Author Topic: Mac OS 9.2.2 Memory Limit of 1.5 GB... Some Answers  (Read 49366 times)

Offline nanopico

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Mac OS 9.2.2 Memory Limit of 1.5 GB... Some Answers
« on: November 19, 2015, 08:21:24 PM »
So you install 2 GB of ram and OS 9.  Then you go to about this mac and you see that hey the system recognizes that there is 2GB of ram!!! And you get all excited until you notice that Mac OS takes up 512-540 MB (give or take) 
This is not new I know.  DieHard pointed the out to me and directed me towards this discussion
http://macos9lives.com/smforum/index.php?topic=2101.msg10905#msg10905

I've posted elsewhere some theory's I had while examining memory.
So using an iBook with 320 MB of ram I found that the system heap and stack along with some rom space and some other system stuff sits at the bottom of ram (starting at or around address 00002800).  Once the process manager starts it claims the rest of the memory for it's heap except for a little bit at the top which it is allocated for it's stack.
For those of you who don't know, the heap is the working memory where your data is stored and the stack is the memory where the actually executable code is stored.  Because os 9 does not have protected memory you can write apps that pretty much read anything.  With protected memory apps are usually given a virtual address space so it thinks it starts at address 0 the os then translate that to physical addresses.  The heap for the app is then marked as non-executable though on some systems you can override that ins some creative ways.
Back on track though.  So when the system boots it get's the ram size information from Open Firmware.  The memory manager I believe starts before the process manager (don't quote me on that as I haven't confirmed this yet). So the os is fully aware at this point of the 2 GB installed.  Depending on which starts first will be where the ram get's allocated to the process manager. When about this mac shows that MacOS takes 540 MB it's actually not really true.
Looking at the heaps and stack allocations, the system files are still only taking 30-40 or whatever your system uses depending on extensions and what not.
For MacOS memory usage (which is not handled by the process manager) it takes the total ram installed and subtracts what is allocated to the process manager, and assumes what is left is allocated to the system.
So that is where the number comes from.
So poking around with MacsBug you can look at what is in the ram above 1.5 gb.  Guys what there is nothing (no surprise there).  It's all initialized to zero.
So next step is to write a program to put data into memory addresses above the 1.GB limit.
Then use MacsBug to verify it is there.  If that works then it tells us that the memory is addressable and the potential of some sort of ram disk up there is possible (though not necessarily easy in any way).
Just thought I'd share this bit of info.
« Last Edit: September 10, 2016, 04:27:41 PM by DieHard »
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Offline DieHard

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Re: 1.5GB Limit (some answers)
« Reply #1 on: November 20, 2015, 09:19:07 AM »
Wow.... you kinda remind me of iMic's brother... you are going where nobody went before.. Awesome work ! :)

Offline nanopico

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Re: 1.5GB Limit (some answers)
« Reply #2 on: November 20, 2015, 09:31:32 AM »
Thanks. I just hope I can actually produce something with all my findings.
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Offline Philgood

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Re: 1.5GB Limit (some answers)
« Reply #3 on: November 20, 2015, 11:07:30 AM »
Let's get started!
Will 2016 be the year of somewhat bigger for our beloved OS9...maybe we can get the attention of some former Apple engineers to help us
*G4 MDD 1.25GHz (Single 2003)* with 2x 80Gb harddrives, 1Gb RAM, Tascam US-428 and Edirol FA-101 USB/Firewire soundcards-*iMac G3 DV 400MHz* with installs from OS 8.6-OSX Tiger on different harddrives-*Powerbook G4 1.67Ghz* with new SSD ! Love it.

Offline MacTron

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Re: 1.5GB Limit (some answers)
« Reply #4 on: November 20, 2015, 11:16:35 AM »
For MacOS memory usage (which is not handled by the process manager) it takes the total ram installed and subtracts what is allocated to the process manager, and assumes what is left is allocated to the system.
So that is where the number comes from.
So poking around with MacsBug you can look at what is in the ram above 1.5 gb.  Guys what there is nothing (no surprise there).  It's all initialized to zero.
So next step is to write a program to put data into memory addresses above the 1.GB limit.
Then use MacsBug to verify it is there.  If that works then it tells us that the memory is addressable and the potential of some sort of ram disk up there is possible (though not necessarily easy in any way).
Just thought I'd share this bit of info.

This is becoming into something really interesting ...  :)
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Offline greatinterface

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Re: 1.5GB Limit (some questions]
« Reply #5 on: November 20, 2015, 08:08:42 PM »
lets get those 2 gigs working ,just picked up a lovely 23 inch apple display for $50 on craigs list ,bad news my scripts did not copy properly on the boot disc for my "drive cloning"  aka restore project ,will have to try unstuffing on different machine

Offline nanopico

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Re: 1.5GB Limit (some answers)
« Reply #6 on: November 20, 2015, 08:47:01 PM »
Another fun update.
A. I'm still not sure how the hardware MMU plays into this whole thing.  Not sure if OS 9 initializes that differently than OS x or it has something odd to do with maybe it's using a signed int for memory address (that would be odd and not fun to break). I only mention this because hardware is also placed with in the address space accessed by the MMU and you should keep that in mind with the next part.

B.  I have a fun utility/crude app I wrote to do some memory test from with in the OS.
  I'm going to share it with anyone who want's to play with it, but first some disclaimers.
1.  It's a very crude, basic app with no error checking/handling.  Yes it's easy to crash it (and actually that's part of the intent for what I'm doing with it.
2.  The user has control of the memory it accesses. So if you put in an address that is mapped to firmware, video card, any other hardware, then it will write some data to it and it very well could break things.  Just so you know.

So this app doesn't directly cause harm unless the user enters and address that could corrupt things.

So here's what it does. 
When it loads it loads with a heap size between 512K and 1MB.
Once loaded it try's to allocated a chunk of memory that is 10 MB in size.  This is using built in system calls for memory.  Since the heap is way under 10 MB this allocation request fails which is exactly what it should do.
Next it asks the you for a memory address.  You must enter it in hexadecimal.  There is no error checking on that so if you enter a non-hex value it will probably crash on that. Since this is fairly useless of an app and more of a test I'm not going to fix that.
After you provide it an address it starts at that address and writes a 32bit integer to the address, moves to the next address writes an integer 1 larger than the previous, ...etc  until it has done this for 10 mb.
If the memory is addressed that test will pass and it will move on to read that data and compare it to what it put in.  If something doesn't match it will give you the address it didn't match.
That's it.  For memory with in the 1.5 gb range and that isn't allocated to anything this all passes as it should (being that the first one fails intentionaly. 
All this really does is determine if a specific memory address is accessible from an application without using the OS memory/process manager routines. 

So in using it I've found that with in the 1.5 GB limit or what the max ram of your machine is, all this works.   Trying to access ram above 1.5 gb fails.  Not sure why yet, but it flat out failed. So from within an application that extra 512 mb is not accessible, yet.

Also just a few other disclaimers.
Putting addresses below 60 mb or so will crash/lock up your system.  On some of my test it grey screened and locked up, some froze the display and then locked up.  In both cases it messed up macsbug enough that I couldn't even enter it.  So please use caution when using this.  I am absolutely not responsible if you brick your system using this. 

Have fun.
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Offline DieHard

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Re: 1.5GB Limit (some answers)
« Reply #7 on: November 20, 2015, 08:54:51 PM »
Gonna have to fire up a G4 this weekend and crash it a bunch of times, sounds like fun, thanks nanopico

Offline nanopico

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Re: 1.5GB Limit (some answers)
« Reply #8 on: November 20, 2015, 09:13:21 PM »
One address I can say don't use is 0x10 (16 decimal) 
It didn't really screw anything up major, but it took a few reboots before my iBook would boot up.  Have fun with it.
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Offline nanopico

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Re: 1.5GB Limit (some answers)
« Reply #9 on: November 21, 2015, 07:42:49 PM »
One small correction.
I stated that the little utility I posted tried to write 10 MB of data to a place of your choosing.
That was wrong.  The first version I wrote used a 8 bit pointer so it did write 10 MB.  The version I posted uses a 32 bit pointer, so it writes 40 MB.
Just wanted to clarify that for any one trying it.
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Offline nanopico

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Re: 1.5GB Limit (some answers)
« Reply #10 on: December 04, 2015, 08:27:07 PM »
So after further investigation I've discovered a few things.
The reason the test app I wrote couldn't access the empty ram above 1.5 GB was due to the MMU.
I'm going to over simplify this a bit but I'm going to hit the pertinent parts.
Open Firmware Starts the machine and initialized a bunch of hardware.
The device tree defines the ram sockets and provides info as to what is installed in each socket.  This is why  you see 2 GB in about this mac.
This is also why apple profiler shows the correct amount of ram in each slot.

Next the rom is loaded and starts initializing a bunch of stuff.
The first thing that starts is the resource manager, then a bunch of other stuff get's initialized.
Then a simple memory manager get's started. This initializes the stack for the system components (this is what's sitting in the lower part of ram).

Now the last few things that happen during boot right before the finder is launched is where our issue starts to happen.  Once extensions are all loaded the last thing that happens is the process manager is started.  The simple memory manager from earlier calculates what has been allocated for the various system components and the system stack and heap and all that fun stuff.  And then at the top of all that stuff is the start of ram allocated to the process manager.  When the process manager get's loaded what ever loads it is setting it's limit to 1.5 gb - the system heap and stack.  The process manager then starts it's own memory manager for allocating space to other apps with in it's heap.  When the MMU is setup it maps the physical ram address to the virtual addresses.  So virtual address 0x00000000 is physical address 0x00000000 of ram.  The MMU's mapping end's the virtual ram address space at 1.5 gb which is why access above that is limited or not available.  Where ever the MMU get's initialized during and after rom boot is the location of the code that needs to be patched.
This is why the access violation errors get thrown in my test program.


Okay so that's a bit rambly.  But the point is when the heap get's allocated for the process manager is when the 1.5 gb limit is being set so it starts to narrow down the search and what needs to be modified to get this limit raised.

I also found another interesting tidbit in working through this.  There is something mapped in the upper part of ram near the 4GB mark.  This would be the absolute physical limit and as the MMU's in these machines are 32bit there will be no way to go above that.  I'm suspecting that the stuff up by the 4gb limit are the address to the hardware registers (the ports and address of the graphics card for example).

I'll stop rambling now.
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Offline GaryN

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Re: 1.5GB Limit (some answers)
« Reply #11 on: December 04, 2015, 11:31:26 PM »
Ramble on anytime, man. Possibly a few of us blockheads might learn something!

Offline mrhappy

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Re: 1.5GB Limit (some answers)
« Reply #12 on: December 05, 2015, 04:13:29 AM »
Yes indeed!! ;D

Offline nanopico

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Re: 1.5GB Limit (some answers)
« Reply #13 on: December 06, 2015, 08:29:36 AM »
Except some of my ramblings are incorrect while I figure this stuff out. (though they are getting more accurate the further down the rabbit hole I go).
Ramble on anytime, man. Possibly a few of us blockheads might learn something!

I think I might have a possible explanation for the 1.5 GB limit.
By the time any machines could physically handle 2GB of ram, OS X was already in the works.
It was probably though as a low priority to re-write/patch the memory manager/process manager to allow more ram.  Why there was a limit in the first place is beyond me.
But what lead me to the 1.5 GB limit reason is the 9600.  Even though official support was 756 MB apple was probably aware that it could handle 1.5 GB. At that time any of the next generation OS's where in such early stages there was no foreseeable future.  Customers would probably complain if they couldn't use all the ram so the parts of the os that handle that would have been updated and the 1.5 GB limit was probably chosen for that reason.

Again just speculation, but after having worked on all sorts of dev project the past 15 years I can say these things do happen a lot with out much forward thought.



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Offline nanopico

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Re: 1.5GB Limit (some answers)
« Reply #14 on: December 07, 2015, 12:43:16 PM »
So I've been studying the CPU registers that control the MMU (memory management unit).
So the Block Address Translation tables are pointed to by CPU registers. These control the mapping of the addresses from what applications see to physical hardware address. They are only accessible from code executing in the Supervisory context of the processor (usually this is the os) and the guest process (user programs) as some access to this.  Not all OS's use the guest process for running applications though.  This might actually be the case with the Mac OS as that is usually needed to provide protected memory (which will all know is non-existent in OS 9) but I really don't know right now the reality of this.  At a minimum I can read most of those.  So next step is reading in these tables and seeing what's mapped where and this will give a more definitive idea of what is located where in memory.

One small kill joy though.  The PPC spec that explains the MMU registers does have some notes about 64bit cpu's (the G5).  So some of the Opcodes for accessing the registers are explicitly not supported on 64bit cpus even if the cpu is running in 32 bit mode.  In OS X the memory management routines probably account for this which is why on the G5 you could have more than 4GB of ram in a 32bit os.  OS 9 probably did depend on some if not all of these 32bit only opcodes and registers.  So we now have two major hardware roadblocks to overcome if there is ever any hope of G5 support.  1. the mmu opcodes/registers and 2. the UniNorth 3 bridge.

Also in looking through this I looked more at the PVR and PIR registers.  (these are the Processor ID and Processor Version).
The cpu upgrades that update open firmware through nvram scripts to get newer g4 cpus working, are modifying these.
So now that I know the registers I can find where Mac OS checks those registers.  Then it should help in looking for the list of values the register is compared against to update that to get more cpu's support with out nvram scripts or changing values in open firmware.

If it ain't broke, don't fix it, or break it so you can fix it!

Offline DieHard

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Re: 1.5GB Limit (some answers)
« Reply #15 on: December 07, 2015, 02:08:02 PM »
I live for these updates on the progress, and appreciate all the details

Thanks... :)

Offline nanopico

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Re: 1.5GB Limit (some answers)
« Reply #16 on: December 07, 2015, 02:56:04 PM »
I live for these updates on the progress, and appreciate all the details

Thanks... :)

Thanks.  I'm starting to get to the point where it is shifting from theoretical to actual.  I'm definitely running into things that I have a hard time understanding the reasoning for, which make's it a little hard to explain.  But man this is getting to be real fun.
If it ain't broke, don't fix it, or break it so you can fix it!

Offline nanopico

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Re: 1.5GB Limit (some answers)
« Reply #17 on: December 16, 2015, 06:32:51 AM »
Tiny update  here.

Macsbug thinks there is no mmu installed on g3's and g4's. This would indicate that it might not be running in the supervisor level of the cpu (though as a low level debugger I find that kind of hard to believe).  This makes it kind of hard to use to view the mmu registers which control all the pages and maps and segments and fun stuff.  It might just be that macsbug (being that it was originally for the 68k macs) just doesn't know the instructions or how to access the mmu on powerpc's.

So now I have to write some assembly code to read the mmu registers and dump them out.
Once I have something working there I might ask if any one can run it on their machines and provide me the output so I can see how different configurations are mapped?  I have several machines I will run it on, but the more the merrier right?
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Offline Protools5LEGuy

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Re: 1.5GB Limit (some answers)
« Reply #18 on: December 16, 2015, 07:54:40 AM »
Count with me for any test in my 867 dual with 2Gigs of RAM
Looking for MacOS 9.2.4

Offline Veneteaou

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Re: 1.5GB Limit (some answers)
« Reply #19 on: December 16, 2015, 01:15:57 PM »
I've can throw in:

- G3 Clamshell iBook 300MHZ
- G4 867MHz Powerbook G4
- G3 800/900MHZ iBook
- G3 350MHz Blue & White tower

I can test it on all of those.

Offline GaryN

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Re: 1.5GB Limit (some answers)
« Reply #20 on: December 16, 2015, 01:38:54 PM »
I'm here with:

2003 MDD M8570
Titanium Powerbook  1Ghz  A1025
Powerbook G3 Lombard M5343

Offline nanopico

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Re: 1.5GB Limit (some answers)
« Reply #21 on: December 16, 2015, 07:37:22 PM »
Awesome guys.
With the holidays and such coming up (and my kid not having school for a week or so, making me daycare for a week!) I probably won't have anything until the beginning of January.
I'll let you know when I have something ready.
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Offline Protools5LEGuy

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Re: 1.5GB Limit (some answers)
« Reply #22 on: May 03, 2016, 08:56:02 PM »
Looking for MacOS 9.2.4

Offline DieHard

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Re: 1.5GB Limit (some answers)
« Reply #23 on: May 04, 2016, 04:05:20 PM »
PT5,

Thanks for the list :)

But under OS9 we are limited to 1.5 GB on ALL Models...

http://macos9lives.com/smforum/index.php?topic=2101.msg10763#msg10763

Offline Mat

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Re: 1.5GB Limit (some answers)
« Reply #24 on: May 04, 2016, 06:28:10 PM »
PT5,

Thanks for the list :)

But under OS9 we are limited to 1.5 GB on ALL Models...

But that doesn´t change the fact that there are some Macs that allow 2 GB for other Operating Systems. And that is exactly what the list is about: Macs that boot Mac OS 9 AND allow 2GB Ram.

Offline DieHard

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Re: 1.5GB Limit (some answers)
« Reply #25 on: May 04, 2016, 09:09:06 PM »
Just to clarify for the members new to PPC G4 Macs...

YES, many can physically handle an install of up to 2 GB RAM, and YES the OS will show 2 GB RAM, and YES, OSX can utilize the entire 2 GB, but unfortunately Mac OS 9 can only utilize 1.5 GB of the physical 2 GB RAM.

Offline Protools5LEGuy

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Re: 1.5GB Limit (some answers)
« Reply #26 on: May 04, 2016, 09:23:52 PM »

But under OS9 we are limited to 1.5 GB on ALL Models...

http://macos9lives.com/smforum/index.php?topic=2101.msg10763#msg10763



Built-In Memory. 1.99. I want to know more about that supersized Mac OS System itself using 811.9 MB instead of 68.1MB. I am keeping the faith in that we will recover some of this memory back to the user. In fact "256" Megs are taken for the RAM disk.

I can always pull out memory to make 1.5 or even 1 Gig. of RAM, but OSX benefits from that extra 0.5 RAM.  We have 4 slots.

On the AL 1.0 GHz 17" Powerbook you have only 2 slots.

We should look if having more than 1.5 Gigs of RAM we make the system more prone to crash.

Also if 1kWindows test shows a slower system when using with more than 1.5 Gigs of RAM.

Imagine we can use that nanopico BootX loader to fool OS9 think it only has 1.5 and the virtual RAM Disk is made before loading OS9. We could call it "2 Gigs patch for OS 9" or "512 Meg RAM disk for 2 Gigs RAM". The benefits of that neglected 0.5 Gig in a RAM Disk for DAW or Photoshop would do wonders. Probably I am delusional with the possibilities.
 
OFFTOPIC: I hate to pull off memory. It reminds me an x86 P4 triple boot I had with W'98 (Needed less than 768 Megs), XP + XXX 10.4.11. 


Looking for MacOS 9.2.4

Offline DieHard

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Re: 1.5GB Limit (some answers)
« Reply #27 on: May 04, 2016, 09:38:32 PM »
HA ! That screenshot always cracks me up; 811.9 MB for the Mac OS, Mactron would have a heart attack if that was accurate !

He works for days if he wastes .000002 MB and re-writes extensions... LOL

Offline Protools5LEGuy

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Re: 1.5GB Limit (some answers)
« Reply #28 on: May 04, 2016, 09:57:51 PM »
I would pay an 800 Meg Mac OS system TAX gladly if it would allow true multitasking, protected memory, USB 2.0 and FW-800.  :D

In the meantime, it makes sense to have under 1.5 G of RAM for a pure OS9 setup.
Looking for MacOS 9.2.4

Offline nanopico

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Re: 1.5GB Limit (some answers)
« Reply #29 on: May 05, 2016, 06:17:21 AM »
I had a new stupid theory earlier this week on this.
Some of the pre-g3 macs that are supported in 9 had 12 ram slots.  They official supported 128 MB dims but others found that 256 ones worked.
This only equates to 768 mb though. I think Apple probably knew that 256 would technically work, but for whatever reason stated only 128 would work.  With 256 used in each slot you get 1.5 GB.  I think that this is the driving force behind the reason for the limit.  That or I'm just crazy.  Still doesn't help solve the problem though.
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Offline MacTron

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Re: 1.5GB Limit (some answers)
« Reply #30 on: May 05, 2016, 08:18:47 AM »
HA ! That screenshot always cracks me up; 811.9 MB for the Mac OS, Mactron would have a heart attack if that was accurate !

He works for days if he wastes .000002 MB and re-writes extensions... LOL

 ;D ;D ;D ;D

Not at all. This is a very known picture. It only has to do with the Finder way to compute memory. It clearly knows that there is 2 GB installed, but it only can use ( RAM addressable ) 1.5 GB.
Please don't PM about things that are not private.

Offline nanopico

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Re: 1.5GB Limit (some answers)
« Reply #31 on: May 05, 2016, 08:21:22 AM »
HA ! That screenshot always cracks me up; 811.9 MB for the Mac OS, Mactron would have a heart attack if that was accurate !

He works for days if he wastes .000002 MB and re-writes extensions... LOL

 ;D ;D ;D ;D

Not at all. This is a very known picture. It only has to do with the Finder way to compute memory. It clearly knows that there is 2 GB installed, but it only can use ( RAM addressable ) 1.5 GB.

Because the Mac OS usage is calculated by the total ram - what the process manager has allocated to it. Now how to change that allocation and what other ramifications that will have are the problem.
If it ain't broke, don't fix it, or break it so you can fix it!

Offline DieHard

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Re: 1.5GB Limit (some answers)
« Reply #32 on: May 05, 2016, 09:44:35 AM »
Sorry, lost a little in the translation, I KNOW it's NOT accurate, but if it was.... we would have about 10 threads explaining what extensions/control panels to turn off :)

Offline nanopico

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Re: 1.5GB Limit (some answers)
« Reply #33 on: May 10, 2016, 07:46:30 PM »
Quick update here.
I found some older documentation on MacsBug that outlined the mmu and memory map info.
It was older documentation for some of the earlier OS, but the commands in MacsBug haven't changed other than there are some PPC specific alternatives that require that (such as the dissembler).
So between that and system calls asking to for logical to physical translation I can identify a clearer vision of the address space and where the ram sits with in it to find out what regions of physical ram are mapped to what logical address and figure out exactly what parts of the ram it is not using.  Possibly then sending a couple instructions to the MMU to ask it to map the missing ram.  Crazy idea yes, but moving in the right direction.
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Offline Protools5LEGuy

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Re: 1.5GB Limit (some answers)
« Reply #34 on: May 10, 2016, 10:10:18 PM »
The folks from sheepshaver will thank any info on MMU.
Looking for MacOS 9.2.4

Offline ELN

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Re: 1.5GB Limit (some answers)
« Reply #35 on: May 27, 2016, 08:56:56 PM »
Anyone ever used the Potatoswatter's Ephemerboot? It gave you a bootable RAM disk on NewWorld systems. I quote from the docs:
Quote
This also gets around basic limitations in the Mac OS, like the 1.5 gig limit. A 500 meg Ephboot disk should let a 2 gig machine use all of its memory.

Offline Protools5LEGuy

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Re: 1.5GB Limit (some answers)
« Reply #36 on: May 28, 2016, 05:43:39 AM »
https://groups.google.com/forum/#!topic/comp.sys.mac.programmer.help/UH78zG9cmPA
Quote
Current Multiprocessing SDK from Apple contains
version 1.5d16 of PowerMacInfo tool. Undertstand
there is a version 1.7d5 (post by Rene A. Vega
on 10-25-2001). Does anyone know where this can
be downloaded ?

Also, where might I find additional documentation
on the nanokernel (if any exists) ?

Thanks for any help, Nick Burgoyne    14 Feb 2003
<sbrbN...@cats.ucsc.edu>

Quote
It's up to you to figure what's going on inside the nanokernel. You
might have fun with the source from my hack Ephemerboot, at
http://homepage.mac.com/potswa/source .

You could ask Rene for 1.7d5. Or you could ask me.

   - Potatoswatter
« Last Edit: May 28, 2016, 05:54:26 AM by Protools5LEGuy »
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Offline Philgood

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Re: 1.5GB Limit (some answers)
« Reply #37 on: May 28, 2016, 05:48:03 AM »
Please post this little app, tool, whatever it is...
*G4 MDD 1.25GHz (Single 2003)* with 2x 80Gb harddrives, 1Gb RAM, Tascam US-428 and Edirol FA-101 USB/Firewire soundcards-*iMac G3 DV 400MHz* with installs from OS 8.6-OSX Tiger on different harddrives-*Powerbook G4 1.67Ghz* with new SSD ! Love it.

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Re: 1.5GB Limit (some answers)
« Reply #40 on: May 28, 2016, 10:06:01 AM »
Because the Mac OS usage is calculated by the total ram - what the process manager has allocated to it.

allocated as the max, as long as not some other apps are asking for this RAM to use, then it is the min.
"It is true that the "pre-emptive multitasking" advantage present in OS X can be illustrated by downloading CD-ROM ISOs and rendering chaos theory formulas while simultaneously instant messaging and posting on FaceBook what you ate... but in reality, what did you create?"
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Offline DieHard

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Re: 1.5GB Limit (some answers)
« Reply #41 on: May 28, 2016, 11:19:15 AM »
Quote
This also gets around basic limitations in the Mac OS, like the 1.5 gig limit. A 500 meg Ephboot disk should let a 2 gig machine use all of its memory.

As we know, the apple RAM disk memory used pads itself to the System memory used and is thus, worthless in our quest for the missing .5 GB, but if the quote above is real that would be amazing... this means the wheel we are engineering has already been built.  We need to get this app. and test it NOW !

Offline nanopico

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Re: 1.5GB Limit (some answers)
« Reply #42 on: May 29, 2016, 07:00:23 AM »
Because the Mac OS usage is calculated by the total ram - what the process manager has allocated to it.

allocated as the max, as long as not some other apps are asking for this RAM to use, then it is the min.

I'm not sure I follow you, but The Mac OS Usage I am referring to is the amount of ram allocated to Mac OS when you view About This Computer.  It's not calculated by the actual usage.

Quote
This also gets around basic limitations in the Mac OS, like the 1.5 gig limit. A 500 meg Ephboot disk should let a 2 gig machine use all of its memory.

As we know, the apple RAM disk memory used pads itself to the System memory used and is thus, worthless in our quest for the missing .5 GB, but if the quote above is real that would be amazing... this means the wheel we are engineering has already been built.  We need to get this app. and test it NOW !

From what i have seen with this, it id ram disk that it mapped to look like a physical hard drive and the ram used by it is not visible to the OS.  The ram disk has to be used to boot the system.  So you in theory would get be able to use all the memory, but at least 512 MB would have to be a ram disk that the system boots from.   It's a rather neat system and I'm trying to wrap my head around it's workings to see what we can learn from it, but it doesn't seem to patch the system memory manager at all so we are still limited to 1.5 GB max allocation once booted.  But once booted the system will still load it's self now within that 1.5 GB and not outside it like it currently does.  So actually in theory, going this route can cause the usable memory to be less than not using this tool/utility/application.
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Offline nanopico

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Re: 1.5GB Limit (some answers)
« Reply #43 on: June 13, 2016, 11:11:46 AM »
Knowledge attained regarding getting to 2GB.
Just a small update.
So I found some bit's poking around and reading documentation.
So what we know is that the process manager get's allocated 1.5GB of ram and the rest is the system.  This is calculated by the size of the actual memory minus that which is allocated to the process manager.
The process manager is installed at the top of RAM and it's heap grows down, just like every other application.
The system is placed at the bottom of RAM and it's heap grows up.
The reason for this is so that the system doesn't hit a hard limit if it needs to grow. So if it didn't get enough allocated early on and it grows it hits the bottom of RAM and that probably isn't good.
If the system heap needs to grow it takes it from the process manager by shrinking  it and then expanding the system heap.  When the system heap can shrink it does so and then grows the process manager's heap.  Generally you won't ever actually this though.  The system heap really only grows during boot while it's loading extensions.
What I didn't realize is that there is a dummy heap between the two of them. So at the end of the process manager heap is a heap header and then a small empty block.  This dummy heap is supposedly what's moved around to shift the memory between the two heaps.

Supposedly the dummy heap is there to hide some of the aspects of the process manager from things like macsbug.
So in theory if one could find the function location of the function that does the dynamic resizing then one could create an extension
that checks ram and runs that function and boom, you get use of all ram!

This is just a theory. Reality doesn't always align correctly.  It still doesn't explain why the process manager only get's 1.5 GB when more is available. 
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Offline Metrophage

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Re: 1.5GB Limit (some answers)
« Reply #44 on: June 13, 2016, 11:38:20 AM »
Thanks for your work and sharing of these insights!

Offline MacTron

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Re: 1.5GB Limit (some answers)
« Reply #45 on: June 13, 2016, 12:22:25 PM »
This is just a theory. Reality doesn't always align correctly.  It still doesn't explain why the process manager only get's 1.5 GB when more is available.

The whole 32 bits memory space was designed when 1MB of RAM was a lot of RAM :) . This 1.5 GB limit was taken later, to avoid interfering with other addressable directions with others uses. ... Probably.
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Offline nanopico

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Re: 1.5GB Limit (some answers)
« Reply #46 on: June 13, 2016, 12:35:16 PM »
This is just a theory. Reality doesn't always align correctly.  It still doesn't explain why the process manager only get's 1.5 GB when more is available.

The whole 32 bits memory space was designed when 1MB of RAM was a lot of RAM :) . This 1.5 GB limit was taken later, to avoid interfering with other addressable directions with others uses. ... Probably.

I would completely agree and believe this to be true as well. 
I was trying to figure out if the limit exists due to an addressing method where the page size is the limiting factor, but I have not found any indication of that or any bit pattern to support that yet.
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Offline nanopico

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Re: 1.5GB Limit (some answers)
« Reply #47 on: June 27, 2016, 07:18:20 AM »
I've found something really really cool (well to me it is).
So the System Heap grows up and the Process Manager Heap grows down.  This would be because they share a boundary and the process manager will be less likely to have to have anything at the bottom of it's heap as it loads programs at the top and moves down and heaps in the applications also grow down (the system heap is the only one that grows up).
There are a set of function exported from the memory manager for shrinking and expanding the heap in both the system and process manager.
These are private methods as normal application should never call them. 
When the process manager is started it looks to a resource for it's size (just like any other application with it's minimum and preferred sizes).
Once the process manager is set up the system heap is grown to meet it and then they proceed to have a wonderful relationship where they have little application children until they are both terminated.  Ok jokes aside. 
So now that I know those functions I can start to look for the resource to set the size.  Modify that and if all my assumptions are correct, then we are in business for gaining back most of that 512 MB (except for that actually used by the system heap).
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Re: 1.5GB Limit (some answers)
« Reply #48 on: June 27, 2016, 08:51:16 AM »

Once the process manager is set up the system heap is grown to meet it and then they proceed to have a wonderful relationship where they have little application children until they are both terminated.

now THAT I understand!! ;D ;D ;D

Offline MacOS Plus

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Re: 1.5GB Limit (some answers)
« Reply #49 on: June 27, 2016, 01:31:50 PM »
  I seem to recall there being a physical performance limit of PC133 RAM that capped it at 1.5GB.  Do you think the OS limit might just be a legacy holdover of that, so maintaining compatibility with most of the G4 systems wasn't complicated by the arrival of the DDR-based systems?  In any other respect the cap would look arbitrary.

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Re: 1.5GB Limit (some answers)
« Reply #50 on: June 27, 2016, 08:10:22 PM »
  I seem to recall there being a physical performance limit of PC133 RAM that capped it at 1.5GB.  Do you think the OS limit might just be a legacy holdover of that, so maintaining compatibility with most of the G4 systems wasn't complicated by the arrival of the DDR-based systems?  In any other respect the cap would look arbitrary.

I'm not sure I have ever heard of PC133 having some sort of a a 1.5GB limit.
I know I've got an older server sitting my basement that used PC133 that oddly enough has 2 sticks of 1GB each in it with out issue.

I think the limit is arbitrary at this time, and more likely is some sort of hold over from bank switching and page size related to the pre G3 power macs that had 6 dimm slots.
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Re: 1.5GB Limit (some answers)
« Reply #51 on: June 27, 2016, 11:37:50 PM »
  Yes, one way or another I'm sure it's a compatibility holdover.  I suppose we should keep in mind that we might break support in some machines by tinkering with this.  Not that it will be of concern to the majority of the users who would want to take advantage of removing the RAM cap since they are more than likely going to be using the later more powerful models anyway.  I'm more curious to know just from an information standpoint if this happens and what machines might be affected and why.

Offline nanopico

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Re: 1.5GB Limit (some answers)
« Reply #52 on: June 28, 2016, 06:08:34 AM »
  Yes, one way or another I'm sure it's a compatibility holdover.  I suppose we should keep in mind that we might break support in some machines by tinkering with this.  Not that it will be of concern to the majority of the users who would want to take advantage of removing the RAM cap since they are more than likely going to be using the later more powerful models anyway.  I'm more curious to know just from an information standpoint if this happens and what machines might be affected and why.

The breaking stuff is what concerns me or if it become unstable or something.
My intent is that if this get's figured out an extension can be made so that you only enable it if you need it and know it works for your setup.
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Offline MacOS Plus

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Re: 1.5GB Limit (some answers)
« Reply #53 on: June 28, 2016, 09:54:37 AM »
  Yes, one way or another I'm sure it's a compatibility holdover.  I suppose we should keep in mind that we might break support in some machines by tinkering with this.  Not that it will be of concern to the majority of the users who would want to take advantage of removing the RAM cap since they are more than likely going to be using the later more powerful models anyway.  I'm more curious to know just from an information standpoint if this happens and what machines might be affected and why.

The breaking stuff is what concerns me or if it become unstable or something.
My intent is that if this get's figured out an extension can be made so that you only enable it if you need it and know it works for your setup.

  This is definitely the best approach.  I found mention of the PC133 issue I was talking about.  It's buried in the text of this web page:

http://etutorials.org/Misc/pc+hardware+tuning+acceleration/Chapter+4+Main+Components+and+the+Optimal+Choice/Motherboards/

  The relevant text is as follows - "PC133 specifications recommend a limit of three DIMM or six banks at 133 MHz (The maximum memory in this configuration is 1.5 GB)."  As I remember it you can run into timing and bandwidth issues if you try to physically go beyond this configuration.  It's not a guaranteed failure but was enough of a potential problem to be officially mentioned in the spec.  A lot of PC motherboards from the time period (when PC133 support was introduced) reduced their DIMM slot count from four to three to prevent the end user from making this mistake.  You could have more than 1.5GB reliably installed if you ran it at a 100MHz bus speed, which was possible in certain motherboards with switchable memory or shared memory/CPU bus speed settings in the BIOS.

  Obviously the arrival of DDR eliminated this issue, but by then it was probably deemed not worth fixing in OS 9 because it would have opened a huge can of worms.  I know that OS 9 can't even properly identify the type of some of my DDR DIMMs and erroneously claims they are PC133 in System Profiler, which is a very weird thing for it to do in a DDR-only architecture.  (It also claims that one of the stock Apple PC2100 DIMMs that came with one of my Xserves is actually "PC2600".)

  Have you ever wondered why the Powermac G4 "Digital Audio" and "Quicksilver" are the only G4 models with only three RAM slots?  Well they're the only ones built around PC133 memory.  They can't take more than 1.5GB RAM by design so they can't benefit from removing the software limitation.  The "AGP", "Gigabit Ethernet", "MDD" and "Xserve" will be the only machines we can realistically target for greater than 1.5GB.  I'm not sure what would have to be done to effectively test for good behaviour in these systems.  Some of the guys using a lot of software DAW processing might be able to push the limits.  I recall mention though that there is a 1GB-per-application maximum allocation unit in OS 9 also.

  One final note, the four RAM slots in the AGP and Gigabit Ethernet G4s likely were not ever intended for installing greater than 1.5GB.  The cost of larger DIMMs at the time, particularly if bought through Apple, was prohibitively expensive to many users.  The slots were there to make the most of lower capacity DIMMs.  This lets me make good use of the vast pile of 64MB, 128MB and 256MB DIMMs I kept around after they were pulled from other upgraded PC systems.  Most of my OS 9 and 8.6 machines don't get enough serious use to require a lot of RAM anyway.

Offline nanopico

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Re: 1.5GB Limit (some answers)
« Reply #54 on: June 28, 2016, 10:22:52 AM »
And I do believe we have a definitive answer!!!
Thank you!

Just to add to this as evidence.  The G4's had 4 PC100 slots up to the Digital Audio which used PC133 and had only 3 slots probably for the exact reason identified by MacOS plus. 

Documentation in Inside Macintosh hints that the OS on 32 bit platforms can support up to 4 GB of ram. (Yes I know that's the limit of the address space, but the document indicates most of that could be used by an application).

So the Digital Audio and Quick Silver machines have the physical limitation of 1.5 GB.

So it might actually be simple to get that extra 512MB back.
Would best be done as an extension and stress tested to ensure stability.
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Offline MacTron

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Re: 1.5GB Limit (some answers)
« Reply #55 on: June 28, 2016, 10:35:55 AM »
I recall mention though that there is a 1GB-per-application maximum allocation unit in OS 9 also.
This is a Myth. May Be true for some apps but not in general. I have used Cubase with 1.4 Gb or RAM for years without issues:


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 :)
« Last Edit: June 28, 2016, 10:48:34 AM by MacTron »
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Re: 1.5GB Limit (some answers)
« Reply #56 on: June 28, 2016, 09:09:28 PM »
  That's awesome, MacTron!  I'm actually quite interested in dedicating a machine to software sampler instruments.  This probably is just about the best task for pushing the limits of RAM and CPU.  I'll have to try this eventually with one of my three MDDs.  I could probably even MIDI-sync multiple machines if I want to really go nuts.  Did you have to manually allocate all that RAM in the app dialog box or does it just expand on its own as it needs it?

  I have a G4 Sawtooth, MDD, MDD FW800 and Xserve Tray-load, plus a Gigabit Ethernet motherboard I plan to get running also.  This means I should be able to test 2GB RAM on all possible G4 systems when the time comes.  (I guess except for the Xserve Slot-load which is still a work in progress for OS 9.  Not sure I'm interested enough to bother buying one of those.)

Offline DieHard

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Re: 1.5GB Limit (some answers)
« Reply #57 on: June 29, 2016, 10:02:12 PM »
Quote
Did you have to manually allocate all that RAM in the app dialog box or does it just expand on its own as it needs it?

CMD-I manually... like Mactron I have set mine very high for Cubase (in my tips I recommend 400,000), but I never tried going past 800,000 (.8GB).

Hmmmmm  :o

Offline nanopico

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Re: 1.5GB Limit (some answers)
« Reply #58 on: June 30, 2016, 07:26:06 AM »
Did a little further research last night.
I'm still fairly positive it's due to some hardware limitation at some point that just never got updated in code, but I don't think the actual limit is due to the PC133 limitation as this has been in there long before that.
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Re: 1.5GB Limit (some answers)
« Reply #59 on: June 30, 2016, 09:19:22 AM »
  I just figure that with OS X well-established by the arrival of the MDD, Apple saw no incentive to build in a workaround even if it was possible in OS 9.  Most users didn't need more than 1.5GB of RAM and the benefit would be available to a relatively limited number of machines anyone would have still been willing to spend money on upgrading.  The permanent limitation of the PC133-based machines and the commitment to the transition to OS X would have made cutting off development on the issue an easy financial decision for Apple.

  I agree that the PC133 models shouldn't have any bearing on the OS code as it stands.  It's unlikely any change you make to the code could exclusively break support for those machines.

Offline nanopico

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Re: 1.5GB Limit (some answers)
« Reply #60 on: July 14, 2016, 05:03:35 PM »
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.
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Offline Texas_RangerAT

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Re: 1.5GB Limit (some answers)
« Reply #61 on: July 15, 2016, 05:10:30 AM »
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.

Offline geforceg4

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Re: 1.5GB Limit (some answers)
« Reply #62 on: August 24, 2016, 03:12:00 PM »
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
« Last Edit: August 24, 2016, 03:27:12 PM by geforceg4 »

Offline DieHard

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Re: 1.5GB Limit (some answers)
« Reply #63 on: August 24, 2016, 04:44:37 PM »
Quote
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 :)


Offline MacOS Plus

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Re: 1.5GB Limit (some answers)
« Reply #64 on: August 24, 2016, 04:50:41 PM »
  Actually, we're all just doing it for MacTron! ;)

Offline DieHard

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Re: 1.5GB Limit (some answers)
« Reply #65 on: August 24, 2016, 04:58:46 PM »
  Actually, we're all just doing it for MacTron! ;)

Yes, I second that :)

Offline geforceg4

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Re: 1.5GB Limit (some answers)
« Reply #66 on: August 24, 2016, 06:42:21 PM »
  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?
« Last Edit: August 24, 2016, 06:53:59 PM by geforceg4 »

Offline geforceg4

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Re: 1.5GB Limit (some answers)
« Reply #67 on: August 24, 2016, 07:09:51 PM »
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  ;D

« Last Edit: August 25, 2016, 12:12:56 AM by geforceg4 »

Offline nanopico

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Re: 1.5GB Limit (some answers)
« Reply #68 on: August 24, 2016, 08:30:18 PM »
So if we accomplish this then do we get elevated to the "real pros" category? ::)
If it ain't broke, don't fix it, or break it so you can fix it!

Offline geforceg4

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Re: 1.5GB Limit (some answers)
« Reply #69 on: August 25, 2016, 12:19:51 AM »
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..


Offline GaryN

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Re: 1.5GB Limit (some answers)
« Reply #70 on: August 25, 2016, 12:35:31 AM »
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  ;D

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

Offline geforceg4

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Re: 1.5GB Limit (some answers)
« Reply #71 on: August 25, 2016, 01:07:23 AM »
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

Offline DieHard

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Re: 1.5GB Limit (some answers)
« Reply #72 on: August 25, 2016, 08:32:56 AM »
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.

Offline MacTron

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Re: 1.5GB Limit (some answers)
« Reply #73 on: August 25, 2016, 08:40:36 AM »
  Actually, we're all just doing it for MacTron! ;)

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

THANK YOU !

LOL

 ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D
Please don't PM about things that are not private.

Offline DieHard

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Re: 1.5GB Limit (some answers)
« Reply #74 on: August 25, 2016, 08:48:45 AM »
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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 :)