JonathanPower
Member
Jaguar cores are different from Piledriver cores though.
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AMD: PlayStation 4 supports hUMA, Xbox One does not
- Thread starter ElTorro
- Start date
Jaguar cores are different from Piledriver cores though.
the XONE is not hUMA, because is UMA, and being UMA, is not necesary a 'downgrade' to be hUMA.
hUMA is a patch for UMA, that allows two or more memory busses to share a single memory pool and allow cache-coherency between the Proccesing units attached to that busses.
In this case, que GPU and the CPU of PS4 uses the Onion & Garlic busses. Onion for CPU, and Garlic for GPU. Onion has a MMU but Garlic lacks one. Onion/CPU can implement VIRTUAL MEMORY POOL, but Garlic/GPU only sees PHYSICAL ADDRESS/MEMORY POOL. this way, PS4 can use PRT, but only with PHYSICAL LOADED TEXTURES IN RAM. if the PRT engine need to 'swap' or to load new textures, needs to do by SOFTWARE.
the XONE is UMA, and access to DDR3 pool is controled by the CPU MMU. the MMU uses the ESRAM as a L3 cache for GPU memory access. this way, the GPU can view the VIRTUAL SPACE ADDRESSES offered by the MMU, and can issue directly 'page faults' from the PRT engines, allowing to create and texture worlds 'bigger than RAM'. the page fault from the GPU access is caught in the MMU, dispatched by the CPU, and requested via DMA or DME to the disk (virtual memory subsystem).
hUMA is a patch for UMA, that allows two or more memory busses to share a single memory pool and allow cache-coherency between the Proccesing units attached to that busses.
In this case, que GPU and the CPU of PS4 uses the Onion & Garlic busses. Onion for CPU, and Garlic for GPU. Onion has a MMU but Garlic lacks one. Onion/CPU can implement VIRTUAL MEMORY POOL, but Garlic/GPU only sees PHYSICAL ADDRESS/MEMORY POOL. this way, PS4 can use PRT, but only with PHYSICAL LOADED TEXTURES IN RAM. if the PRT engine need to 'swap' or to load new textures, needs to do by SOFTWARE.
the XONE is UMA, and access to DDR3 pool is controled by the CPU MMU. the MMU uses the ESRAM as a L3 cache for GPU memory access. this way, the GPU can view the VIRTUAL SPACE ADDRESSES offered by the MMU, and can issue directly 'page faults' from the PRT engines, allowing to create and texture worlds 'bigger than RAM'. the page fault from the GPU access is caught in the MMU, dispatched by the CPU, and requested via DMA or DME to the disk (virtual memory subsystem).
blastprocessor
The Amiga Brotherhood
Not nearly identical IMHO,
(PS4 in brackets)
1.2 TFLOPS (1.84 TFLOPS)
68 GB/s memory bandwidth (176 GB/s)
12 CUs (18 CUs)
16 ROPS (32 ROPS)
64 Stencil ROP Units (128 SROPS)
According to heise.de they are also targetting for 60fps with Killzone...http://www.heise.de/newsticker/meldung/Gamescom-Erste-Eindruecke-von-der-Playstation-4-1940079.html
Manmademan
Member
wishful thinking, mostly.
A 'Confirmed XB1 Dev' has commented on this
http://www.reddit.com/r/xboxone/com...as_its_own_coherency_solution_similar/cbswrn3
http://www.reddit.com/r/xboxone/com...as_its_own_coherency_solution_similar/cbswrn3
Cool, never heard that before. Worthy of a new thread.
X1 has 1.31 TFlops actually, supposedly with 1.18 TFlops available to games (10% reserved for OS).
But yeah, doesn't change your point.
Don't pull things out of your ass. If course the garlic bus supports virtual memory -- that's how PRT works (a recent presentation even described PRT as page-fault tolerant GPU accesses)! You're certainly not going to so something as bandwidth intensive as texture sampling on the narrow bus.
ESRAM is also no L3 cache! It's wholly under developer control, but that means if you want to use it like an you'll have to so it yourself in software.
GCN cards contain a MMU that implements x86 style virtual memory (4kb pages among other things)
http://www.amd.com/us/Documents/GCN_Architecture_whitepaper.pdf
Page 4, paragraph 2.
Perhaps, feel free to do thisBut I think it's as bull as the DC-60fps.
But unlike DC, we've actually seen slivers of Killzone reaching 60fps.
Hmm.
The VGLeaks docs directly contradict this. They say the GPU is IO coherent, not cache coherent.
Perhaps, feel free to do this
At least they quote somebody directly this time.
Also interesting, are reddit's verifications legit? I'll add it if that's the case.
"Somebody had PM'ed me earlier linking to the Ars article on how the PS4 has a big advantage over the Xbox one due to hUMA. This was apparently said by some AMD marketing manager.
I haven't heard of hUMA until today, so I went to look it up."
What a dev. I don't know what it is, but we have it.
Was this on Ars also?
I haven't heard of hUMA until today, so I went to look it up."
What a dev. I don't know what it is, but we have it.
Was this on Ars also?
Manmademan
Member
a confirmed dev who has 'never heard of it' before today? but pulls some whitepapers and says "oh, it's the same thing, that german publication is lying to you?" why am I less than convinced here.
He didn't know what is huma. He is no xbone dev
Until he can show me the exact wording of the white paper im a little suspicious of this.
PuppetMaster
Member
Xbox devs have no sense of huma.
Krusenstern
Banned
He said he didn't know about hUMA and had to look it up.
How should I understand that?
Megaton
Brilliant!
Interesting story too, though I won't pretend to understand the details.
Or well, you know, he actually IS a XB1 dev...
I don't know dude, from his wording I understand he literally has no idea what huma means. I would assume a developer would know something like that.
Unless he's a pr person.
I would guess this. He showed up the moment the DRM meltdowns started happening.
zomgbbqftw
Banned
It is not credible that a developer on a console with UMA wouldn't know what hUMA is. Absolutely zero credibility. I am quickly coming to the conclusion that the "confirmed" developer is actually just a marketing person with a bit of technical knowledge.
Everything that comes from this "developer" is just rewriting MS marketing lines or glossing over weak points like this. That he either claims to have no knowledge of hUMA or actually doesn't is ridiculous.
Claude Kenni
Member
I don't think it's fair to put this entirely on them. GAF is to blame for a large part of this particular situation. Sensationalist topic titles that falsely attribute quotes like this one cause many people to accept false information as common knowledge. I would feel sorry for readers of this site as well because stuff like this happening has caused quite a bit of confusion on several issues. So many people don't look far beyond topic titles and one like this not being changed is inexcusable.
Knowing tech and knowing how the bullshit-bingo-people name it are two completely different things.
zomgbbqftw
Banned
hUMA has been a huge part of AMD's APU push, proper developers should know what it is and what it entails without having to look up a reference paper. This "confirmed dev" is likely a PR person if they don't know what hUMA is.
Vestal
Gold Member
what???
this is a forum and not a news organization.
The lack of real journalism in gaming is the real travesty. Sourcing a story from a gaming forum and another sites article without doing your own investigation towards the authenticity of an articles contents is not journalism. Its just click bating.
The apparent problem in many gaming news sites is the lack of real Journalist that take due diligence of getting all the facts, and the quotes to back those facts up. You simply can't make an article such as the one in the op attributing conclusions to a source without showing a direct quote that lead you to that conclusion.
Nothing excuses journalists from their duty to check their sources. And some haven't apparently even read what they are quoting.
Actually he knows that huma is, just not that it had a name. Ask devs what Larrabee is - many won't tell you in detail. Just because you are in tech doesn't mean you know every abbreviation out there. It's more important to understand how stuff works to fully exploit the possibilities.
We don't know if it is only for mp.
Sure thing it is not like hUMA is known in enginering circle.
He may be xbone game dev but probably isn't hardware dev
Nah, he really seems like he has no idea what it means. I mean if I was like him, knew the tech but not the term, I wouldn't say "I looked it up and it seems to be.. etc"
To me it sounds like he had no prior knowledge of it at all. "The way I understand it..." you know.
Claude Kenni
Member
But why does that excuse the role GAF plays in situations like this? Many people come here for gaming news. When a topic is posted like this it's representing itself as news and you can see how people accept stuff like the topic title as common knowledge. That's a pretty big issue when this topic has over 1000 posts and far more views but those that simply read the topic title as many do might actually be less informed than if they had not.
Topics that possibly misinform should not get a pass just because this is a forum. Topic creators need to read carefully what they post instead of rushing topics with sensational titles and mods need to make sure topic titles accurately reflect the actual information contained within. How is it acceptable at all for this topic to still have the same title attributing an article's unsure conclusion without a quote from AMD as a quote from AMD?
What unsure conclusion?
The author of the heise article had an interview with an AMD representativ for the c't magazine. It was confirmed to him that Xbox One doesn't have hUMA.
He writes an article on said news, as this is a change to what previously was accepted wisdom.
GAF creates thread based on said news article.
Where is the misinformation?
you can be gui programmer, ai programmer and so many different things and have little clue about game engine
.developer is such a wide term to be easily misused...
you can be gui programmer, ai programmer and so many different things and have little clue about game engine
developer is such a wide term to be easily misused...
Why misuse? A dev is a dev, no matter what the dev devs.
Vestal
Gold Member
While I agree with your sentiment in regards to how some use GAF, at the end of the day it still remains a gaming forum in which topics are created not by journalist but by average gaffers. While I agree that the thread title is extremely sensationalistic, at the same time it details the assertions made in the article within.
Like you can imagine I don't give the article in the OP much weight simply because the author did not deem necessary to back up his assertions with direct quotes from his source. That is just shitty journalism and gives the sense of clickbate.
But as evident by the 1000+ posts here, a lot of gaffers as well as some other "journalist" sites are willing to take the article at face value without questioning it. We need to hold gaming journalist to the same standard as regular news journalist.
Its an forum, you post rumors and news.
Also posts about how do you like this or that.
Its internet , you need to be an adult and believe what you want to believe.
I find the rumors interesting in every rumor is a bit truth.
But i know that unless confirmed its a rumor.
So i dont know why you are al worried and frustrated about, no need to come to my defence.
I can choose for myself what i accept as truth or not.
Vestal
Gold Member
the problem with the article is the lack of facts to back up the conclusions drawn by the author. What exactly did his source say that made him draw these conclusions.
The same skepticism is applied to regular news articles, you can't simply say hey I spoke to a congressman and he is not going to support X, without including a quote. You post that crap and you won't be a journalist for long.
zomgbbqftw
Banned
you can be gui programmer, ai programmer and so many different things and have little clue about game engine
developer is such a wide term to be easily misused...
No doubt, but this developer clearly isn't involved in the hardware development or game development on Xbone.
It does matter. Absolutely it matters. MS are trying to pass this guy off as an expert and voice of authority on a public forum when his post about hUMA shows he is pretty clueless. It's a classic MS tactic of bygone years they employed in the HD DVD/Blu-ray fiasco, they would send out their employees to high profile forums to spin and undermine legitimate concerns that people had about HD DVD. Now they are extending that to Xbone, why else is Albert Penello on GAF, he serves the same role Amirm did for HD DVD.