I don't think the keyset will be in ram: "Redis will never use more RAM, even if we have 2 MB of max memory and 1 billion of keys. This works since now we don't need to take keys in memory."
I haven't looked at the current code to see if there is a way to favor keeping the keys in memory, but it would seem that wildcard searches here can/will be disk-bound.
tokyo supports a b-tree index on the keys written to disk which would optimize blah* queries but not [wildcard]foo[wildcard], and then writes become log(N)
I haven't looked at the current code to see if there is a way to favor keeping the keys in memory, but it would seem that wildcard searches here can/will be disk-bound.