Java thread dump | SIGQUIT send dump into tomcat/logs/catalina.out| jstack

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The SIGQUIT signal is useful for stopping a process and telling it to create a core dump file.
OpenJDK / Sun JDK
Use jps -lv to find the Java process ID for issuing kill -QUIT or kill -3.
Be sure the -Xrs JVM option is not being used, as it causes SIGQUIT and SIGWAITING signals to be ignored. Running kill -3 sends a SIGQUIT signal to the JVM, so using this option will cause kill -3 to be ignored. See Java Application launcher.
If using OpenJDK or Sun JDK 1.6 or later, using jstack is an option. This is useful when redirecting standard out to a file is problematic for some reason (e.g. it is not desirable to restart the JVM just to redirect standard out). Execute the following, passing in the Java process ID:
Raw
jstack -l JAVA_PID > jstack.out

When ‘kill -3’ option is used thread dump is sent to the standard error stream. If you are running your application in tomcat, thread dump will be sent into <TOMCAT_HOME>/logs/catalina.outfile.
Note: To my knowledge this option is supported in most flavours of *nix operating systems (Unix, Linux, HP-UX operating systems).



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