使用java自带工具监控jvm运行状态

使用java自带工具监控jvm运行状态

　 1.jps：查看当前运行着的java进程（仿linux下的ps）,显示进程号

　　2. jinfo: 查参数jinfo -flagPermSize 2208(进程号)

jinfo -flag MaxPermSize 2208(进程号) C:\Users\WILL>jinfo Usage: jinfo <option> <pid> (to connect to a running process) 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 -h | -help           to print this help message

　　 3. jconsole 2208

　　用法:

jconsole [ -interval=n ] [ -notile ] [ -pluginpath <path> ] [ -version ] [ connection ...] -interval   将更新间隔时间设置为 n 秒（默认值为 4 秒） -notile     最初不平铺显示窗口（对于两个或更多连接） -pluginpath 指定 jconsole 用于查找插件的路径 -version    输出程序版本 connection = pid || host:port || JMX URL (service:jmx:<protocol>://...) pid       目标进程的进程 ID host      远程主机名或 IP 地址 port      用于远程连接的端口号 -J          对正在运行 jconsole 的 Java 虚拟机指定

　　输入参数

　　 4. jstack  2208列出所有线程，以及线程的运行状态

C:\Users\WILL>jstack Usage: jstack [-l] <pid> (to connect to running process) Options: -l  long listing. Prints additional information about locks -h or -help to print this help message

　 　5. jstat -gcutil 2208 1000(每隔1000毫秒打印一次信息) 10（打印10行）

C:\Users\WILL>jstat invalid argument count Usage: jstat -help|-options jstat -<option> [-t] [-h<lines>] <vmid> [<interval> [<count>]] Definitions: <option>      An option reported by the -options option <vmid>        Virtual Machine Identifier. A vmid takes the following form: <lvmid>[@<hostname>[:<port>]] Where <lvmid> is the local vm identifier for the target Java virtual machine, typically a process id; <hostname> is the name of the host running the target Java virtual machine; and <port> is the port number for the rmiregistry on the target host. See the jvmstat documentation for a more complete description of the Virtual Machine Identifier. <lines>       Number of samples between header lines. <interval>    Sampling interval. The following forms are allowed: <n>["ms"|"s"] Where <n> is an integer and the suffix specifies the units as milliseconds("ms") or seconds("s"). The default units are "ms". <count>       Number of samples to take before terminating. -J<flag>      Pass <flag> directly to the runtime system.

　　C:\Users\WILL>jstat -options

　　-class

　　-compiler

　　-gc

　　-gccapacity

　　-gccause

　　-gcnew

　　-gcnewcapacity

　　-gcold

　　-gcoldcapacity

　　-gcpermcapacity

　　-gcutil

　　-printcompilation

　　 6. jmap把虚拟机里运行着的所有文件都down下来，相当于快照

C:\Users\WILL>jmap Usage: jmap -histo <pid> (to connect to running process and print histogram of java object heap jmap -dump:<dump-options> <pid> (to connect to running process and dump java heap) dump-options: format=b     binary default file=<file>  dump heap to <file> Example:       jmap -dump:format=b,file=heap.bin <pid>

　　 7. jhat 对jmap下来的文件进行分析,多个角度

Usage:  jhat [-stack <bool>] [-refs <bool>] [-port <port>] [-baseline <file>] [- debug <int>] [-version] [-h|-help] <file> -J<flag>          Pass <flag> directly to the runtime system. For example, -J-mx512m to use a maximum heap size of 512MB -stack false:     Turn off tracking object allocation call stack. -refs false:      Turn off tracking of references to objects -port <port>:     Set the port for the HTTP server.  Defaults to 7000 -exclude <file>:  Specify a file that lists data members that should be excluded from the reachableFrom query. -baseline <file>: Specify a baseline object dump.  Objects in both heap dumps with the same ID and same class will be marked as not being "new". -debug <int>:     Set debug level. 0:  No debug output 1:  Debug hprof file parsing 2:  Debug hprof file parsing, no server -version          Report version number -h|-help          Print this help and exit <file>            The file to read For a dump file that contains multiple heap dumps, you may specify which dump in the file by appending "#<number>" to the file name, i.e. "foo.hprof#3". All boolean options default to "true"

　　图片又不能上传。。。就打印出这些帮助参数来，能看懂得了。