docs: public void setCacheSize(int cacheSize) {
      this.cacheSize = cacheSize;
  
      long toDelete = map.size() - this.cacheSize;
      if(toDelete <= 0) {
        return;
      }
  
      List<Integer> keys = new ArrayList<>(map.keySet());
      Collections.reverse(keys);
  
      for(Integer id : keys) {
        P page = map.remove(id);
        file.writePage(page);
      }
    }