JDK內置工具-jstack-查看進程的狀態以及異常診斷

SYNOPSIS-使用方法

jstack [ option ] pid
jstack [ option ] executable core
jstack [ option ] [server-id@]remote-hostname-or-IP

 

PARAMETERS-參數說明

Options are mutually exclusive. Option, if used, should follow immediately after the command name. See OPTIONS.

• pid

• process id for which the stack trace is to be printed. The process must be a Java process. To get a list of Java processes running on a machine, jps may be used

• executable

• Java executable from which the core dump was produced.

• core

• core file for which the stack trace is to be printed.

• remote-hostname-or-IP

• remote debug server's (see jsadebugd) hostname or IP address.

• server-id

• optional unique id, if multiple debug servers are running on the same remote host.

DESCRIPTION

jstack prints Java stack traces of Java threads for a given Java process or core file or a remote debug server. For each Java frame, the full class name, method name, 'bci' (byte code index) and line number, if available, are printed. With the -m option, jstack prints both Java and native frames of all threads along with the 'pc' (program counter). For each native frame, the closest native symbol to 'pc', if available, is printed. C++ mangled names are not demangled. To demangle C++ names, the output of this command may be piped to c++filt. If the given process is running on a 64-bit VM, you may need to specify the -J-d64 option, e.g.:

jstack -J-d64 -m pid #對於在64位的jvm 要加上 -d64

 

NOTE - This utility is unsupported and may or may not be available in future versions of the JDK. In Windows Systems where dbgeng.dll is not present, 'Debugging Tools For Windows' needs to be installed to have these tools working. Also, PATH environment variable should contain the location of jvm.dll used by the target process or the location from which the Crash Dump file was produced.

For example, set PATH=<jdk>\jre\bin\client;%PATH%

OPTIONS-能夠輸入參數

• -F

• Force a stack dump when 'jstack [-l] pid' does not respond.

• -l 能夠查看線程是否被鎖

• Long listing. Prints additional information about locks such as list of owned java.util.concurrent ownable synchronizers.

• -m

• prints mixed mode (both Java and native C/C++ frames) stack trace.

• -h

• prints a help message.

• -help

• prints a help message

SEE ALSO 參考博文：https://dzone.com/articles/how-to-take-thread-dumps-7-options

. jstack

‘jstack’ is an effective command line tool to capture thread dumps. The jstack tool is shipped in JDK_HOME\bin folder. Here is the command that you need to issue to capture thread dump:

jstack -l  <pid> > <file-path>

Where:

pid: is the Process Id of the application, whose thread dump should be captured

file-path: is the file path where thread dump will be written in to.

Example:

jstack -l 37320 > /opt/tmp/threadDump.txt

As per the example thread dump of the process would be generated in /opt/tmp/threadDump.txt file.

Jstack tool is included in JDK since Java 5. If you are running in older version of java, consider using other options

另 jstack 要用和java進程同一個unix帳號下使用

另外能夠參考博文：

http://www.blogjava.net/jzone/articles/303979.html

另外關於每一個線程的狀態所表示的意義能夠參考博文：

http://www.cnblogs.com/zhengyun_ustc/archive/2013/03/18/tda.html

http://gudaoqing.blog.51cto.com/7729345/1332829