I am looking for a data-structure that stores 32bytes strings and allows fast lookups with preferred O(1) or O(log N) lookup complexity (the goal is only to determine if the key exists). Removal and insertion complexity is not critical, since those operations will be infrequent.
Not that it is relevant to the question, but i am working in Go. I could use a hashmap backed by a mutex, but contention would be a problem, and I prefer to avoid sharding if there is a better solution.
Thanks