I never noticed this before today, but apparently RAMCacheManager is sensitive to whether cached items are acquired from the context or from the container. (Zope 2.7.3 but afaict it should behave the same in any recent version). Is that intended behavior or is this a bug? Let's say I have a CMF site at http://foo:8080/TheSite. And a template at /TheSite/portal_skins/custom/template1 which looks in part like like: <p tal:content="context/expensive_script">...</p> Let's say that expensive_script is also in portal_skins/custom and is associated with a RAMCacheManager. Let's say that there are *no* request variables configured for this RAMCacheManager, which would seem to indicate that we consider all calls to expensive_script equivalent regardless of the request. If I visit http://foo:8080/TheSite/page1, which page makes use of this template, and I reload several times, and look at the RAMCacheManager statistics view, I see several hits for /TheSite/expensive_script. Every time I reload, the hit count goes up by one. So far so good. But if I then visit another page, http://foo:8080/TheSite/page2, which uses the same template, I get a miss and the entry count goes up by one. Reloading then gives me a hit, presumably from the new entry. If I browse around the site, the entry count increments for every new page I hit. Remember that I have nothing configured in the "REQUEST Variables" field. So the script should be the same regardless of the request right? This was puzzling me until, on a hunch, I looked at the calling template and changed it from this: <p tal:content="context/expensive_script">...</p> ...to this: <p tal:content="container/expensive_script">...</p> And presto, I now get only one entry, and every page on the site gives me a hit from that one entry. Is this really intended behavior? It's not obvious to me from the code why this is happening (or why it might be desirable). The cache manager stores and looks up items by their getPhysicalPath(), so I don't see why context vs. container is relevant. If I'd wanted the URL to be relevant, I would have put that in the REQUEST Variables configuration. This could be a performance hit for the unwary ... aside from all the unnecessary misses, we'd be using RAM on the order of N * M * S where N is number of cached items and M is number of pages in the site, and S is average size of return value. We only should be using N * S. -- Paul Winkler http://www.slinkp.com