Mac OS 9.2.2 Memory Limit of 1.5 GB... Some Answers

[nanopico]

Two things as an update to the 2GB shenanigans.
1. I'm working on a program that can call the previously identified functions (the ones that grow the system heap, shrink the system heap, grow the process manager heap and shrink the process manager heap).  These functions are all part of the memory manager.  As these are private functions there will be no headers with definitions for them and the standard methods of linking from the compiler will complain about a lot of things.  So at the moment I'm working out a way to call these.  The intent of this first program is that you can run it and move the boundary between the two heaps to manually adjust the ram usage.  Not sure if it will work, but that's the goal.

2.  While digging through the headers for the memory manager there is an interesting constant defined.  maxBlockSize.   I haven't looked at what it's used for, but it is just shy of 2GB. But as it's a block size it would be greater than one byte.  So on the surface it makes me wonder if there is someway to allocate an objet in code that is 2+ GB in size.  That would be interesting for sure.

[Texas_RangerAT]

It's merely an educated guess but I strongly suspect there's a simple reason for the discrepancy between Apple's RAM limit and actual capacity: Apple took whatever modules were available at the time of the machine's development, did extensive testing with those modules and then set that as a limit - forever. If larger SIMMs, DIMMs or whatever were introduced later during the machine's life Apple simply ignored that.

Another thing occurred to me last night. It might be totally unrelated since it affected much older software and hardware but I'm 99% sure I've run into the weird situation of the Finder claiming to use up a whole lot of memory before! My memories of that are extremely fuzzy as it must have been more than 15 years ago but I THINK that was when I tried installing 6.0.3 on a Mac IIcx or maybe IIci with more than 16 MB of RAM. At that time I supposed it was due to 6.x only supporting 24-bit address space or something like that I'd read. Another possibility (though less likely) is that I encountered it on a IIcx (which doesn't have full 32-bit addressing) running 7.5.5 without a 32bit enabler extension installed. I still have both machines so I could do some experimenting but I'm not sure if it's any help since we're talking about 68k hardware and 6.x/7x here.

[geforceg4]

it helps to look at things in perspective
imho u are looking at mac os 9 and judging ram vs performance in a way that the world has conditioned people to look at it since the use of mac OS X + ram sizes exploding into higher capacities.. but mac os 9 is descended from older lowly roots where more ram doesnt neccessarily mean more performance.

lets look at some numbers?

http://www.everymac.com/actual-maximum-mac-ram/actual-maximum-power-mac-g3-ram-capacity.html

here we see the beige g3's max out at 768Mb
the B+W G3s max out at 1024Mb

examining this page:
http://www.everymac.com/actual-maximum-mac-ram/actual-maximum-power-mac-g4-ram-capacity.html

we see that most g4motherboards dont support more than 1.5gb of ram PHYSICALLY limited by the slots...

but lets remember we are talking about an os with history... if u look at the early 1990s..
what was the std/max ram of the flagship machines? mac os 9 is basically the same os as mac os 7 but extended into the future...

http://www.everymac.com/systems/by_year/macs-released-in-1991.html
http://www.everymac.com/systems/apple/mac_quadra/specs/mac_quadra_900.html
STD:4MB!!!!!! MAX:64MB!!!!

http://www.everymac.com/systems/by_year/macs-released-in-1993.html
http://www.everymac.com/systems/apple/mac_quadra/specs/mac_quadra_840av.html
STD: 8mb!!!!! MAX:768Mb

http://www.everymac.com/systems/by_year/macs-released-in-1995.html
http://www.everymac.com/systems/apple/powermac/specs/powermac_9500_132.html
STD:16Mb! MAX:768Mb

http://www.everymac.com/systems/by_year/macs-released-in-1997.html
http://www.everymac.com/systems/apple/powermac/specs/powermac_9600_350.html
STD:64Mb MAX:768Mb

http://www.everymac.com/systems/by_year/macs-released-in-1999.html
http://www.everymac.com/systems/apple/mac_server_g3/specs/macserver_g3_450_bl.html
STD: 256Mb!!!! MAX:1GB

http://www.everymac.com/systems/by_year/macs-released-in-2001.html
http://www.everymac.com/systems/apple/powermac_g4/specs/powermac_g4_867_qs.html
STD:128MB MAX:1.5GB RAM

http://www.everymac.com/systems/by_year/macs-released-in-2003.html
http://www.everymac.com/systems/apple/powermac_g4/specs/powermac_g4_1.25_mdd.htm
STD: 256MB MAX:2GB RAM

even in 2003!!! after the mac os9  funeral... the mdd still shipped with 256mb ram!!!!!! only!

is it possible to think the logic that more ram = more performance doesnt neccessarily apply?
can we wrap our heads around that???  even in 1999 (the year mac os 9 was released) the most powerful mac was shipping with 256mb! most of them even less than that!

having 2GB ram was something that didnt even come into play with PC's untill 2001 with the NT Based Windows XP.. before that windows98se could only even accept 512mb!!!! half a gig MAX! limited by the OS!! the classic mac os works great with 1gb of ram!! you need'nt worry about increasing ram to increase your productivity or performance.. you are better off worrying about what you are actually doing with software programs rather then worrying about a few extra MB of ram hardware.

i dont understand the fascination with the subject of enhancing mac os 9..
even if u got it to take 4GB OF RAM somehow.. IT WOULD NOT MAKE A DIFFERENCE. the RAM is not the limiting factor for performance.
we are talking about an os that is descended from other mac os that used to use very small amount of ram, to do amazing things. 1991 running mac os 7, with only 4MB RAM!!!!!!!! new in the box, with only 4MB RAM!!! think about it..

i keep hoping one day the users of this forum will realize theres more to talk about in how they use the software then to be obsessed + fascinated with getting 2gb of ram to work when theres not much benefit.
to me, im much more interested to talk about drop down menus + functionality within software.. file conversion.. creative processes.. tactics to use multiple software programs together to achieve a better work flow result.
etc etc.. so much software here but noone is talking about how to use it
instead focused + obsessed with RAM size.. sigh

[DieHard]

i dont understand the fascination with the subject of enhancing mac os 9..
even if u got it to take 4GB OF RAM somehow.. IT WOULD NOT MAKE A DIFFERENCE. the RAM is not the limiting factor for performance.
we are talking about an os that is descended from other mac os that used to use very small amount of ram, to do amazing things. 1991 running mac os 7, with only 4MB RAM!!!!!!!! new in the box, with only 4MB RAM!!! think about it..

In most practical applications this is 100% true and let's also remember that programmers of this era were a different breed that prided themselves in a small memory footprint and efficient code... now that being said, for the musician that uses OS9 there would definitely be a major plus to get the 2 GB Limit usable.

For those of us that want to mix in the box and use virtual instruments/plugins under OS 9, then RAM is definitely a factor.  I have personally RAM out of RAM using VST plugins and still had 45% CPU still ready to go.  So although the average OS9 software does not need so much RAM, our digital workstations crave it, so much so, that even that extra .5 GB would let us load many more reverbs/delays and compressors.  So this "fixation" on getting more RAM has real world applications for some

[MacOS Plus]

  Actually, we're all just doing it for MacTron!

[DieHard]

  Actually, we're all just doing it for MacTron!

Yes, I second that

[geforceg4]

  Actually, we're all just doing it for MacTron!

doing what exactly tho??
wishing on a star? for an alternate universe? where macos9 takes 16gb of ram?

every other os tho, the limitations that were there when the os was current, still apply, this is not linux.
its not open source.. the chances of you guys really modifying + changing functionality of the os is very unlikely.
getting mac os 9 to run on a fw800 is a bit different because its somethng that was purposely disabled
its not something that was an incompatibility that was never overcome by the real developers.. u think there wasnt any
really skilled programmers at apple? who would have loved to advanced their career by coming up with the idea that doubled or quadrupled available ram to the OS???

but a few guys scratchin at notepad on a forums site can do it when the real pros couldnt? i dunno guys...
alot of times the best work is done by accepting + Working within the limitations

is anyone getting "out of memory" errors?

[geforceg4]

i find it ironic that im on a forums site for a 15 year old operating system, TO ESCAPE the  "never ending upgrade" crap... usually found with modern os + daw apps.. only to find most of the main users of the forum are obsessed with hacking the os to get that next performance bump upgrade 

[nanopico]

So if we accomplish this then do we get elevated to the "real pros" category?

[geforceg4]

All this memory is used by the 21 instruments loaded in 3 instances of Kompakt ( a software sampler).
I'm waiting to test nanopico's first work about this.  If I can have 512 mb more I could add 7 or 8 instruments more

why limit yourself to only one Mac?
its 2016.. we can buy another MDD for pocket change
why not just load up another mac with another audio interface + midi interface... and load up another 21 instruments?
in another 1.5gb of ram?

in my experience its better off when u dont stress the gear to its limit. but rather have each piece only do its one specific job, which means they react instantly rather then choke under load..

why not use an actual real peice of gear to alleviate some of the need like using a Korg Triton?

hardware midi setups have no ram limitations !! only limited by midi channels + audio channels..

[GaryN]

i find it ironic that im on a forums site for a 15 year old operating system, TO ESCAPE the  "never ending upgrade" crap.. only to find most of the main users of the forum are obsessed with hacking the os to get that next performance bump upgrade 

No, you're losing perspective. You're on a forum site with every type of user from casual gamers to actual working, revenue-producing professionals using a 15-year-old operating system because it works, it's "removed" from the "never ending upgrade" crap by virtue of being "obsolete" and running lots of "abandon-ware" that mysteriously manages to deliver results indistinguishable from this week's latest and greatest "magic-in-the-box" wonder system and all of the supposedly accurate plugin emulations of 15 to 25-year-old hardware.

"Wow! Have you seen the Harmonizer plugin? The graphics are so cool!"

The main users are not obsessed with hacking the OS…they're busy using the OS.
A few of the main posters however, have more time on their hands.
My point>>>   POSTERS ≠ USERS

It's OK though, there is / are a certain amount of shortcomings that were left hanging by Apple because Steve came back and he'd pocketed a LOT of $$ for Nextstep et al so OSX was therefore where the wind was blowing - period. Ultimately a necessary and basically good thing - but it did leave some very loose ends that could stand to be tidied up.

So if the hacker types manage to squeeze a little more performance out of our good 'ol OS, I say more power to them!
They do have incredible energy… I mean, coding OS9 with one hand / side of the brain while simultaneously probing the other side for illicit RF with the other hand (AND actually finding some), I gotta admit, that's sure as hell out of my league!

When you're feeling tweaked  (for lack of a better term - believe me, I know exactly how you feel) about this, just take a look at the member roster. You'll see there's a huge "silent majority", many of whom drop in, find what they need and go back to work. There are undoubtedly even more "unregistereds" that have found resources in the open categories. Actually, most users don't post at all unless they need help with something or really have something to offer.

So relax. It's takes all kinds and ultimately it's all good.


…but if and when someone you've been totally convinced is absolutely certifiably unhinged suddenly drops a posting like:

"A way to create premptive multitasking and multiprocessor memory management in G4's under OS 9.2.2"

and it works…

[geforceg4]

alot of times the best work is done by accepting + Working within the limitations

is anyone getting "out of memory" errors?

i have expressed what i felt i needed to express my work here is done lol

[DieHard]

Like I mentioned, running a studio under OS9 in the box will definitely run out of RAM at one time or another. 

Yes, G4s are cheap, but having multiple noisy G4s with extra cables and monitors are NOT the answer for many users; it may look cool, but many musicians have very little space due to nagging wives and other family obligations and most of the time are crammed in a small corner of the den as the "DAW cave".

So, I really believe, any efforts of maximizing OS 9 to "squeeze" more out of it, are not in vain.

Besides, it's fun to do what the Pros would not do... you act like that had a choice, they were hired employees that signed non-disclosures and were specifically told what to code, and what not to code.  Even if it was changing only a relative small amount of code to raise the RAM ceiling, I doubt any programmer that was making good money would make that argument with management.  They did as they were told, not as they wanted to... so to imply that "the pros couldn't do it, so how can we", may not be an accurate assessment of the facts.

[MacTron]

  Actually, we're all just doing it for MacTron!

... well, I must to say - at least -

THANK YOU !

LOL

 

[DieHard]

i find it ironic that im on a forums site for a 15 year old operating system, TO ESCAPE the  "never ending upgrade"

You may see the member base grow even more.   And I would not be surprised it you see another site called "Snow Leopard Lives!" made by ..... me

I have setup about 8 DAWs under Yosemite and "el Crap-itain" and it is obvious that the newer OS X versions are so tailored to the Masses, that even the simplest of DAW functions are not very difficult to attain.  Driver issues, lock-ups/instability, poor timing and syncing of MIDI and Audio and taken a pretty big set backwards over the last 2 years.

The best combo I setup in the last 4 months was Mac Pro "Quad Core" 3.7 trash can, Yosemite, and Logic Pro X, and Apogee Symphony I/O 2x6 Audio Interface for a small project studio.  Excellent quality and the guy only had to shell out about $8000.

So, if you buy everything just right, you can get the stability we took for granted a few years ago

[nanopico]

Here's some good news.
I've written a set of tools for doing some of the work ELN and I have been working on.
Not all of the tools I'm working on are complete, but they are far enough along that I can start using them to find out internals of the System file.

So there are a bunch of function in the PrivateInterfaceLib and MemoryMgr libraries related to handling the System heap and Process Manager heap and the border between them.  I have now been able to make some calls to a few of these functions.  As of the moment, with out knowing the parameters, they all do nothing.  I also don't know the order to call them in yet. 
Now I just have to finish my tools so I can determine the parameters and calling order. 

Hooray Progress!

[nanopico]

I had to share this.  It's too amusing.
So in trying to figure out the right combination of calls and parameters I managed to lock up sheepshaver, but not before getting this screen shot.
Apparently I'm able to at least totally mess up the system and process manager zone boundaries.

Now if you have issues with the 512 MB lost when 2 GB is installed, then be warned.

I'm not even sure how the math works out to get these numbers, but the system taking up 3.65 GB when only 512 MB is installed, is totally crazy!

[DieHard]

Wow.. what a RAM pig... I never realized that Mac OS 9 used so much RAM...lol

[nanopico]

Wow.. what a RAM pig... I never realized that Mac OS 9 used so much RAM...lol

And it can also create RAM out of thin air.


Okay so more updates now that I am at home.

As I assumed earlier when you view About This Mac and see the 550ish allocated to Mac OS and pretty much 1.5 GB for everything else that this was because it took the total amount of RAM and subtract size of the process manager to determine the size to show as Mac OS.    Well my hand little tool confirmed this.  So as of right now I'm pretty confident in this view.
I was able to see that About This Mac showed 560 MB allocated to Mac OS, but the Heap size was only 48 MB (560 - 512) and 8 KB was free in the heap.  So basically everything between the system heap and the process manager heap is in limbo. 
Now to trick the System into giving me a handle to the process manager zone so I can grow that beyond the 1.5 GB limit.

[nanopico]

I'm going to back track a bit. Moving the point that the system and process manager join probably won't fix this.
I'm back to the view that the 512 (or something close to that) is sitting above everything else high in ram that not allocated and not in any process/library/managers control.  So I'm back to thinking that when the process manager starts it is just not given all available ram even though the system has it available.

I did find something that looks like it might be setting this value to just some random number that some software engineer picked as "this looks big enough" and it never got updated.  So there may be absolutely no reason that the limit exists other than someone like the number and it was big enough at the time.

So I may have more to report in the not too distant future (I'm pretty busy right now so I'm a little slow on this stuff), but the good news is that I think it's getting close to being fixed, maybe.

Oh and I did find out how to get a handle to the process manager heap, in case anyone is wondering.