I have not read about the architecture of the hardware, but on your toes can explain.
Memory is divided into pages.
Page dispatched on the subject of obsolescence.
If the memory page have not appealed, it becomes a candidate for eviction in the swap.
If the processes do not have enough RAM for a maneuver, page-candidates fly in the swap, accordingly, they are marked as superseded.
If some process need to get the data from the addresses, calculates which page the address belongs.
If the page is evicted, then taking steps to get her back in the RAM.