And All of a Sudden: Main Memory Is Less Expensive Than Disk

Even today, the wisdom for storage still is that storing data in main memory is more expensive than storing on disks. While this is true for the price per byte, the picture looks different for price per bandwidth. However, for data driven applications with high throughput demands, I/O bandwidth can easily become the major bottleneck. Comparing costs for different storage types for a given bandwidth requirement shows that the old wisdom of inexpensive disks and expensive main memory is no longer valid in every case. The higher the bandwidth requirements become, the more cost efficient main memory is. And all of sudden: main memory is less expensive than disk.