Bjorn Stabell wrote at 2003-10-27 16:46 +0800:

... It's just all things considered, it's very complicated;

- It is, by nature, not easy to debug memory usage of Python applications

Not sure, this is true: There are debug builds of Python such that all Python objects are linked. Thus, you can access all Python objects in use, if this should really be necessary. Memory consumption for Python objects is quite natural if it is sufficient to get the order rather than the precise value. And, to understand why your application runs out of memory, nowadays you need only the order and no longer the precise value.

- It is even harder to debug systems with persistent objects and classes that evolve

It is far more difficult to debug non-deterministic distributed systems. Persistence does not much increase the complexity of debugging.

- It is much harder still to debug big (and complex) systems that are not very well documented

Did you read the available ZODB and Python documentation? If guess, only superficially at most... Many people request documentation but many of them do not read the available parts.

It would be good to have better tools (e.g., DB admin tool) and more docs (which I guess the archived version of this thread is helping with), especially since Zope+ZODB is a platform, not a one-off application.

Then, build them and donate them to the community...

I'm aware Zope is open source and I should contribute code,

Fine, thus I am starting to wait for your contributions... -- Dieter