They've tried things like choosing something at random or applying what's called the "first-in, first-out principle," which means removing the item which has been in the memory for the longest.
Próbálkoztak a véletlenszerű választással, vagy az úgynevezett  "first-in, first-out" elvvel, ami azt jelenti: azt törli a gép, ami legkorábban került a memóriájába.