Also, as has been pointed out by another commenter, 8GB of swap for a system with 8GB of physical memory is overkill.
Genuinely curious where this idea has come from. Is it something being taught currently?
You can ask your favourite search engine or language fabricator about the differences between RAM and disk storage, they will all tell you the same thing. Frankly, it's kind of astonishing that this needs to be explained on a site like HN.
It does note main differences (speed, latency, permanence). How does that limit what data disk can be used for?
What would one use optane DIMMs for?
Also, if my program requires huge working set to process the data, why would I spend the effort and implement my own paging to templrary working files, instead of allocating ridiculous amount of memory and letting OS manage it for me? What is the benefit?
Note that simply buying more RAM than what you expect to use is not going to help. Going back to my post from earlier, I had a laptop with 8GB of RAM at a time where I would usually only need about 2-4GB of RAM for even relatively heavy usage. However, every once in a while, I would run something that would spike memory usage and make the system unresponsive. While I have much more than 8GB nowadays, I'm not convinced that it's enough to have completely outrun the risk of this sort of behaviour re-occuring.