Double paging definition

This is not a programming question but more of an operating system question

Right now I'm trying to learn what exactly Double paging means.

I see two different terms, double paging on disk and double paging in memory.

Apparently this problem arises when we introduce a buffer cache to store disk blocks when doing File I/O

But I'm not really sure what exactly this term means. If anybody could specify it would be very helpful.

It's a problem that occurs when you have a system that is running in a very high-memory utilization state where much of the physical memory is owned by a critical OS resource (like the kernel) and therefore, can't be swapped out by the usual means. It's a fairly common problem to have to dodge in virtualizing OS instances. There's a brief blurb on it here:

http://www.usenix.org/events/osdi02/tech/waldspurger/waldspurger_html/node5.html

What is the specific context of your question?