No, It's Not Always Quicker To Do Things In Memory
itwbennett writes: It's a commonly held belief among software developers that avoiding disk access in favor of doing as much work as possible in-memory will results in shorter runtimes. To test this assumption, researchers from the University of Calgary and the University of British Columbia compared the efficiency of alternative ways to create a 1MB string and write it to disk. The results consistently found that doing most of the work in-memory to minimize disk access was significantly slower than just writing out to disk repeatedly (PDF).
They used Java and Python. Draw your own conclusions from that. ;)
Quo usque tandem abutere, Nimbus, patientia nostra?