Support Tomcat JMX Monitoring by default about ngrinder

[Mavlarn]

I think it is necessary. For JVM based target server, heap usage and GC status is really usefule for performance tuning.

[maoyubin]

yes, we could add such as collecting data from target JVM plugins and thereby guiding ngrinder users to dev plugin fit their own biz.

[Mavlarn]

OK. I will implement this feature in 3.3 version.
The issue on JIRA has been created:
http://jira.cubrid.org/browse/NGRINDER-685

[Mavlarn]

Current solution is like this:

1. Create a plugin and extend OnTestSamplingRunnable, which will be triggered during sampleing, including sampling start, sample and end.
2. In this plugin, for every test, will create a directory in test report directory, the directory name is the plugin name. And the monitor data will be saved in file {ip}.data. Currently I just added heap memory usage info and some GC info.
   This plugin will try to get monitor data from all target servers.
3. In report detail page, if the directory with the plugin name exist, it means, there is some monitor plugin enabled. Then in report page, there will be a link for plugin monitor chart for every target server.
4. When you click on the target server under the plugin, it will get the data from server and generate chart. The lables will be in the data from server, it will be used to display as chart header, and also used as a key to get its data from return map.

Then, if user want to add some other kind of monitor data, he can also add it as plugin, and provides the data as this. Then the data can be displayed automatically in page.

[Mavlarn]

On more think, before we have a simple extention for custom monitor data. As below:
http://www.cubrid.org/wiki_ngrinder/entry/how-to-add-custom-monitor-data
But it is not easy to use, and can not display lable in page. It is also not a generic approach.

So, should be remove that part from the code?

[junoyoon]

Nop. It's still providing its value. Leave it.

[junoyoon]

https://sourceforge.net/projects/ngrinder/files/ngrinder-3.3/plugins/

JVM monitoring feature is now provided as plugin.