jinfo
jinfo -flag CMSInitiatingOccupancyFraction 515
-XX:CMSInitiatingOccupancyFraction=-1
可以打印一些系统属性
jstat
jstat -gcutil 3359
S0 S1 E O M CCS YGC YGCT FGC FGCT GCT
0.00 25.14 40.51 71.72 96.27 94.77 107 1.268 16 0.490 1.757
监控虚拟机的基本状况，内存，gc等情况
jps
-l 输出主类的全名
-v 输出jvm参数
-m 输出传递给main函数的参数
-q 只输出本地虚拟机唯一id（lvmid）
jmap
jhat
The jhat command parses a java heap dump file and launches a webserver.
jhat enables you to browse heap dumps using your favorite webbrowser. jhat
supports pre-designed queries (such as 'show all instances of a known class
"Foo"') as well as OQL (Object Query Language) - a SQL-like query
language to query heap dumps. Help on OQL is available from the OQL help page
shown by jhat. With the default port, OQL help is available at
http://localhost:7000/oqlhelp/
可以看出，是对jmap dump的数据进行分析。
