Personal computing discussed
Moderators: renee, mac_h8r1, Nemesis
morphine wrote:Why? This enables remapping all devices' memory addresses to "above" your RAM for 64-bit OSes.
derFunkenstein wrote:I think Supreme Commander is not the application you want to use in that illustration because it was built with the LARGE_ADDRESS_AWARE
or maybe it's a great example because it's a 32-bit app that can use all 4GB as user space should it be available. Now i'm not sure. :/
Ryu Connor wrote:It's always amusing to see how this industry tends to ignore a problem until it becomes widespread.
SuperSpy wrote:Indeed, I can't wait to see what happens in 15-30 years when "OMG How do I get my machine to address more than 16 exbibytes?!" posts start appearing.
Ryu Connor wrote:SuperSpy wrote:Indeed, I can't wait to see what happens in 15-30 years when "OMG How do I get my machine to address more than 16 exbibytes?!" posts start appearing.
Somewhat sooner unless AMD64/Intel64 continue to push their address space.
Presently they only support 40bits physical (1 tebibye).
Krogoth wrote:x86-64 architect supports up to 2^64 bits.
derFunkenstein wrote:Krogoth wrote:x86-64 architect supports up to 2^64 bits.
Fixed. You were giving it 8x the address space than it really has.
bitvector wrote:No, he had it right with bytes. x86 is byte addressed. Each address refers to a byte, and each is 64 bits, which gives you 2^64 possible bytes.
If x86 was bit addressed, 32-bits would only give you 512MB of address space. Bit addressable architectures are rare: on his webpage, Andrew Morton notes that it was a pain to port gcc to the TI34010 due to this quirk.
Final Thoughts
Among all of our tests, there are three identifiable patterns, all relating to some difference between Vista and XP. Those are:
1. Vista is using more address space than XP in all situations
2. The amount of address space used with Vista seems to be related to the amount of video memory on our video card
3. XP on the other hand does not fluctuate at all, the address space usage is the same no matter what card we use.
So, it does appear from their testing that video memory for 3D apps eats up a lot more application address space than XP, and that it is variable with the amount of video ram you have on your video card.
This is not necessarily all bad, just make sure you have lots of RAM when running Vista, especially for 3D apps!
oldDummy wrote:So now I'm confused...What is the relationship between the [Virtual?] address space and the hardware ram referenced in the quote?
oldDummy wrote:Also, (at a guess) isn't XP utilizing the address space for the PCIe buss while Vista is using it to map the gfx card memory?