Here at Logilab we find Munin pretty useful. We monitor a lots of machines and a lot of services with it, and it usually gives us pretty useful indicators over time that guide us through to optimizations.

One of the reasons we adopted this technology is it's modular approach with the plugin architecture. And when we realized we could write plugins in python, we knew we'd like it. After years of using it, we're now actually writing plugins for it. Optimizing zope and zeo servers is not an easy task so we're developping plugins to be able to see the difference between before and after changing things.

You check out the project here, and download it from the ftp.

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