jinfo
jinfo(JVM Configuration info)这个命令作用是实时查看和调整虚拟机运行参数。 之前的jps -v口令只能查看到显示指定的参数，如果想要查看未被显示指定的参数的值就要使用jinfo口令
语法
jinfo [ option ] pid
jinfo [ option ] executable core
jinfo [ option ] [ servier-id ] remote-hostname-or-IP
选项
- -flag : 输出指定args参数的值
- -flags : 不需要args参数，输出所有JVM参数的值
- -sysprops : 输出系统属性，等同于System.getProperties()
[root@node1 ~]# jinfo -flags 2656
Attaching to process ID 2656, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 25.201-b09
Non-default VM flags: -XX:CICompilerCount=2 -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=null -XX:InitialHeapSize=268435456 -XX:MaxHeapSize=268435456 -XX:MaxNewSize=89128960 -XX:MinHeapDeltaBytes=524288 -XX:NewSize=89128960 -XX:OldSize=179306496 -XX:OnOutOfMemoryError=null -XX:+UseCompressedClassPointers -XX:+UseCompressedOops -XX:+UseFastUnorderedTimeStamps -XX:+UseParallelGC
Command line: -Xmx1000m -Dhadoop.log.dir=/opt/cloudera/parcels/CDH-5.15.1-1.cdh5.15.1.p0.4/lib/hadoop/logs -Dhadoop.log.file=hadoop.log -Dhadoop.home.dir=/opt/cloudera/parcels/CDH-5.15.1-1.cdh5.15.1.p0.4/lib/hadoop -Dhadoop.id.str= -Dhadoop.root.logger=INFO,console -Djava.library.path=/opt/cloudera/parcels/CDH-5.15.1-1.cdh5.15.1.p0.4/lib/hadoop/lib/native -Dhadoop.policy.file=hadoop-policy.xml -Djava.net.preferIPv4Stack=true -Djava.net.preferIPv4Stack=true -Xms268435456 -Xmx268435456 -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=/tmp/sentry_sentry-SENTRY_SERVER-1041b0846850e06963272caabb1fd69f_pid2656.hprof -XX:OnOutOfMemoryError=/usr/lib64/cmf/service/common/killparent.sh -Dhadoop.security.logger=INFO,NullAppender