philip@pescadero.Stanford.EDU (Philip Machanick) (05/25/91)
Something I've been wondering about for some time is why we have to put up with increasingly slow restart time. With VM, I wonder if it would be possible to save a snapshot of system state and restart from that. I realize that this wouldn't be totally free. Dirty pages would have to be written to disk at shutdown time, and paging in at reboot would not be instantaneous - but surely quicker than waiting for a dozen extensions to relaunch. There are other potential problems, like what to do about open files, or if the system is restarted from a different disk. Still, it seems an idea worth following up. Another thought - something for debugging - if a program crashes, instead of killing it and restarting, save VM, and reboot to a debugger (which should be running in a stable state, but with the complete state at the time of crash preserved to examine). Both these ideas are easier to implement with Apple's model of saving all of VM, not just the portion that's not in real memory. -- Philip Machanick philip@pescadero.stanford.edu