hugo@maxlin.dartmouth.edu (Peter Su) (06/23/88)
Hi folks... Well, with all the moaning about the memory requirements of LSC and other things, I thought I would try to say something that's been on my mind...se, I'm not really mad at THINK, or the Fullwrite people, because it's not really their fault that their software needs so much memory to run with Multifinder, in my mind, the problem is Apple's non-OS. Let me explain: See, on some computers, when you run multiple tasks, the OS keeps can (gasp!) swap out code and data that are not currently being referenced, and (gee!) you don't have to allocate like and entire MB of memory for (say) Excel, when in fact you may actually use only half of it at any given time, but there is some extreme case where it will need it all. See, the OS manages the DYNAMIC memory requirements of the programs that are running, and so the developer doesn't have to worry so much. This business with paritions is just such an incredibly dirty hack that it's almost sickening. So when you are moaning about needing 2MB for LSC, reember that Apple is also to blame, because their OS, well, isn't one. Disclaimer: Now, you all are thining, geez, what a UNIX/MSDOS/IBM bigot. Not so! I think the mac is great, but I can't stand the thought of programming the thing,because it is just too painful. Cheers, Pete
adail@pnet06.cts.com (Alan Dail) (06/23/88)
One thing I think you are overlooking in complaining about the fact that
the Mac OS doesn't support virtural memory yet is that any system I know
of that supports virtural memory seem to require 2-4 MB just for the OS.
Alan Dail
UUCP: {crash uunet}!pnet06!adail
ARPA: crash!pnet06!adail@nosc.mil
INET: adail@pnet06.cts.comblknowle@uokmax.UUCP (Bradford L Knowles) (06/24/88)
In article <8980@dartvax.Dartmouth.EDU> hugo@maxlin (Peter Su) writes: >[... stuff deleted ... ] the problem is Apple's >non-OS. > >Let me explain: See, on some computers, when you run multiple tasks, >the OS keeps can (gasp!) swap out code and data that are not currently >being referenced, and (gee!) you don't have to allocate like and >entire MB of memory for (say) Excel, when in fact you may actually use >only half of it at any given time, but there is some extreme case where >it will need it all. See, the OS manages the DYNAMIC memory >requirements of the programs that are running, and so the developer >doesn't have to worry so much. > >Cheers, >Pete Pete, the system already does this. If a resource is listed as "purgeable" then the system will "unload" it if more memory is required. Admittedly MultiFinder doesn't dynamically reallocate memory for programs, but this is one of its first incarnations -- when Apple does add this feature, then you can be guaranteed that people will bitch because the system takes up too much meomory, a price we will all have to pay if we want mainframe and minicomputer performance out of a microcomputer. So waddya want? The universe on a dime budget? Not even Apple can deliver *THAT*! -Brad Knowles UUCP: ...!ihnp4!occrsh!uokmax!blknowle ARPA: blknowle@uokmax.ecn.uoknor.edu SNAIL: 1013 Mobile Circle Norman, OK 73071-2522 -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Philosophy of Boris Yeltsin: "If one wants to be unemployed, one will criticize ones' boss. If one wants to be sent to Siberia, one will criticize the wife of ones' boss." -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Disclaimer: (The above opinions are my own. They have nothing to do with the Univeristy of Oklahoma nor intelligance of any sort. :-)
jimc@iscuva.ISCS.COM (Jim Cathey) (06/25/88)
In article <242@hodge.UUCP> adail@pnet06.cts.com (Alan Dail) writes: >One thing I think you are overlooking in complaining about the fact that >the Mac OS doesn't support virtural memory yet is that any system I know >of that supports virtural memory seem to require 2-4 MB just for the OS. The Kernel (both code and data) of our Unix variant occupies about 250K. We run in 1MB of physical RAM, and can in fact run (though quite a bit slower due to increased swapping) in 512K of RAM. The virtual space is 2MB right now because of a limit in the MMU. It _is_ possible to run virtual on smaller machines. The biggest problem seems to be programmers who then don't realize that these _are_ smaller machines! Of course, I am not proposing that VM could just drop into the Mac OS for a paltry memory fee. There are a lot of technical issues to solve (unless you want VM with no intertask protection -- that would be quite a bit easier). +----------------+ ! II CCCCCC ! Jim Cathey ! II SSSSCC ! ISC Systems Corp. ! II CC ! TAF-C8; Spokane, WA 99220 ! IISSSS CC ! UUCP: uunet!iscuva!jimc ! II CCCCCC ! (509) 927-5757 +----------------+ "With excitement like this, who is needing enemas?"
jmunkki@santra.HUT.FI (Juri Munkki) (07/01/88)
In article <1658@iscuva.ISCS.COM> jimc@iscuva.ISCS.COM (Jim Cathey) writes: >Of course, I am not proposing that VM could just drop into the Mac OS for a >paltry memory fee. There are a lot of technical issues to solve (unless you >want VM with no intertask protection -- that would be quite a bit easier). Of course that is what I want and what I think most people would like. Since the Mac currently has absolutely no protection between applications, there would be no harm from a virtual system without protection. I estimate that it would take a good Mac programmer about a week to write a beta version and about two months to make it a product. Tell me why it can't be done. It wouldn't hurt apple's image to be able to advertise that the Mac has virtual memory. I already suggested this earlier and got no replies. Are MMUs harder to find than 1M DRAMs? Juri Munkki jmunkki@santra.hut.fi jmunkki@fingate.bitnet P.S. Give me a MMU and the manuals and I'll write a swapper.
landman%hanami@Sun.COM (Howard A. Landman) (07/07/88)
In article <242@hodge.UUCP> adail@pnet06.cts.com (Alan Dail) writes: >One thing I think you are overlooking in complaining about the fact that >the Mac OS doesn't support virtural memory yet is that any system I know >of that supports virtural memory seem to require 2-4 MB just for the OS. Can't you buy a uVAX II running Ultrix with only 1 MB? More is recommended, but doesn't 1 MB work? Certainly, Sun 2s were available in 2 MB configurations, and could run reasonably large programs. Here are the memory configurations that I have been able to discover for the Sun family (disclaimer: I haven't been here long enough to know what I'm talking about!): Model Min-Max Mem (MB) 4/110 8-32 386i/250 8-16 386i/150 4-16 3/200 8-128 3/180,/160 4-16 3/140,/110 4-12 3/60 4-24 3/50 4 2/160,/130,/50 2-? Roughly, the minimum memory configuration seems to double every generation. Anyway, a 2 MB system puts the lie to "require 2-4 MB just for the OS". Howard A. Landman landman@hanami.sun.com UUCP: sun!hanami!landman
dcw@ecsvax.uncecs.edu (Douglas C. Wilson) (07/08/88)
In article <59085@sun.uucp> landman@sun.UUCP (Howard A. Landman) writes: >Can't you buy a uVAX II running Ultrix with only 1 MB? More is recommended, >but doesn't 1 MB work? > Howard A. Landman > landman@hanami.sun.com > UUCP: sun!hanami!landman The current version of ULTRIX-32 requires a minimum of 4 meg just to boot. Any real work takes more. -- Doug Wilson Internet: dcw@rwlvax.chem.unc.edu Dept. of Chemistry BITNET : WILSON@UNCCHEM,WILSON@UNCVAX Univ. of North Carolina UUCP : mcnc!ecsvax!dcw Chapel Hill, NC 27599 Phone : 919-962-1582, 1583
phssra@emory.uucp (Scott R. Anderson) (07/12/88)
In article <59085@sun.uucp> landman@sun.UUCP (Howard A. Landman) writes: >In article <242@hodge.UUCP> adail@pnet06.cts.com (Alan Dail) writes: >>One thing I think you are overlooking in complaining about the fact that >>the Mac OS doesn't support virtural memory yet is that any system I know >>of that supports virtural memory seem to require 2-4 MB just for the OS. > >Certainly, Sun 2s were available in 2 MB configurations, and could run >reasonably large programs. The Sun-1s came with 1MB standard. Running SunWindows was painful, but otherwise it worked fine (if your programs weren't monsters). As I recall the kernel could be as small as 400K. This might still be true, but it's been a while since I adminstered one, so I don't know for sure. The large amounts of memory currently seen on Suns are the result of lower memory prices and the realization that SunView runs much, much better if you never have to swap :-). * Scott Robert Anderson * ** gatech!emoryu1!phssra * * * ** phssra@emoryu1.{bitnet,csnet} * * * * * ** * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *