The most important thing for me is to see what it does to the number of threads and memory consumption. So, anything that captures that “will do” essentially.
If you want to spoil me, you could create (before and after) Java Flight Recorder files, which I can analyze in JDK Mission Control.
You “record” the these using jcmd. There are many options for jcmd, but the gist is:
Find the OH PID:
sudo ps ax | grep java
Once you know the PID, do:
sudo jcmd <PID> JFR.start name=<some name>
You can check ongoing sessions with
sudo jcmd <PID> JFR.check
Once you feel that you’re done, stop the recording with:
sudo jcmd <PID> JFR.stop name=<the same name> filename=<output file>.jfr
These files are too large for the forum, so they must be dumped on some “transfer”/upload site.
This will allow quite detailed information about what’s going on, most of which are more detailed than I actually need. But, some of it might be nice. Again, the number of running threads and heap use are the core pieces of information that I want to compare, so they alone will do - but averages are more useful than snapshots from some arbitrary point in time.