> by evicting more than one key when at capacity (say, evict n% of total keys) Ristretto does that already. It evicts as many keys as needed to stay within the

> by evicting more than one key when at capacity (say, evict n% of total keys) Ristretto does that already. It evicts as many keys as needed to stay within the MaxCost. This is done outside the critical path by background goroutines. However, you also don't want to evict too many keys, because that would affect the hit ratios.