PCSX2 Documentation/Virtual Memory: Difference between revisions

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	#WindowsXP reserves more than half the address space for OS specific stuff. A good amount is also reserved for all of Pcsx2's working memory, executable code, and plugins (especially ZeroGS). It looks like we are left with less than 1.5 Gb of address range to implement the 4Gb PS2 memory map. Note that this problem doesn't exist on 64bit operating systems where the address range is practically... infinite (don't quote me on this 20 years down the road).		#WindowsXP reserves more than half the address space for OS specific stuff. A good amount is also reserved for all of Pcsx2's working memory, executable code, and plugins (especially ZeroGS). It looks like we are left with less than 1.5 Gb of address range to implement the 4Gb PS2 memory map. Note that this problem doesn't exist on 64bit operating systems where the address range is practically... infinite (don't quote me on this 20 years down the road).

	#Playstation 2 allows more than one virtual page to point to the same physical page, Windows XP doesn't (I don't know about Linux). Assume that PS2 address 0x1000 points to the same physical page as address 0x0000, each page is 4Kb. Now a write occurs at 0x1000. The game can retrieve that same value just by reading from 0x0000. In Windows XP, this has to be two different pages; so unless some clever solution/technology is discovered, we could kiss our VM dreams goodbye.		#Playstation 2 allows more than one virtual page to point to the same physical page, Windows XP doesn't (I don't know about Linux). Assume that PS2 address 0x1000 points to the same physical page as address 0x0000, each page is 4Kb. Now a write occurs at 0x1000. The game can retrieve that same value just by reading from 0x0000. In Windows XP, this has to be two different pages; so unless some clever solution/technology is discovered, we could kiss our VM dreams goodbye.