I don't quite understand Dries remark "I'm fairly convinced that memory-based caching ... is the way forward rather than file-based caching." That remark seems to presuppose knowing every site's and host's situation (impossible) or to say that file-based caching will never provide enough performance benefit over what we have now.
<br><br>I think the real way forward is object-based caching hooks in core and a pluggable cache interface. Ideally, one would have tiered caching, so that more than one cache mechanism could be plugged in, and various types of caching (object, page, menu, query, etc.) could be assigned to one of the available mechanisms. However, that ideal would be many steps down the road, if ever, due to the complexity involved.
<br><br>Instead, we should at least allow site owners to chose amongst memory, file and database caching at a minimum.<br><br>As for object-based caching, start with nodes. Eventually, add other common objects, e.g. users, and provide an API(?) to make it easy for contrib modules which create new objects to cache their objects as well.
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