We have a use case when we have an endless stream of MinHashes which we continuously compare against MinHashes we have seen before. If we haven't seen it, we add it to the index. We are using Redis as our backend and from time to time we need to switch instances because they reach 32Gb in size and cannot grow more (today this takes about 4 months for us, but we get more data day by day). For our use case it would be ideal if we could specify a last_seen key for a MinHash to implement an eviction policy, but for all I understand this is not possible? Or is it?