Since the (real) Mac OS and all Mac OS applications run in the same (supervisor) memory space, it doesn't seem like there would be any need for the MMU except for VM... That said, the lack of an MMU would prevent the running any Unix OS as they all (to my knowledge) require it.
Derek On Nov 25, 2009, at 10:27 AM, Scott Holder wrote: > > Jeff Walther wrote: >> >> I'm surprised it would run at all. I had always assumed that with >> the >> MMU stripped out the Macintosh would be missing an essential >> component. I'm surprised the operating system can handle the lack of >> an MMU. It would be interesting to see what happens if Britt >> tries to >> turn Virtual Memory on. >> >> Jeff Walther > > For a long time, the 68k Mac emulators like Basilisk II didn't emulate > the MMU. I don't know if they still don't, I haven't messed with it in > awhile (Plenty of real Macs to mess with now ;) ). But, they pretty > much worked fine. > > The net result was the Virtual Memory was completely non- > functional; if > you turned it on, it'd just show off the next time you booted. Also, > alternative OSes such as Linux and BSDs that depend on MMUs for core > functions wouldn't work. Apparently, the Mac OS itself (at least > through > the 8.1 that 68ks support) doesn't need or care about the MMU aside > from > VM. I don't recall now whether some of the specialized apps like > Photoshop that did its own VM and caching worked, but I think they > did. > > Scott --~--~---------~--~----~------------~-------~--~----~ ----- You received this message because you are a member of the Vintage Macs group. The list FAQ is at http://lowendmac.com/lists/vintagemacs.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to [email protected] To leave this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/vintage-macs Support for older Macs: http://lowendmac.com/services/ -~----------~----~----~----~------~----~------~--~---
