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Long live the Thing King!

And, as it did in 1972, virtual memory gives you the effect of about twice as much real memory. Back then, a megabyte of memory cost about a million dollars. Today, a gigabyte of memory costs about five dollars. Why are we still bothering with paging?

Process isolation is easier with virtual memory. Gpus went through this transition recently or in the case of Linux very recently.
Having an MMU is fine. Paging out to disk isn't worth it. The price of paging is erratic response times.

Note that few mobile devices page. It's a legacy of the desktop/server era.

Virtual memory is primarily a convenient abstraction to give the illusion of having infinite memory.
This inspired a project I worked on with some collaborators a while back. DOI: http://dx.doi.org/10.5281/zenodo.10773 and code: https://pypi.python.org/pypi/thingking

We used it to enable analyzing trillion particle dark matter simulations a halo at a time, as though they were local. It was fun. We made it part of the way into implementing an fopencookie version, but ended up moving on to other projects.