osborn@ux1.lbl.gov (James R Osborn) (06/06/91)
I was using the Memory Manager INIT with my IIci prior to installing System 7. The documentation that came with the init did a nice job (I thought) of explaining what was wrong with the memory manager on various Macs including the IIci. The problem made it very inefficient under certain circumstances when allocating memory (Ptrs and Handles). I'd like to know from someone in the know if this really was or is a problem with the ROMs for certain machines? Has System 7 patched or otherwise corrected the memory manager so that this init is no longer necessary? If not, then is this init approved of by anyone at Apple for correcting the problem? -- James .------------------------------.--------------------------------------. | James R. Osborn | It just goes to show you it's always | | Lawrence Berkeley Laboratory | something. Either it's baffling | | osborn@ux1.lbl.gov | tech notes or your mac is smoking. | | (415) 548-8464 | It's always something... | '------------------------------'--------------------------------------'
gad@eclipse.its.rpi.edu (Garance A. Drosehn) (06/06/91)
In article <13953@dog.ee.lbl.gov> osborn@ux1.lbl.gov (James R Osborn) writes: > I'd like to know from someone in the know if this really was or is a > problem with the ROMs for certain machines? Has System 7 patched or > otherwise corrected the memory manager so that this init is no longer > necessary? If not, then is this init approved of by anyone at Apple > for correcting the problem? It really was a problem on some machines (my Mac IIci for instance), but the problem is only noticable with a very small number of programs. Like, two or three different programs. If you did not notice a dramatic speed improvement in anything you did after installing the init, then chances are the problem did not really effect you at all. These problems are fixed with system 7. Do not even think of using the init if you are running system 7. System 7 fixes the same things, and includes other changes which you'll only lose if you install the init. You'll definitely make your life worse if you run this init with system 7. If you're still running system 6 then you can think about it, but it isn't really a good idea. It's quite possible that running the init with system 6 will cause you more problems then it will solve. In my case it was worth running the init, but for the vast majority of Mac users it is not. - - - - - - - - Garance Alistair Drosehn = gad@rpi.edu or gad@eclipse.its.rpi.edu ITS Systems Programmer (handles NeXT-type mail) Rensselaer Polytechnic Institute; Troy NY USA
mjohnson@Apple.COM (Mark B. Johnson) (06/06/91)
In article <13953@dog.ee.lbl.gov> osborn@ux1.lbl.gov (James R Osborn) writes: > >I was using the Memory Manager INIT with my IIci prior to installing >System 7. The documentation that came with the init did a nice job >(I thought) of explaining what was wrong with the memory manager on >various Macs including the IIci. The problem made it very inefficient >under certain circumstances when allocating memory (Ptrs and Handles). > >I'd like to know from someone in the know if this really was or is a >problem with the ROMs for certain machines? Has System 7 patched or >otherwise corrected the memory manager so that this init is no longer >necessary? If not, then is this init approved of by anyone at Apple >for correcting the problem? > Since this questions keeps coming back and I know Keith is tired of answering it, following is the official Apple position on the MMInit which many of you are still using (and should not be). What follows is the official position, but the basic word is do not use it under either System 6.0.x or System 7.0. __________ Under System 6.0.x, Apple had identified a minor problem with the Memory Manager in the Macintosh IIfx, IIci, IIsi and LC. This problem resulted in a performance degradation in an extremely small number of applications and did not cause system crashes. We believe this was an insignificant problem that affected few applications and very few customers. The problem was not new and was not caused by the introduction of System Software 6.0.5 or 6.0.7. Based on developer feedback, customer feedback, and extensive in-house testing, Apple has identified very few affected applications. Because the problem only affects an extremely small number of developers, Apple is working with those developers to fix their applications. The best solution, however, is to upgrade to System 7.0, as it includes an enhancement to the Memory Manager to address this issue. During extensive testing and research, Apple investigated a variety of solutions to enhance the Memory Manager performance. One area researched was a software solution called the Memory Manager INIT (a software "patch") or MMInit as it is most often called. Through testing we discovered that this patch did not enhance Memory Manager performance and introduced risks such as decreased performance in some mainstream applications. An unofficial version of the Memory Manager INIT has surfaced. This INIT should not be used, because it has been modified from Apple's experimental version and could cause data corruption, data loss, and crashes. Apple strongly urges that you discard the INIT if you have obtained a copy, and not use it. If any version of this INIT is used under System 7.0, it defeats the enhanced Memory Manager and reintroduces the bugs which where present in the System 6.0.x Memory Manager. You may still wonder if you have been affected by this and how to avoid it under 6.0.x. The problem is most severe when allocating pointers in a heap with a rather large number of handles (on the order of tens of thousands). It's helpful to allocate enough master pointers (via MoreMasters) during initialization. If the Memory Manager has to call MoreMasters later on, not only could it fragment memory, but it could take an exceedingly long time. It's also helpful not to allocate thousands of handles. Besides requiring lots of master pointers, it takes the Memory Manager a long time to crunch through them during heap compaction. Chances are you're not being plagued by this rare "bug." Before you go crazy wondering if the "bug" exists in your computer, read and check the following list of factors affecting CPU performance: % Monitor size, bit depth, color or black and white % On-board video versus video card % Hard disk size, fragmentation, interleaving (which CPU the hard disk was initialized on, and which CPU is now using it) % AppleTalk active % Servers mounted % Electronic mail installed % Public Folders (shared folders) % INITs installed % Fragmented heap (other applications could fragment/corrupt the system heap) % Amount (and speed) of RAM % Mixing speeds of RAM (causes random crashes) % Finder vs. MultiFinder % Disk cache % Cache cards installed % Floppy disk access % Peripherals connected (such as CD-ROM and tape drives) % Background printing If you're indeed experiencing a performance proglem, make sure that the above conditions are not contributing to it. __________ -- Mark B. Johnson AppleLink: mjohnson Developer Technical Support domain: mjohnson@Apple.com Apple Computer, Inc. UUCP: {amdahl,decwrl,sun,unisoft}!apple!mjohnson "You gave your life to become the person you are right now. Was it worth it?" - Richard Bach, _One_
keith@Apple.COM (Keith Rollin) (06/07/91)
In article <13953@dog.ee.lbl.gov> osborn@ux1.lbl.gov (James R Osborn) writes: > >I was using the Memory Manager INIT with my IIci prior to installing >System 7. The documentation that came with the init did a nice job >(I thought) of explaining what was wrong with the memory manager on >various Macs including the IIci. The problem made it very inefficient >under certain circumstances when allocating memory (Ptrs and Handles). > >I'd like to know from someone in the know if this really was or is a >problem with the ROMs for certain machines? Has System 7 patched or >otherwise corrected the memory manager so that this init is no longer >necessary? If not, then is this init approved of by anyone at Apple >for correcting the problem? Excutive summary: - There really was a problem in the LC, IIsi, IIci, and IIfx. - System 7.0 fixes the problem. - The problem affects only 2 or 3 programs. If you aren't running them, then you will not see a problem. None of these programs are in the "Top 100 Macintosh Programs of All Time". - DON'T run the init under 7.0, as it will re-introduce bugs that 7.0 fixes. - The INIT was written as a test to see if the specific bug in question could be fixed. In its current form, it was never intended to leave Apple, and was never tested. Although it was written by someone at Apple (me), it is in no way approved. -- ------------------------------------------------------------------------------ Keith Rollin --- Apple Computer, Inc. INTERNET: keith@apple.com UUCP: {decwrl, hoptoad, nsc, sun, amdahl}!apple!keith "But where the senses fail us, reason must step in." - Galileo
osborn@ux1.lbl.gov (James R Osborn) (06/08/91)
In article <53702@apple.Apple.COM> mjohnson@Apple.COM (Mark B. Johnson) writes: >In article <13953@dog.ee.lbl.gov> osborn@ux1.lbl.gov (James R Osborn) writes: >> >>I was using the Memory Manager INIT with my IIci prior to installing >>System 7. The documentation that came with the init did a nice job >>(I thought) of explaining what was wrong with the memory manager on >>various Macs including the IIci. The problem made it very inefficient >>under certain circumstances when allocating memory (Ptrs and Handles). >> >>I'd like to know from someone in the know if this really was or is a >>problem with the ROMs for certain machines? Has System 7 patched or >>otherwise corrected the memory manager so that this init is no longer >>necessary? If not, then is this init approved of by anyone at Apple >>for correcting the problem? >> > > [...] > >If you're indeed experiencing a performance proglem, make sure that the above Mark, thanks for the info., but what's a ... ^^^^^^ ? (I'm not sure if I'm experiencing any of those 8^) >conditions are not contributing to it. >__________ > >-- >Mark B. Johnson AppleLink: mjohnson >Developer Technical Support domain: mjohnson@Apple.com >Apple Computer, Inc. UUCP: {amdahl,decwrl,sun,unisoft}!apple!mjohnson > >"You gave your life to become the person you are right now. Was it worth it?" > - Richard Bach, _One_ Is it not fair to tell us the name of those "very-few-and-not-in-the-Top-100- Macintosh-Programs-of-All-Time" programs that did have problems? You don't have to answer that if you don't want to, I'm certain I'm not using one the programs in question - just curious. -- James .------------------------------.--------------------------------------. | James R. Osborn | It just goes to show you it's always | | Lawrence Berkeley Laboratory | something. Either it's baffling | | osborn@ux1.lbl.gov | tech notes or your mac is smoking. | | (415) 548-8464 | It's always something... | '------------------------------'--------------------------------------'