The next generation wars are heating up. Microsoft’s done the announcement of an announcement thing, letting us know that they’ll be ready to show the world the next Xbox on May 21. We’ve heard a fair deal about Sony’s PlayStation 4 as well, including details of its architecture. Speaking to Gamasutra, Sony’s PlayStation4 lead architect, Mark Cerny, has gone in to a little more depth about the design choices that were made in designing the system’s innards, which they’re calling “Supercharged PC architecture”
What the heck do they mean by supercharged? Well, it’s all a little technical and complicated – but Cerny and Sony’s other hardware engineers have spent long hours trying to come up with a system that isn’t held back by the sort of bottlenecks you get on PCs.
"A typical PC GPU has two buses," said Cerny. "There’s a bus the GPU uses to access VRAM, and there is a second bus that goes over the PCI Express that the GPU uses to access system memory. But whichever bus is used, the internal caches of the GPU become a significant barrier to CPU/GPU communication — any time the GPU wants to read information the CPU wrote, or the GPU wants to write information so that the CPU can see it, time-consuming flushes of the GPU internal caches are required.”
So how does one get around that sort of thing? According to Cerny, they’ve made three fundamental changes to the architecture, to make it more efficient.
- "First, we added another bus to the GPU that allows it to read directly from system memory or write directly to system memory, bypassing its own L1 and L2 caches. As a result, if the data that’s being passed back and forth between CPU and GPU is small, you don’t have issues with synchronization between them anymore. And by small, I just mean small in next-gen terms. We can pass almost 20 gigabytes a second down that bus. That’s not very small in today’s terms — it’s larger than the PCIe on most PCs!
- "Next, to support the case where you want to use the GPU L2 cache simultaneously for both graphics processing and asynchronous compute, we have added a bit in the tags of the cache lines, we call it the ‘volatile’ bit. You can then selectively mark all accesses by compute as ‘volatile,’ and when it’s time for compute to read from system memory, it can invalidate, selectively, the lines it uses in the L2. When it comes time to write back the results, it can write back selectively the lines that it uses. This innovation allows compute to use the GPU L2 cache and perform the required operations without significantly impacting the graphics operations going on at the same time — in other words, it radically reduces the overhead of running compute and graphics together on the GPU."
- Thirdly, said Cerny, "The original AMD GCN architecture allowed for one source of graphics commands, and two sources of compute commands. For PS4, we’ve worked with AMD to increase the limit to 64 sources of compute commands — the idea is if you have some asynchronous compute you want to perform, you put commands in one of these 64 queues, and then there are multiple levels of arbitration in the hardware to determine what runs, how it runs, and when it runs, alongside the graphics that’s in the system."
If you’re not particularly technically minded (like Darryn), your eyes have quite likely glazed over by now. If you are though, you can quite plainly see that Sony’s hardware architects have put a heck of a lot of thought (of the forward-thinking variety) in to the system, and have learned from their past mistakes. The PS4 is going to be a beast, utilising a custom designed, more efficient take on existing PC hardware that should be an absolute dream for game developers.
There’s a lot more to it in Gamasutra’s 3-page in-depth look at what the PS4 offers– and it’s well worth a look if you’re even remotely interested in the PS4’s hardware.
Last Updated: April 25, 2013
Anon A Mouse
April 25, 2013 at 12:05
Geoff no disrespect for your write up but since I only know where to switch on a laptop I think you should have had Darryn do this one, at least then I’ll feel smarter than a 5th grader.
Admiral Chief Erwin
April 25, 2013 at 12:07
VIVA for better games, VIVA!!!
OldVideoGamer
April 25, 2013 at 12:08
2 BUSES? how do they fit inside?
Anon A Mouse
April 25, 2013 at 12:12
And how do you know when to press L1 or L2 for the information to caches the correct bus. What about unprotected strikes for more cash? What if one of the buses are burned to the ground? This doesn’t sound very forward thinking as Geoff suggests.
OldVideoGamer
April 25, 2013 at 12:16
caches the correct bus to BLU-RAY lane where all the drunks are bottle necking for a drive to get away from the pirates docked at the usb port.
need more coffee
Skoobaz
April 25, 2013 at 13:58
Quicktime events of course!
ZombieHunta
April 25, 2013 at 16:46
Quicktime? But then they’ll need to license it from Apple. Why not VLC?
Skoobaz
April 25, 2013 at 16:52
VLC events? hmm. Doesn’t have the same bad experience association with it.
umar bastra
April 25, 2013 at 12:30
“What is this??? A Centre for Ants ????
I DON’T WANA HEAR YOUR EXCUSES!!
The Centre has to be at least ….. 3 times the size of this!”
Thanx man for the biggest laugh of the day
umar bastra
April 25, 2013 at 12:30
“What is this??? A Centre for Ants ????
I DON’T WANA HEAR YOUR EXCUSES!!
The Centre has to be at least ….. 3 times the size of this!”
Thanx man for the biggest laugh of the day
Sageville
April 25, 2013 at 14:10
Thanks for that, me snorting coffee on my laptop earns you an upvote.
OldVideoGamer
April 25, 2013 at 12:12
and tax payer
Sir Rants-a-Lot Llew
April 25, 2013 at 12:23
Now you see, this is the kind of thing I like. Instead of saying nonsense like “it’s more powerful than any PC because it has 8GB of RAM” (who was that guy again?) and instead showing this is much MUCH better. Now we can see how it’s going to perform better than PC’s with the same specs and even higher.
Finally! Someone backed up claims with some proper technical facts!
Although I do have one gripe “That’s not very small in today’s terms — it’s larger than the PCIe on most PCs!”
This statement is very quickly becoming redundant as most PC’s are coming out with PCIe3.0 nowadays and PCIe3.0 can handle up to 32GB/s (Granted it’s theoretical and I think it’s currently at 15GB/s)
But I digress. Some very impressive stats and if it can do 20GB/s AND bypass L1 and L2 cache then this is going to be a beast.
Sir Rants-a-Lot Llew
April 25, 2013 at 12:40
Small correction, PCIe is actually currently sitting at 32GB/s in a 16lane configuration (so 1xGFX card running on a 16X PCIe3.0 can achieve 32GB/s transfer rate aggregated between up and down)
Admiral Chief Erwin
April 25, 2013 at 12:49
LC FTW
Joe Brown Pha
April 25, 2013 at 14:11
This is not to be rude, but I think your missing the point…even tho campared to a PC (rightfully so)….the big hype about the PS4 is this is a LEAP forward not viewed to be possible in a console (at least not for longer than believed, as well as a huge leap beyond that of ANY previous console’s concept)…so yes for the PS4 to be a CONSOLE and be compared to half of a super gaming computer…then YES THATS HUGE…for console and PC gamers alike everyone finally has a better smoother taste of gaming similar to that of a PC (which we all know has a huge advantage “tech wise” over consoles)…but now with the PS4 that gap isnt so big anymore and now PC gamers as well as developers who refused to game on consoles can finally now start enjoying a consoled gaming experience almost as much as a pc gaming experience….I believe thats the ultimate point trying to be made
Sir Rants-a-Lot Llew
April 25, 2013 at 14:18
No I picked up on that. Simply pointing out where they tend to make comparison mistakes. That’s all.
The PS4 looks to be an amazing piece of hardware and is an absolutely huge leap forward.
What I don’t get is why people are trying to compare them to the power of PC’s. It’s a stupid to do so because once it releases everyone’s going to say “Oh look, it still can’t compete with the power of a PC even though they promised it would beat even the top end PC’s now”
That’s going to damage the reputation of an otherwise great piece of hardware. It generates false views of what it can or can’t do and the gaming community has already shown how nitpicky they can be and tear to shreds anything that doesn’t live up 100% to what people said it would. That’s all.
Willem Swanepoel
April 25, 2013 at 16:58
I was laughing at all the idiots who told me the PS4 will be faster because of 8GB ram and it i was DDR5.
At least this guy is not talking bs through his ass. The others need some bleaching …
Trebzz
April 25, 2013 at 12:26
Oh no cue the angry PC people
Sir Rants-a-Lot Llew
April 25, 2013 at 12:34
Not at all. This is good news for everyone. And if they can back up claims with actual proper information like this then great.
It’s when they tune nonsense like “It’s the most powerful PC because it has 8GB of ram” that make people angry. Not just PC people but console people as well because it makes them all look silly and like they have no clue how tech works.
Now the above is very technical and explains exactly why and how it’s going to outperform a pc. No pc can do what is mentioned above.
Willem Swanepoel
April 25, 2013 at 17:04
Why would the PC lovers be angry? We are so fucking happy, now we can actually get some proper quality good looking games even if they are ported 😉
I wish the PS4 was like 5 years ahead in technology than current PC so that we can enjoy this good news even longer 😉
Ultimo_Cleric_N7
April 25, 2013 at 12:29
Silly Geoff, there have already been graphical coparisons and the PC wins by a mile.
Sir Rants-a-Lot Llew
April 25, 2013 at 12:31
!@#$ the buss strike!
Admiral Chief Erwin
April 25, 2013 at 12:46
You should rename your nick to Sir WALKS-a-Lot-Llew
Sir Rants-a-Lot Llew
April 25, 2013 at 12:47
*le sigh*
Admiral Chief Erwin
April 25, 2013 at 12:49
Speaking of, where is the old bugger today?
Sir Rants-a-Lot Llew
April 25, 2013 at 12:50
Good question? Mmmm. Very odd
Martin du preez
April 25, 2013 at 12:32
Thank you Sony and thank you Kaz.
Necro
April 25, 2013 at 12:38
Yeah,e xcept by the time new consoles launch we’ll have the next generation of graphics cards on CPUs for PC, at which point the PS4 hardware would be 1.5-2 years old and completely irrelevant.
Fnuik
April 25, 2013 at 13:17
And every pc user will have to upgrade to said new graphics cards and CPU’s in order to play newest games and the PS4 crowd will be happily playing ANY game available to them without worrying about specs…
Sir Rants-a-Lot Llew
April 25, 2013 at 13:32
All users will have to upgrade to the new PS4 to be able to play said games
Fnuik
April 25, 2013 at 13:35
True, but before the PS5 is launched the pc crowd will have to upgrade once or twice again. Not arguing that one is better than the other, was just trying to make a point that Necro’s comment about ps4 being irrelevant in 2 years was a bit of a bs comment.
Willem Swanepoel
April 25, 2013 at 17:02
yeah true, because after all the PS4 games purchases you would have spent more money on games where I could have saved my money for 2-3 PC upgrades 10 years later.
No point arguing. You pick your shit what you like and I pick mine. No point to say my dick is bigger … on the end of the day we both will have our entertainment.
Chris Wood
April 25, 2013 at 20:32
Right, that’s probably true, but when the PS5 is launched the Playstation Crowd will have spent about $600-700 more on games because they will cost between $20-30 more on console. So we have cutting edge graphics, all the other amazing benefits of PC gaming, and it’s cheaper in the long run too. Who would have thought?!
If you want to see the benefits of PC gaming that aren’t just “better graphics hurr durr” then look here:
http://tngsystems.co.uk/#/why-pc-gaming/4574067414
Chris Wood
April 25, 2013 at 20:30
Lol shut the fuck up clueless clarence. I’ll happily be playing the games on my DX11 2009 5850 and my 2009 i5 750.
As long as your GPU supports DX11 and has good power you will happily be able to play the latest games. It’s retards like you who think that just because a new GPU comes out we have to upgrade. I have the Iphone 4. OH SHIT ME THE 4S AND 5 HAVE COME OUT?!?!?! ITS ANY WONDER HOW THIS NOW OBSOLETE USELESS CRAP PHONE STILL WORKS WHEN THERE ARE TWO WHOLE MORE NEWER MODELS OF PHONES OUT!
Please, get educated. Spastic.
Fnuik
April 25, 2013 at 20:42
Chill out dude. My comment was aimed at necros remark that the ps4 will be irrelevant when newer pc hardware is released. If your old pc can still make it irrelevant then good for you. Heaven forbid someone says anything not to your liking. I almost deleted the internet from my phone/laptop in fear of saying something that might kill you.
Slagywag
April 25, 2013 at 13:10
The PC preview of Unreal Engine 4 is still miles better than the PS4… Take a look at the side by side and notice how much they skipped out on
matthurstrsa
April 25, 2013 at 13:30
Your move, Microsoft.
Microsoft
April 25, 2013 at 14:51
PIZZA!!!!!
Sir Rants-a-Lot Llew
April 25, 2013 at 14:58
ROFL ROFL ROFL ROFL ROFL
Tateboetie Malaaitie
April 25, 2013 at 13:56
How a ps4 is going to be better than a pc.
Tateboetie Malaaitie
April 25, 2013 at 13:57
I accidentally better than pc.
Johan du Preez
April 25, 2013 at 14:04
LOL
Nice try ….
PC with a 660ti in will still have more memory bandwidth than the ps4 and thus faster the PCI 16x slot puts out 32gbps for the average motherboard these days. Its nice to confuse non technical people but they just admitted and showed that it will be slower than a PC.
Karel Venter
April 25, 2013 at 14:37
Anyone still trying to compare to PCIe3.0 or PC architecture in general READ GAMASUTRA IN-DEPTH ARTICLE.
“..a 256-bit bus…communicates with the shared pool of ram at 176 GB per second.”
Derpentine
May 8, 2013 at 08:07
Obviously not the same thing. That is GPU to RAM bandwidth. On a PC, the graphics cards have their own, dedicated RAM. For example the Radeon HD 7950 has 240 GB/s bandwidth to its RAM. Then the CPU has its own RAM and bandwidth too. An Intel 2600k at stock speeds with DDR3 2166 at average timings has 26.8 GB/s bandwidth. PCIe is a TOTALLY different metric and has absolutely no relevance to the number you have posted. http://www.tweaktown.com/articles/4416/intel_x79_quad_channel_and_z68_dual_channel_memory_performance_analysis/index5.html
Kevin A-Z
April 25, 2013 at 14:54
I don’t think its right to compare a gaming console with a PC. I don’t think I would ever write a paper or do research on a PS4. Who know, maybe the PS4 will have the ability to do that. i think gaming consoles should stay gaming consoles, and PCs to stay PCs.
Jack
April 26, 2013 at 02:54
Unless the xbox has a similar build, the full potential of the ps4 can only be actualized with games exclusive to the PS4.
Ocelotty1
April 26, 2013 at 03:23
Extra Buses; So it’s Speedy then. 🙂
Derpentine
May 8, 2013 at 08:27
GK110 aka GTX Titan already has 32 work queues and you can buy one today (see nVidia GK110 whitepaper) giving an average desktop/server quad-core 8 queues per core. PS4 doubles both CPU cores and work queues giving an identical 8 work queues per core