Path: utzoo!utgpu!attcan!uunet!lll-winken!lll-lcc!ncis.llnl.gov!helios.ee.lbl.gov!nosc!ucsd!rutgers!rochester!pt.cs.cmu.edu!andrew.cmu.edu!wb1j+ From: wb1j+@andrew.cmu.edu (William M. Bumgarner) Newsgroups: comp.sys.mac Subject: Re: Virtual memory init Message-ID: Date: 20 Jan 89 22:44:38 GMT Organization: Carnegie Mellon, Pittsburgh, PA Lines: 33 The ability to be able to run more applications under MultiFinder is an excellent and needed ability of the Virtual Mem Init, but it isn't the main purpose. By using a virtual memory manager, it allows an application to run as if it had a lot more memory available then the physical RAM in the machine. This function causes the need for the PMMU. The possibility of swapping in/out partitions under MultiFinder would work well for applications that DON'T support backgrounding. With the whole partition out of RAM and on disk, every time the application does something in the background, the partition would have to be swapped in to memory (meaning a write of the current partition and a read of the one executing if everything won't fit in memory). The performance wouldn't be real stupendous... For something like HyperCard, it would be wonderful-- I would like to keep HyperCard open all the time (I have set up Dazzl's Organizer+ to replace all file/launching management, plus I keep all my assignments/due dates in the stacks with links to the associated word-processing stacks-- avoids the SFGetFile folder mazes or a cluttered desktop), but sometimes it is simply impossible because of memory constraints. Considering that Hypercard doesn't support backgrounding (it kind of does, but not reall), and I often don't go to the Hypercard partition for 3+ hours, it would be incredibly useful to free up that layer! How about another bit in multifinder that allows a move-partition-to-disk on suspend/resume events? Multifinder basically does what it does with BlockMoves, so why not drop the mem out on a hard drive? Apple? Is it possible or not? b.bum wb1j+@andrew.cmu.edu