Can’t remember where I read it on here, but some guy (well known?) made a dream last for 100 years, obviously not IRL. But there is a technique you can do to stop time in your dream. A good thread might be: [Slowing Down Time in Lucidity) though it’s not the one I’m looking for. I guess it has to do with the theory of relativity. 
It’s something I plan to do next time I’m lucid.