java性能监控工具jps-windows
jps
Lists the instrumented Java Virtual Machines (JVMs) on the target system. This command is experimental and unsupported.
Synopsis
jps [ options ] [ hostid ]
options-
Command-line options. See Options.
- hostid
-
The identifier of the host for which the process report should be generated. The
hostid
can include optional components that indicate the communications protocol, port number, and other implementation specific data. See Host Identifier.
Description
The jps
command lists the instrumented Java HotSpot VMs on the target system. The command is limited to reporting information on JVMs for which it has the access permissions.
If the jps
command is run without specifying a hostid
, then it searches for instrumented JVMs on the local host. If started with a hostid
, then it searches for JVMs on the indicated host, using the specified protocol and port. A jstatd
process is assumed to be running on the target host.
The jps
command reports the local JVM identifier, or lvmid
, for each instrumented JVM found on the target system. The lvmid
is typically, but not necessarily, the operating system's process identifier for the JVM process. With no options, jps
lists each Java application's lvmid
followed by the short form of the application's class name or jar file name. The short form of the class name or JAR file name omits the class's package information or the JAR files path information.
The jps
command uses the Java launcher to find the class name and arguments passed to the main method. If the target JVM is started with a custom launcher, then the class or JAR file name and the arguments to the main
method are not available. In this case, the jps
command outputs the string Unknown
for the class name or JAR file name and for the arguments to the main
method.
The list of JVMs produced by the jps
command can be limited by the permissions granted to the principal running the command. The command only lists the JVMs for which the principle has access rights as determined by operating system-specific access control mechanisms.
Options
The jps
command supports a number of options that modify the output of the command. These options are subject to change or removal in the future.
Suppresses the output of the class name, JAR file name, and arguments passed to the main
method, producing only a list of local JVM identifiers.
Displays the arguments passed to the main
method. The output may be null
for embedded JVMs.
Displays the full package name for the application's main
class or the full path name to the application's JAR file.
Displays the arguments passed to the JVM.
-VSuppresses the output of the class name, JAR file name, and arguments passed to the main method, producing only a list of local JVM identifiers.
-Joption
-
Passes
option
to the JVM, where option is one of theoptions
described on the reference page for the Java application launcher. For example,-J-Xms48m
sets the startup memory to 48 MB. Seejava
(1).
Host Identifier
The host identifier, or hostid
is a string that indicates the target system. The syntax of the hostid
string corresponds to the syntax of a URI:
[protocol:][[//]hostname][:port][/servername]
- protocol
-
The communications protocol. If the
protocol
is omitted and ahostname
is not specified, then the default protocol is a platform-specific, optimized, local protocol. If the protocol is omitted and a host name is specified, then the default protocol isrmi
. - hostname
-
A hostname or IP address that indicates the target host. If you omit the
hostname
parameter, then the target host is the local host. - port
-
The default port for communicating with the remote server. If the
hostname
parameter is omitted or theprotocol
parameter specifies an optimized, local protocol, then theport
parameter is ignored. Otherwise, treatment of theport
parameter is implementation specific. For the defaultrmi
protocol, theport
parameter indicates the port number for the rmiregistry on the remote host. If theport
parameter is omitted, and theprotocol
parameter indicatesrmi
, then the default rmiregistry port (1099) is used. - servername
-
The treatment of this parameter depends on the implementation. For the optimized, local protocol, this field is ignored. For the
rmi
protocol, this parameter is a string that represents the name of the RMI remote object on the remote host. See thejstatd
command-n
option for more information.
Output Format
The output of the jps
command follows the following pattern:
lvmid [ [ classname | JARfilename | "Unknown"] [ arg* ] [ jvmarg* ] ]
All output tokens are separated by white space. An arg
value that includes embedded white space introduces ambiguity when attempting to map arguments to their actual positional parameters.
Note: It is recommended that you do not write scripts to parse jps
output because the format might change in future releases. If you write scripts that parse jps
output, then expect to modify them for future releases of this tool.
Examples
This section provides examples of the jps
command.
List the instrumented JVMs on the local host:
jps 18027 Java2Demo.JAR 18032 jps 18005 jstat
The following example lists the instrumented JVMs on a remote host. This example assumes that the jstat
server and either the its internal RMI registry or a separate external rmiregistry process are running on the remote host on the default port (port 1099). It also assumes that the local host has appropriate permissions to access the remote host. This example also includes the -l
option to output the long form of the class names or JAR file names.
jps -l remote.domain 3002 /opt/jdk1.7.0/demo/jfc/Java2D/Java2Demo.JAR 2857 sun.tools.jstatd.jstatd
The following example lists the instrumented JVMs on a remote host with a non-default port for the RMI registry. This example assumes that the jstatd
server, with an internal RMI registry bound to port 2002, is running on the remote host. This example also uses the -m
option to include the arguments passed to the main
method of each of the listed Java applications.
jps -m remote.domain:2002 3002 /opt/jdk1.7.0/demo/jfc/Java2D/Java2Demo.JAR 3102 sun.tools.jstatd.jstatd -p 2002