This assertion highlights the efficiency of using append-only memory maps for data storage. In such a system, the main operation involving the disk is the periodic flushing of data to free up RAM. This process ensures that if there is enough RAM available, the disk usage is minimized, thereby reducing the impact of disk speed on overall performance. This insight shifts the focus towards optimizing RAM allocation and management as a way to enhance IBD efficiency rather than being overly concerned with disk speed limitations.