Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sdd.hp.com!zaphod.mps.ohio-state.edu!cis.ohio-state.edu!ucbvax!bloom-beacon!bloom-picayune.mit.edu!athena.mit.edu!pshuang From: pshuang@athena.mit.edu (Ping-Shun Huang) Newsgroups: comp.sys.ibm.pc.misc Subject: Re: DOS 5 and memory management Message-ID: Date: 19 Jun 91 01:15:55 GMT References: Sender: news@athena.mit.edu (News system) Organization: Massachusetts Institute of Technology Lines: 16 In-Reply-To: cb@tamarack12.timbuk's message of 17 Jun 91 21:11:53 GMT In article cb@tamarack12.timbuk (Chris Brewster) writes: > Since the new DOS has paging and task switching, I'm unclear on what is > still needed from a memory manager. Is QEMM or MAX still useful? DOS 5.0 does provide task switching, but it does not provide paging; swapping, yes, but not paging. Remember, paging is done on a fixed-sized small memory block basis (swapping is done on arbitrary segment sizes), and for i386's there is hardware support in the chip for paging 4Kb blocks, if an OS wish to implement it for virtual memory purposes. Neither DOS nor QEMM nor MAX will provide this kind of utility; however, OS/2 and Windows (?) do. -- Singing off, UNIX:/etc/ping instantiated (Ping Huang)