Xbox One (Durango) Technical hardware investigation

[Betanumerical]

Devs have said for a while now that flops aren't important really. And given the display planes I doubt the ROPs difference, whatever it is in actual games, is going to matter. The bandwidth the GPU sees isn't remarkably different either. So I'm not really sure I'd trust the internet on this, since this consensus you talk of is really just ppl comparing numbers on metrics that either aren't all that tangibly related to game visuals or they are in areas with highly diminished returns as is.

The ROP difference I am lead to believe is 100% is it not?, so the PS4 GPU has 2x the fill of the Durango GPU, I do not think that these display planes will make up for anywhere near something like that. Even if they do magically add somewhere near 100% more effiency to the fillrate, the PS4 has something that is nearly identical, the only difference is it has 2 not 3.

Even if we assume that it has 0 display planes, we have already computed that it would only take 1CU to do the entire Durango display functionality at 1080P 60FPs.

What people use the fill for, and if it actually has any large benefit is entirely a different question, although I have a feeling that Sony didn't go with this number for no reason and they must seen a benefit for it.

 

[Cjail]

There's only about 2GB reserved for the OS, about 1GB is reserved but currently unused, MS can release the memory to devs (unlikely) if they wish, they're keeping it for future OS expansion and features.

May I dare to ask your personal opinion on this choice?

 

[Bagel seed]

My guess on this delay of announcement is solely due to getting OS features up to snuff. MS wants to wow people with a snazzy UI and multitasking abilities. Previously rumors put it at close to 3gb so if it's 2 now with 1 still reserved it's probably for functionality that couldn't be locked in time for unveiling.

 

[Esrever]

My guess on this delay of announcement is solely due to getting OS features up to snuff. MS wants to wow people with a snazzy UI and multitasking abilities. Previously rumors put it at close to 3gb so if it's 2 now with 1 still reserved it's probably for functionality that couldn't be locked in time for unveiling.

my guess is they want the playstation hype to die down enough before bringing everything and just have 1 push into e3 and toward release. Sony really gained nothing to announcing early. Especially with rumor of no BC.

 

[Bagel seed]

One rumored feature that I'm interested in is the ability to switch between playing 2 games. Sometimes I feel like playing a light arcadish game and other times something more significant. My worsening ADD keeps me from staying focused on long playing sessions of a single game... being able to keep two games loaded up to quickly switch between is pretty convenient.

 

[dagamer]

One rumored feature that I'm interested in is the ability to switch between playing 2 games. Sometimes I feel like playing a light arcadish game and other times something more significant. My worsening ADD keeps me from staying focused on long playing sessions of a single game... being able to keep two games loaded up to quickly switch between is pretty convenient.

That rumor doesn't make any sense, there's no arbitrary difference between a "full" game and a "light arcade" game in terms of the amount of RAM available to developers. If a game has access to 5GB of RAM and another game gets started, its content will be booted.

I do like keeping 1GB of RAM for "future proofing", especially when we have no idea how long this system will be around.

 

[(((interference)))]

No, you should be able to play Win8 games (like Win8 apps) simultaneously with full Durango games. Win 8 apps run on the 2GB reserved memory.

May I dare to ask your personal opinion on this choice?

I thought 5GB is enough when you have only DDR3, but now PS4 is 8GB GDDR5 I'm not so sure whether it'll be an issue for them as time goes on.

Devs definitely don't like it though, they were apparently quite vocal about having access to only a 5GB, 6 core machine

 

[(((interference)))]

Previously rumors put it at close to 3gb so if it's 2 now with 1 still reserved it's probably for functionality that couldn't be locked in time for unveiling.

No, it was always 2+1 reserved the rumours just didn't make a distinction between reserved and currently being used by the OS, and reserved for future use

 

[Bagel seed]

That rumor doesn't make any sense, there's no arbitrary difference between a "full" game and a "light arcade" game in terms of the amount of RAM available to developers. If a game has access to 5GB of RAM and another game gets started, its content will be booted.

I know, I was just giving an example. Any two games would be available to be loaded up if what was said in the tech docs is to be believed, unless..

No, you should be able to play Win8 games (like Win8 apps) simultaneously with full Durango games. Win 8 apps run on the 2GB reserved memory.

So one full Durango game plus Win8 game only? No 2 full Durango games then? Guess it makes sense. Though it might be a bit cumbersome they could implement some kind of state saving for games, write to HDD and swap back into mem to load it back up on demand.

 

[(((interference)))]

I'm not sure how they'll do it exactly, Durango games run in VMs (B3D rumour exclusive ) so that offers a lot more versatility in backgrounding and suspend/resume etc.

Games only 'see' a 5GB/6 core machine, using VMs makes resource sharing with the OS much easier - eg when Durango games background the system can fold two of their 6 cores onto their other 4 physical ones, and devs don't have to do anything special with thread affinity etc.

 

[Bagel seed]

The full quote from Kotaku on game juggling

The Durango will be able to run more than one game or app at once, according to the information shared with us. If you're, say, a computer or smartphone user, this is not exactly sending-a-man-to-the-moon level of innovation. But game consoles have long been stuck just running the system-level functions (cross-game voice-chat, Achievement alerts, etc) while a single game runs. On an Xbox 360, even an app as simple as Twitter could only be used if whatever game the user was playing was shut down first. Durango, thankfully, gets past that.

The Durango is said to also allow games to be put into "suspend" and "constrained" states, which seemingly allow users to pause a game, switch to a second game, then return to the first game without losing their place, provided game developers follow some Microsoft protocols. Again, this is no revolution for users of computers, phones, or even Nintendo and Sony handheld gaming machines, but it is one giant leap for consoles.

There's the state saving that I meant.

I'm not sure how they'll do it exactly, Durango games run in VMs (B3D rumour exclusive ) so that offers a lot more versatility in backgrounding and suspend/resume etc.

Games only 'see' a 5GB/6 core machine, using VMs makes resource sharing with the OS much easier - eg when Durango games background the system can fold two of their 6 cores onto their other 4 physical ones, and devs don't have to do anything special with thread affinity etc.

Interesting. For the new page

 

[dagamer]

Do we have any idea what those 2 other cores will be used for? It sounds like Sony instead built a separate "OS" chip to handle background tasks instead of taking away resources from the main CPU. But then I wonder how you can use only 2 cores of a CPU without needing active cooling for when the system is in "standby"

 

[Gradthrawn]

Do we have any idea what those 2 other cores will be used for? It sounds like Sony instead built a separate "OS" chip to handle background tasks instead of taking away resources from the main CPU. But then I wonder how you can use only 2 cores of a CPU without needing active cooling for when the system is in "standby"

A distinction needs to be made between the Southbridge Custom Chip being used for background task, and the active front-end OS. All we have confirmation on is that the Custom Chip will be used for background tasks whether the system is active or in a suspended state. That does not imply that it will be used for "in-game" OS tasks (bringing up the CUX, checking messages, etc). We know there's a memory reservation. But reserved CPU resources have not been made public or even clearly defined in rumors yet. The DF article clearly implies less reserved resources for the OS across the board than Durango, but no clear number (outside of memory).

As for the Durango, I don't think we have any confirmation that it won't have a similar solution for background tasks as well. They're probably targeting the same low power standby modes that Sony is for various regional compliance. In other words, its quite possible both systems have reserved CPU resources for the OS, along with low power chips to handle tasks while in a standby or low power state.

 

[(((interference)))]

The full quote from Kotaku on game juggling

The Durango will be able to run more than one game or app at once, according to the information shared with us. If you're, say, a computer or smartphone user, this is not exactly sending-a-man-to-the-moon level of innovation. But game consoles have long been stuck just running the system-level functions (cross-game voice-chat, Achievement alerts, etc) while a single game runs. On an Xbox 360, even an app as simple as Twitter could only be used if whatever game the user was playing was shut down first. Durango, thankfully, gets past that.

The Durango is said to also allow games to be put into "suspend" and "constrained" states, which seemingly allow users to pause a game, switch to a second game, then return to the first game without losing their place, provided game developers follow some Microsoft protocols. Again, this is no revolution for users of computers, phones, or even Nintendo and Sony handheld gaming machines, but it is one giant leap for consoles.

There's the state saving that I meant.

See, with VMs that's all very trivial to do, you just suspend/resume the VM for each game.

In fact, games are also going to be shipped/downloaded as encrypted VMs, Durango just loads the VM into memory to play.

 

[Gradthrawn]

In fact, games are also going to be shipped/downloaded as encrypted VMs, Durango just loads the VM into memory to play.

That's bad-ass, and I suspect a step above what Sony has planned for its suspend/resume function (they only mentioned this for suspending/resuming the console, nothing about doing so in an active state and launching a new app). Now, let me import those VMs into my ESXi hosts, sorry, I mean my Hyper-V hosts, and build a whole home Durango server. Why? Because is why.

 

[Bagel seed]

Yep that is definitely a cool feature. I suppose there wouldn't really be a limit on the number of suspended games either. Reminds me of Snes emulators and jumping right back into where I left off. Though I remember I abused that feature quite a bit using multiple save states to cheese my way through tough parts in a game, lol.

 

[Trawler]

In fact, games are also going to be shipped/downloaded as encrypted VMs, Durango just loads the VM into memory to play.

Won't that mean the entire download will need to complete before the user can play? This is in contract to what we've heard about games starting straight away when played off optical media (or was that PS4? getting my rumors confused).

 

[AzBat]

Won't that mean the entire download will need to complete before the user can play? This is in contract to what we've heard about games starting straight away when played off optical media (or was that PS4? getting my rumors confused).

Look into Numecent's Cloudpaging technology. Numecent spinned off the technology for gaming use to another company called Approxy. They demonstrated deploying a 66gb Microsoft's Hyper-V virtual machine by only cloudpaging 900mb.

http://www.numecent.com/
http://approxy.com/
https://www.google.com/search?q=Numecent Approxy Cloudpaging

Maybe Microsoft has either come up with their own technology or licensing theirs?

Tommy McClain

 

[dagamer]

A distinction needs to be made between the Southbridge Custom Chip being used for background task, and the active front-end OS. All we have confirmation on is that the Custom Chip will be used for background tasks whether the system is active or in a suspended state. That does not imply that it will be used for "in-game" OS tasks (bringing up the CUX, checking messages, etc). We know there's a memory reservation. But reserved CPU resources have not been made public or even clearly defined in rumors yet. The DF article clearly implies less reserved resources for the OS across the board than Durango, but no clear number (outside of memory).

As for the Durango, I don't think we have any confirmation that it won't have a similar solution for background tasks as well. They're probably targeting the same low power standby modes that Sony is for various regional compliance. In other words, its quite possible both systems have reserved CPU resources for the OS, along with low power chips to handle tasks while in a standby or low power state.

Ah that's true. I shouldn't mix the two.

Supposedly it's less than one core reserved by the OS for PS4.

Interesting. This brings up an important point. I think the philosophy of a console is far more important than what's on some spec sheet (though the spec sheet reveals quite a bit). Sony throwing better hardware in their system indicates they want to make a real powerhouse and focus 70/30 on games. Microsoft instead reserving 2GB of RAM for OS functions and even an extra 1GB of wiggle room means they literally see this as a "living room PC" which more closer lines up to the original idea of the first Xbox in it's conceptual stages in the late 90s.

 

[(((interference)))]

That's bad-ass, and I suspect a step above what Sony has planned for its suspend/resume function (they only mentioned this for suspending/resuming the console, nothing about doing so in an active state and launching a new app). Now, let me import those VMs into my ESXi hosts, sorry, I mean my Hyper-V hosts, and build a whole home Durango server. Why? Because is why.

Yes, it is interesting - this also has some disadvantages though, it's why we're hearing the PS4 is more 'open' to devs - they don't have any direct access to hardware on Durango, it all goes through the hypervisor (which manages the title and system VMs, communication between the two and all hardware access)

It shouldn't be too big of an issue though, they have Dave Cutler, (who was in charge of optimising VM performance for Azure) working on low overhead virtual drivers for Durango. That's what his new job in Xbox division is:
http://www.zdnet.com/blog/microsoft...ather-of-windows-nt-now-working-on-xbox/11684

Won't that mean the entire download will need to complete before the user can play? This is in contract to what we've heard about games starting straight away when played off optical media (or was that PS4? getting my rumors confused).

I don't know how they're going to manage playing partial downloads with VMs, I'm pretty sure they'll have that feature though (ie if the rumours have mentioned that the 720 will do this, like PS4, then I certainly haven't heard anything contrary)