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Physical Adress Extension and Windows 9x

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I just wondered how much memory can my old windows use. Since i have one superharddisk at hand it will be quite possible to use it without impairing system performance.

So i just know that windows without PAE can use 4 gigs of physical memory. Lets imagine that i have rloews patch. How much memory can i use, or how big swapfile can i set?

Previously i have set swapfile to 4 gigs and system was about to fall apart :D

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I just wondered how much memory can my old windows use. Since i have one superharddisk at hand it will be quite possible to use it without impairing system performance.

So i just know that windows without PAE can use 4 gigs of physical memory. Lets imagine that i have rloews patch. How much memory can i use, or how big swapfile can i set?

Previously i have set swapfile to 4 gigs and system was about to fall apart :D

My RAM Patch allows up to 4GB of 32-Bit System RAM. In practice, motherboards limit this to 3-3.6 GB. Windows 9X can manage a total of 4GB with a maximum Swap File of 2GB. With my Patch you can have the following:

System RAM: 3GB

Swap File: 1GB

Using my 64-Bit RAMDISKS, you can place the Swap File in 64-Bit RAM.

Note, my RAMDISKs use PSE not PAE.

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if i should have 4gb of ram it will be possible to use it all without using harddisk, or what will happent if i have 4 gigs of ram and 2 gigs of swapfile...?

just thinking about possibility to maximize OS potential in this particular case.

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if i should have 4gb of ram it will be possible to use it all without using harddisk, or what will happent if i have 4 gigs of ram and 2 gigs of swapfile...?

just thinking about possibility to maximize OS potential in this particular case.

There are two limits in Windows 9X.

Total managed memory, System RAM and Swap combined, is limited to 4GB.

Swap file is limited to 2GB.

If you have 4GB of RAM, part of it is mapped to 32-Bit RAM and part of it is mapped to 64-Bit RAM. The amount depends on the motherboard, graphics device, and sometimes other devices.

Assuming it is split into 3GB and 1GB respectively, a fairly common situation, the following combination will maximize memory use without swapping to a hard drive:

The RAM Limitation Patch will support the available 3GB of 32-Bit RAM.

A 64-Bit RAMDISK, setup to hold the Swap File, will use the remaining 1GB when the 3GB of System RAM is used up.

I have written some tools to allow programs to use additional 64-Bit memory, but they would not be very useful unless you have more than 4GB of RAM.

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I have written some tools to allow programs to use additional 64-Bit memory, but they would not be very useful unless you have more than 4GB of RAM.

where can i get it?

it would be nice to see my 98se running with 8gb ram :whistle:

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I have written some tools to allow programs to use additional 64-Bit memory, but they would not be very useful unless you have more than 4GB of RAM.

where can i get it?

it would be nice to see my 98se running with 8gb ram :whistle:

I have an 8GB RAM system already running using Windows 98SE. In addition to the setup I described in my last post, I have two additional RAMDISKs using the 4GB not covered by the RAMDISK allocated to the Swap file.

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where can i get it?

it would be nice to see my 98se running with 8gb ram :whistle:

Go to RLoew's Software Homepage and visit the Prerelease and Beta Section. HTH

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also there is another limit as i know...

How much memory can assing system to a single application? In XP it is around 2gb... What about your patch?

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also there is another limit as i know...

How much memory can assing system to a single application? In XP it is around 2gb... What about your patch?

That private address space limit is inherent in Windows 32-bit design (although later NT OS's provide options to expand to 3GiB with tradeoffs).

See here for lots of good info on the Windows 98 architecture:

http://technet.microsoft.com/en-us/library/cc768198.aspx

See Memory Paging about half way down.

I would recommend reading the entire Chapter 28 through if you have the time.

It helps give a better understanding of how and why Windows 9x does what it does.

Obviously some of this article does not apply to early versions of Windows 95, like WDM.

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also there is another limit as i know...

How much memory can assing system to a single application? In XP it is around 2gb... What about your patch?

My Patch increases the amount of Physical System RAM available to Windows. It does not affect the Virtual Address assignments between User, Shared and System Memory.

By design, the User memory space is limited to 2GB. I have explored the possibility of moving these boundaries, but it appears to be hard coded extensively.

It is possible for an Application to allocate Shared or even System Arena space to approach the 4GB limit but there are many issues:

1. This memory would be locked so it could not be swapped out.

2. The memory would not be part of an Application Context so it would be Global to all Applications, so each Application or Instance of an Application would need to allocate different Virtual Addresses.

3. These Arenas are limited System Resources so using them could deplete them.

4. This Memory would not be recovered if the Application exited or crashed before releasing it.

My 64-Bit Memory SDK would not get around this issue either since, like my Patch, it provides more Physical RAM not Virtual RAM. The main benefit of the SDK is that an Application could have a lot of RAM that could be accessed by Banking

Edited by rloew
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1. This memory would be locked so it could not be swapped out.
Uhh, that's not true. Shared memory is nicely swapped out, and with 64MB or less memory you can easily swap even system DLL pages.

Moreover, mapped files reside in shared memory and basically are part of swap; and they are tracked by system, so apps using file mapping can use more than 2GB of virtual memory on 9x... Who cares?

Edited by Tihiy
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1. This memory would be locked so it could not be swapped out.
Uhh, that's not true. Shared memory is nicely swapped out, and with 64MB or less memory you can easily swap even system DLL pages.

Moreover, mapped files reside in shared memory and basically are part of swap; and they are tracked by system, so apps using file mapping can use more than 2GB of virtual memory on 9x... Who cares?

I did some experiments and confirmed that the Shared and System Arena Memory Pages CAN be swapped. I stand corrected.

Note: Many System DLLs load into Private Memory and are inherently swappable.

The Context problem still remains, so if one Application took the Maximum amount of Memory, no other Application could exceed 2GB unless they are using the SAME Memory..

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So...

The last question is about Graphics cards and the issue which caused XPs to allocate 4gigs as 3.2 gigs ram.

How much memory any windows (32bit) need?

2 gigabytes can be assigned to a single applicaton. Win98 uses up to 100mb of ram, WinXP up to 512. Rest of 4gig pool is floating in the air or is it really used for something (especially the block which is invisible in XP)?

Lately i tested vista, and its system management has finally becomed better as in XP, so i dont doubt that it can handle all memory. I am quite interested about high Hw limit of both XPs and 98Se (patched one) and the way how effectively both of them can use up system memory.

Right now it seems to me that most of Windows upgrades were unnecessary while system had less than 4 gigabytes of memory, because no application was able to gain more than 2 gigabytes from system (and thus work faster). Also it is just question if 32bit application is able to acess so much memory, or cant.

At all i am quite interested in system build on singlecore processor (AMD or Intel?) with approximately 3 or four gigabytes of memory to see how can applications perform in windows 98 and compare it with other windows based systems, with more memory available.

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So...

The last question is about Graphics cards and the issue which caused XPs to allocate 4gigs as 3.2 gigs ram.

The reason XP, and the Patched Win9X, only see 3.2GB (in your case), is that the BIOS reserves the rest of the 32-Bit Address space for Memory Mapped I/O and the BIOS ROM. In addition, the BIOS will map AGP apertures and other large PCI card I/O Spaces to this area as needed.

Rather than wasting the RAM Space, the BIOS remaps this RAM into the 64-Bit Address Space above 4GiB.

How much memory any windows (32bit) need?

2 gigabytes can be assigned to a single applicaton. Win98 uses up to 100mb of ram, WinXP up to 512. Rest of 4gig pool is floating in the air or is it really used for something (especially the block which is invisible in XP)?

Lately i tested vista, and its system management has finally becomed better as in XP, so i dont doubt that it can handle all memory. I am quite interested about high Hw limit of both XPs and 98Se (patched one) and the way how effectively both of them can use up system memory.

Right now it seems to me that most of Windows upgrades were unnecessary while system had less than 4 gigabytes of memory, because no application was able to gain more than 2 gigabytes from system (and thus work faster). Also it is just question if 32bit application is able to acess so much memory, or cant.

At all i am quite interested in system build on singlecore processor (AMD or Intel?) with approximately 3 or four gigabytes of memory to see how can applications perform in windows 98 and compare it with other windows based systems, with more memory available.

Windows 9X can use more than 100MB of RAM internally, if it is available. File Caching can use 512MB alone.

Even if an Application is limited to 2GB, running two at the same time brings you up to 4GB.

Using RAMDISKs for Swap and/or Temporary Files provides additional speedup.

On one machine, I have a 1.5GB RAMDISK that holds my Temporary Internet files. I can download 2 CD sized ISO files simultaneously.

In addition, all files are cleared upon reboot.

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On one machine, I have a 1.5GB RAMDISK that holds my Temporary Internet files. I can download 2 CD sized ISO files simultaneously.

In addition, all files are cleared upon reboot.

I use a RAMDISK of precisely 1.5 GiB in my main Win 98SE for the same reason.
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