/lib/ext
sun.boot.class.path = /home/q/java/jdk1.7.0_45/jre/lib/resources.jar:/home/q/java/jdk1.7.0_45/jre/lib/rt.jar:/home/q/java/jdk1.7.0_45/jre/lib/sunrsasign.jar:/home/q/java/jdk1.7.0_45/jre/lib/jsse.jar:/home/q/java/jdk1.7.0_45/jre/lib/jce.jar:/home/q/java/jdk1.7.0_45/jre/lib/charsets.jar:/home/q/java/jdk1.7.0_45/jre/lib/jfr.jar:/home/q/java/jdk1.7.0_45/jre/classes
server.loader = 
java.vendor = Oracle Corporation
catalina.base = /home/q/www/projectA
file.separator = /
java.vendor.url.bug = http://bugreport.sun.com/bugreport/
common.loader = ${catalina.base}/lib,${catalina.base}/lib/*.jar,${catalina.home}/lib,${catalina.home}/lib/*.jar
sun.io.unicode.encoding = UnicodeLittle
sun.cpu.endian = little
package.access = sun.,org.apache.catalina.,org.apache.coyote.,org.apache.tomcat.,org.apache.jasper.,sun.beans.
sun.cpu.isalist = 

VM Flags:

-Djava.util.logging.config.file=/home/q/www/projectA/conf/logging.properties -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager -Xms7168m -Xmx7168m -Xmn2048m -XX:SurvivorRatio=6 -XX:-OmitStackTraceInFastThrow -XX:+DisableExplicitGC -XX:MaxPermSize=400m -verbose:gc -XX:+PrintGCDateStamps -XX:+PrintGCDetails -Xloggc:/home/q/www/projectA/logs/gc.log -Djava.endorsed.dirs=/home/q/tomcat/endorsed -Dcatalina.base=/home/q/www/projectA -Dcatalina.home=/home/q/tomcat -Djava.io.tmpdir=/home/q/www/projectA/temp

 

 

 查看参数：

   

sudo jinfo -flag MaxPermSize 48892

   输出：

 

   

-XX:MaxPermSize=85983232

 

修改参数：

C:\Users\xinchun.wang> jinfo -flag PrintGCDetails 48892
-XX:-PrintGCDetails

C:\Users\xinchun.wang> jinfo -flag +PrintGCDetails 48892
#无输出
C:\Users\xinchun.wang> jinfo -flag PrintGCDetails 48892
-XX:+PrintGCDetails