> It's not the performance cost, it's rewriting all the pointers. Which you don't need to do > Without address translation, copying the existing mappings to a new > range requires finding and adjusting every pointer to the old data, No it doesn't. See Minix. When you fork() rather than vfork you stick a copy of any non-relocatable elements (typically DATA copy + BSS + stack with a sane CPU and compiler) into a buffer and you swap them over with the real copy when you task switch to the one in the wrong place. If you start the child first you usually only take one copy. I've always been amused that Linux NOMMU hasn't managed to grow a feature that people successfully implemented on 68000 long long ago, and I believe some other processors back to v6/v7 days. Alan -- To unsubscribe from this list: send the line "unsubscribe linux-embedded" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
