Memory Usage Issue

[Dux]

I was confused by the client 32-bit technical limit people are mentioning. A 32 unsigned word has a maximum value of 4,294,967,295 which when converted to GBytes is 4.0GB.

With the technical limitations of Windows 32bit OS this is capped at 3.6GB of usable RAM so that rules out any OS limitation. If memory serves the PS3 has 256MB allocated to the System and 256MB allocated to graphics processing giving us a 0.5Gb Physical RAM limit however I do not understand how the PS3 MMU works as is pretty clear in my speculation below.

[Wild Speculation]
The Cell processor inside the PS3 has 8 cores. If the memory manager in the PS3 uses virtual memory addressing we may have a maximum virtual address space of 256MB * 8 which is 2.0GB.

This is reasonably close to this mysterious 1.8GB limit which people are observing.

Of course I could be talking out of my rear end, shame there aren't any PS3 programmers around who could comment on this preferably ones who knows how SE actually made the client generic between PS3 and PC.
[/Wild Speculation]

To me, in my relatively uneducated understanding of the magical ways of game creation, there is no immediatly obvious reason for this seemingly arbitrary cap in the consumption of physical RAM.

The fact that we are actually consuming 1.8GB of RAM is much more worrying to me given the huge amounts of DDR5 available on most modern graphics cards. The system should be pushing out the work to the GPUs over the CPU but apparently this isn't happening as I can't imagine what the CPU could possibly be processing that requires GBs of RAM.