Posted by bhaktimehta
on May 25, 2007 at 1:09 PM PDT
Most of run into bugs where tests "hang". Here are some nice tools and tips I found to obtain and analyze thread dumps.
Most of us run into bugs where tests "hang". Here are some nice tools and
tips I found to obtain and analyze thread dumps. I am sure there may be
other tools so if you know of some good ones feel free to add.
prints Java stack traces of Java threads for a given Java
process or core file or a remote debug server. However jstack is not
available for Windows platforms or on
the Linux platform.
Stacktrace has great features which include
1. Thread dump for Java processes running as a Windows
service (like Tomcat, for example), started with javaw.exe
or embedded inside another process.
dump for any applet running inside any browser (Apple, IBM and Sun JDKs
for Windows and Mac OS X). StackTrace is known to work with IE,
Firefox, Safari and Mozilla.
and many other features..
I usually get the java process id using
Control Break/ kill options
On UNIX platforms you can send a signal to a program by using the
command. This is the quit signal, which is handled by the JVM.
For example, on Solaris you can use the command kill -QUIT
where process_id is the process number
of your Java program.
Alternatively you can enter the key sequence <ctrl>\ in
the window where the Java program was started. Sending this signal
instructs a signal handler in the JVM, to recursively print out all the
information on the threads
and monitors inside the JVM.
To generate a stack trace on Windows platforms, enter the key
sequence <ctrl><break> in the window where
the Java program is running, or click the Close button on the window.
Byron Nevins has also pointed in his
to obtain thread dumps in Glassfish.
This is a great utility I found for analyzing thread dumps.
I especially liked the ability to filter the threads display to be able
to ignore e.g. idle threads.. Also as you can see in Fig 1 The three
pane view is really helpful
Fig 1 : Using TDA to analyze thread dumps