You
can use cache.ram, but each process will have its own cache. That shouldn't affect expiration at all, though, as with cache.ram, the expiration is determined at
retrieval time, not at the time of the initial write, and cache keys are not automatically purged after some period. Of course, in one request, you might put something in the cache of one process, and the very next request might hit a different process and therefore not have access to that cached item (so it will then be written to the cache of the second process).
Anthony