Archiving. You've described archiving. Taking less-recently-used data off of main storage (RAM in this case) onto a slower, cheaper medium. Heck, the only reas

Archiving. You've described archiving. Taking less-recently-used data off of main storage (RAM in this case) onto a slower, cheaper medium. Heck, the only reason we have hard disks and memory is that it's not economically feasible to have billions of CPU registers, and that there's a further trade-off between volatility and speed. This is literally an older technique than the computer. Files are kept in the main office until they're not being used and then moved to the basement for long-term storage.