The DZUG-Tagung (DZUG = german speaking Zope user group) is on in St. Augustin and we just arrived although a little late (due to police actions on some station on the way). I will try to blog a little about this while I am here so expect some posts.
First talk we attended was by Andreas Jung about Profiling Zope. He presented PTProfiles for profiling Page Templates on TALES-Basis and ZopeProfiler by Dieter Maurer.
PTProfiler is not that lowlevel and basically collects data about time and calls of TALES expressions. You install it by instanciating it in the ZMI and activating it. You then make a request and after that you will get a list of all the templates and macros used as well as a list of TALES expressions inside these template with no of calls, time per call and cumulative time.
Some discussion was going on between Andreas and Philipp von Weitershausen whether it still works for Zope2.10 as the TAL engine was replaced by the Zope3 one in this version.
ZopeProfiler by Dieter Maurer is for more lowlevel analyses. You will get a list of Zope calls with number of calls, time per call and cumulative time. The list can be sorted and filtered. For this to use you need to have knowledge about the inner workings of Zope though. So this list contains all templates, images, and management screens.
Another report is the list of the underlying Python method calls. This is even more lowlevel and thus you also need more knowledge to interpret the data.
Be aware that with an enabled Zope Profiler the site will become really slow and thus you should not do that on a production site.
It depends on your use case which is useful to you as sometimes PTProfiler might be sufficient to debug your page templates.