Re: Ahh, Amiga
Pre-emptive multitasking can work just fine without memory protection. Provided every other application and process doesn't vomit over your memory. Sadly, this was never true in my year-long experience of owning an Amiga. I traded it back in against an Atari 520STE: not as clever, no multitasking, and the games were nowhere near as good, but at least it didn't crash unless I made it crash (ah, the joys of 68k assembly!)
This isn't really Amiga's fault though - there was simply no hardware to deal with the inevitable instability that comes from multitasking. I seem to remember that the 68000's companion MMU was a bit of an afterthought, so nobody used it, and in any case the 68000 itself had no way to properly recover from a bus error, so even with protection, a process reading from an out-of-address-space location could still hose your system. (68010 allowed the system to restart after memory fails)
Ah, the old days...
Biting the hand that feeds IT
