Xcode alone can fill the RAM on a 16GB system. Yeah, okay, half of that is "Cached Files" (not app memory) so the effect is subtle. Incremental builds are 5% slower compared to a 32GB system but clean builds are about the same. (Blue is 16GB, green is 32GB, lower is faster.) Everything takes different amounts of RAM based on the total RAM of the system. My 16GB system running Xcode shows 8GB "Memory Used" in Activity Monitor but the 32GB system shows 12GB. (The Xcode process shows just 586MB used, the rest spread around 822 other processes.)

I've been writing the App Architecture book for so long that now it's done, I'm finding it difficult to just switch off. So here's some behind-the-scenes fun facts from writing App Architecture... Fun fact #1: The first week on the book, we each independently wrote an MVC app. The MVC app used in the book is derived from the model layer Chris wrote, the folder navigation I wrote and the player and recorder Florian wrote in this first week.