Digital Foundry Article Technical Discussion Archive [2013]

[Xenus]

The big question at hand doesn't seem to be the allocation shifty but is the adressing unified so that you can write via the CPU buss and read from the same location using the GPU Bus later and vice versa without the need to copy or pass data along a different Bus.

 

[Silent_Buddha]

If only there was some means of cross-generation gaming. If AC4 is anything like AC:B, or AC:R then I will have to base which version I purchase based on what version my friends get if I ever want to play multiplayer. It's a bit of a shame when I think the real experience of the game is strictly the single player aspect.

I was hoping DF article would maybe have some details on that.

It'd be a bit surprising if there wasn't cross generational play at least between X360 and Xbox One as there isn't going to be a reboot of Xbox Live with regards to multiplayer as there was for the X360.

I haven't heard about Sony changing things much for PSN either, so I'm assuming it should be possible for PS3/PS4 as well.

Regards,
SB

 

[ERP]

It'd be a bit surprising if there wasn't cross generational play at least between X360 and Xbox One as there isn't going to be a reboot of Xbox Live with regards to multiplayer as there was for the X360.

I haven't heard about Sony changing things much for PSN either, so I'm assuming it should be possible for PS3/PS4 as well.

Regards,
SB

The issue isn't just the infrastructure, a lot of it is testing, it's easier for a developer to just not allow it and then not have to test it.
The way most multiplayer works, it really shouldn't be an issue, but there are always bizarre things that turn up.

 

[patsu]

So what are the real advantages of unified memory if the processors still have to be treated as if accessing two different memory pools? I had always thought they'd have arbitrary random access to all game memory locations.

Unified memory allows the devs to allocate memory in a more flexible way (not restricted by h/w separation).

It appears that the access is not so uniform. One is optimized for GPU use, the other for CPU. Bandwidth is dedicated for different uses. Reminds me of NUMA architecture.

 

[gurgi]

I want to remember the GGDR5 was supposedly accessible without the burst speed of the GGDR5 at lower latencies. Tagging the memory via the different busses might be how this is achieved?...or perhaps that is a different flag.

 

[HokutoNoKen]

PlayStation 4 gives up to 5.5GB of RAM to game developers

http://www.eurogamer.net/articles/digitalfoundry-ps3-system-software-memory

/ Ken

 

[warb]

4.5GB guaranteed, 1GB "flexible memory" may be reclaimed from the OS based on availability.

So the OS and app reserve is even bigger than on Xbox One. I wonder why that's necessary.

 

[joker454]

PlayStation 4 gives up to 5.5GB of RAM to game developers

http://www.eurogamer.net/articles/digitalfoundry-ps3-system-software-memory

/ Ken

Makes sense, they can afford to do that given the xb1's memory setup hence better to be safe than sorry. After all the last thing they want is another cross game chat type scenario, so just go parity for now and reduce as needed later. In any case the gpu's in the new machines are relatively weak, I always wondered if they were even capable of rendering ~8gb worth of visual data per frame on a typical modern game.

 

[Shifty Geezer]

If you have the BW, 8GBs of assets is as straightforward to use as 4 GBs repeated. It means no repeated building objects versus every other house in the next Elder Scrolls game being a clone. I won't argue that 8 GBs is a LOT of game and devs may be hard pushed to use it, but 3 GBs is far, far more for an OS that isn't a full-fledged PC running multitasked applications. I'd rather have 2 GBs of disk cache (virtual textures and meshes) and smoother games.

 

[joker454]

If you have the BW, 8GBs of assets is as straightforward to use as 4 GBs repeated. It means no repeated building objects versus every other house in the next Elder Scrolls game being a clone.

It's usually more than just bandwidth, more visual assets will affect efficiency of instancing, gpu state changes, cache, alu use and so on. Eventually you hit a wall of what the gpu can effectively use for pure visual benefit.

I won't argue that 8 GBs is a LOT of game and devs may be hard pushed to use it, but 3 GBs is far, far more for an OS that isn't a full-fledged PC running multitasked applications. I'd rather have 2 GBs of disk cache (virtual textures and meshes) and smoother games.

It's hard to say of 3gb is a lot without knowing what they have planned for it going a few years out.

 

[Nesh]

I must say that I am now even more disappointed with next gen now
Just when we felt that developers were delighted to have more memory under their disposal now we hear that Sony has also reserved 3GB for OS

 

[BRiT]

Technically it's a larger or smaller range not usable by the game -- 3.5 - 2.5 GB non-game usage.

 

[DrJay24]

I must say that I am now even more disappointed with next gen now
Just when we felt that developers were delighted to have more memory under their disposal now we hear that Sony has also reserved 3GB for OS

Originaly the PS4 was targeting 2GB then 4GB total according to rumors. They are not taking memory from dev (who never had it), they are adding to other features and apps.

 

[orangpelupa]

at least this means "bye-bye" to horrible super slow PS3 XMB.
PS4 should have very fast and consistent speed on the whole PS4 XMB experience with that much ram.

 

[eastmen]

I must say that I am now even more disappointed with next gen now
Just when we felt that developers were delighted to have more memory under their disposal now we hear that Sony has also reserved 3GB for OS

This could just be a short gen.


ps360 gen is way past its welcome with even mobile hardware now putting out similar graphics. in year 9 and 10 of the generation it will only get worse.

Perhaps ps4/one will last just 4 or 5 years. Think about it. 5 years from now we get xbox two and ps5 . Both fully BC and both using next gen AMD mobile chips with even larger gpus and stacked ram with ssd drives.


I wouldn't mind $500 every 5 years. This gen was way to long

 

[Rangers]

I must say that I am now even more disappointed with next gen now
Just when we felt that developers were delighted to have more memory under their disposal now we hear that Sony has also reserved 3GB for OS

So, 460-480 MB to 5GB isn't a big increase?

These devs wont even know what to do with all the space.

 

[dagamer]

So, 460-480 MB to 5GB isn't a big increase?

These devs wont even know what to do with all the space.

Not only that, most launch games are cross-gen.

This could just be a short gen.


ps360 gen is way past its welcome with even mobile hardware now putting out similar graphics. in year 9 and 10 of the generation it will only get worse.

Perhaps ps4/one will last just 4 or 5 years. Think about it. 5 years from now we get xbox two and ps5 . Both fully BC and both using next gen AMD mobile chips with even larger gpus and stacked ram with ssd drives.


I wouldn't mind $500 every 5 years. This gen was way to long

I really hope we're not spending $500 on a box that only lasts 5 years. Previous generations had pretty aggressive reductions in price after 2-3 years, whereas the 360 has honestly only had one price cut ($100) and the PS3 still hasn't had a single SKU below $249. It's going to take forever to get a decent install base at these prices.

 

[eastmen]

Why ?

xbox = large die Plus lots of cheap ram = micron drops will cause large drops in price.


ps4 = large die plus lots of expensive ram = micron drops will cause large drops in price.


I can see within 2-3 years both consoles being under $300 and by year 5 both being under $200. These are far less complex to build than last gen.

I rather short gens of 5 years to keep tech fresh. mobile is upgraded twice a year , they will catch up to current systems quicker than 8 years this time

 

[Silent_Buddha]

As some of us speculated before it only makes sense for Sony to have a similar memory split in the PS4 as the Xbox One. Cross platform games would have been unlikely to take advantage of more. And for first part developers it's unlikely that launch or first year titles would be able to visually benefit from more.

Later in the generation as Sony is more certain of what they want out of the OS, you can always then free up more memory. You can't do the opposite if you suddenly realize that you didn't reserve enough for the OS.

What seems weird is the variably nature of the game memory. 4.5 GB with a flexible 1 GB if available. Will this actually get used if it can't be guaranteed to be available for the game? Variable asset quality depending on how much memory the OS makes available/unavailable to the game?

And if that 1 GB truly is flexible meaning that it isn't always available to for games (in part or in whole) that means Sony must already have something that is potentially causing the OS to use ~3.5 GB of memory. Otherwise they could just guarantee that games have 5 or 5.5 GBs of memory in the first place. That they can't means that it's getting used at some point.

I'm really curious to see what they are doing with this as Sony hasn't really shown much with regards to their plans for the OS and non-gaming side of the equation. Perhaps Sony actually will present something non-gaming oriented that I will find compelling after all.

Quick thought maybe it's 5.5 GB for games unless the PS4 camera and Move are connected in which case it potentially drops to only 4.5 GB available? Perhaps more than 4.5 but less than 5.5 if only Move is connected or only camera is connected?

Regards,
SB

 

[chris1515]

As some of us speculated before it only makes sense for Sony to have a similar memory split in the PS4 as the Xbox One. Cross platform games would have been unlikely to take advantage of more. And for first part developers it's unlikely that launch or first year titles would be able to visually benefit from more.

Later in the generation as Sony is more certain of what they want out of the OS, you can always then free up more memory. You can't do the opposite if you suddenly realize that you didn't reserve enough for the OS.

What seems weird is the variably nature of the game memory. 4.5 GB with a flexible 1 GB if available. Will this actually get used if it can't be guaranteed to be available for the game? Variable asset quality depending on how much memory the OS makes available/unavailable to the game?

And if that 1 GB truly is flexible meaning that it isn't always available to for games (in part or in whole) that means Sony must already have something that is potentially causing the OS to use ~3.5 GB of memory. Otherwise they could just guarantee that games have 5 or 5.5 GBs of memory in the first place. That they can't means that it's getting used at some point.

I'm really curious to see what they are doing with this as Sony hasn't really shown much with regards to their plans for the OS and non-gaming side of the equation. Perhaps Sony actually will present something non-gaming oriented that I will find compelling after all.

Quick thought maybe it's 5.5 GB for games unless the PS4 camera and Move are connected in which case it potentially drops to only 4.5 GB available? Perhaps more than 4.5 but less than 5.5 if only Move is connected or only camera is connected?

Regards,
SB

Like, I said in the other topic, Some gaming stuff in the reserved RAM( Gakai, Remote play, progressive download and streaming, share...).

I don't like the article because it gives no details...