PCSX2 Documentation/Virtual Memory: Difference between revisions
PCSX2 Documentation/Virtual Memory (view source)
Revision as of 23:51, 8 January 2015
, 8 January 2015no edit summary
(Created page with "''Originally written by ZeroFrog'' The Playstation 2 uses co-processor 0 to implement virtual paging. Even without COP0, the Playstation 2 memory map is pretty complex and th...") |
No edit summary |
||
| Line 14: | Line 14: | ||
Well, the OS also uses virtual memory. In fact, every process has its own special virtual memory driven by a real hardware TLB. If we could get away by mapping the 4Gb PS2 memory map onto the process's virtual memory, we could eliminate the need for the software translation (Figure 1). Looking at the virtual manipulation functions Windows XP offers, there are two major problems with this: | Well, the OS also uses virtual memory. In fact, every process has its own special virtual memory driven by a real hardware TLB. If we could get away by mapping the 4Gb PS2 memory map onto the process's virtual memory, we could eliminate the need for the software translation (Figure 1). Looking at the virtual manipulation functions Windows XP offers, there are two major problems with this: | ||
[[File: | [[File:vmem]] | ||
1 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). | 1 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). | ||