Comment 7 for bug 1578401

This is not a bug. Dogpile.cache can set an actual memcache expiration, however, we have simply been leaning on the LRU capabilities on memcache. For keystone this would need to be changed in oslo.cache not in Keystone.

I am marking this as opinion, it's not really a bug, it is how we have implemented the cache. We can revisit this if there is a desire as an RFE for oslo.cache.