What would devs have to do to customize for the Xenos?

[pc999]

If you're going to nickel and dime the memory allocation, don't forget to add 10 MB of EDRAM.

Why count the eDRAM? It's exclusively allocated for framebuffer and Z/Stencil only. It can't be used for anything else. Only the main memory can be used for actual "memory allocation" for any purpose. Blocks in eDRAM are pre-allocated for a singular purpose. The only transfer capability it has is to copy its contents into main memory. You can't use the eDRAM as extra memory space at all.

Yes but if you did not had the EDram, you would need to have the same(or+ in this case), in main memory, in the end it is like it had +10 mg.

 

[Inane_Dork]

Sorry for the bump, but I had an idea.

I was thinking of shadow map generation on Xenos and how it would be sped up over the normal manner. 48 vertex shaders, 16 pixels/clock and guaranteed eDRAM bandwidth immediately came to mind. But then I thought that all the AA hardware goes to waste because an AAed shadow map doesn't have a meaning AFAIK.

But then I thought developers could specify 4x AA on the shadow map and render at 1/4 the target resolution. Then just write the whole unresolved map tile by tile out to memory. Is this possible? If so, it could be a huge boost in fillrate performance on shadow maps.

The problem, as I saw it, is the sample pattern. If the pattern is Rotated Grid, the shadows might look weird along the edges. Also, there could be any number of platform or hardware limitations I'm not aware of.

 

[Fafalada]

Also remember that Xbox 1 reserved some space for the OS too. Let's estimate that as 1 MB.

So does PS2 actually, not sure what the actual number is on XBox though. Anyway you should also expect PS3 to reserve memory for kernel just like 360 - the concept of a large kernel that also standardizes certain game functions was actually first started by PSP, and Sony's been pretty vocal about similar functionality of PS3.

 

[London Geezer]

Also remember that Xbox 1 reserved some space for the OS too. Let's estimate that as 1 MB.

So does PS2 actually, not sure what the actual number is on XBox though. Anyway you should also expect PS3 to reserve memory for kernel just like 360 - the concept of a large kernel that also standardizes certain game functions was actually first started by PSP, and Sony's been pretty vocal about similar functionality of PS3.

Standardandindirindirindize what features?

 

[Farid]

the concept of a large kernel that also standardizes certain game functions was actually first started by PSP, and Sony's been pretty vocal about similar functionality of PS3.

The memory footprint required by the OS in the PSP, as you know, as been reduced recently by Sony, for undisclosed reasons (As far as I know).

 

[Mefisutoferesu]

In what sense has it been reduced? Are we talking Sony pulled stuff from the OS or is it just optimizations? Perhaps a better questions is how did they reduce the footprint?

 

[ShootMyMonkey]

The amount of space that Xbox 1 reserved was pretty small. Less than 512k, I think. And it really didn't standardize many feature aside from virtual memory and device drivers (of which there was only one of each).

In 360's case, I also think there's a certain extent to which the footprint is pretty small except for the GUI subsystem -- the Live HUD business probably takes up the bulk of that 32 MB, which is probably something that PS3 to which won't have a parallel.

 

[Titanio]

The amount of space that Xbox 1 reserved was pretty small. Less than 512k, I think. And it really didn't standardize many feature aside from virtual memory and device drivers (of which there was only one of each).

In 360's case, I also think there's a certain extent to which the footprint is pretty small except for the GUI subsystem -- the Live HUD business probably takes up the bulk of that 32 MB, which is probably something that PS3 to which won't have a parallel.

I think Sony's PS3 OS may be pretty pervasive..I think it'll be a similarly "always-on" thing, that you can pull out any time and do different things with, or have things going on in the background, be they game related or not. Don't be surprised if they reserve a reasonable amount of resources, RAM or otherwise (think of the granularity of the SPEs), for the OS.

 

[ShootMyMonkey]

Don't be surprised if they reserve a reasonable amount of resources, RAM or otherwise (think of the granularity of the SPEs), for the OS.

I'm not saying it won't be pervasive. I'm saying PS3's OS will probably be quite different in the functionality it exposes as opposed to 360's.

I also wonder about the whole automated apulet distribution thing. Would that necessarily be an OS feature or an API feature? If it's an OS feature, then perhaps further OS reflashes would incur changes in performance of existing games, whereas if it's an API feature, it lies on the game disc and is received by the developer and not the consumer.

 

[darkblu]

The memory footprint required by the OS in the PSP, as you know, as been reduced recently by Sony, for undisclosed reasons (As far as I know).

would you elaborate?