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AMD Unveils Vega GPU Architecture With 512 Terabytes of Memory Address Space (hothardware.com)

Posted by BeauHD on from the scale-to-size dept.

MojoKid writes: AMD lifted the veil on its next generation GPU architecture, codenamed Vega, this morning. One of the underlying forces behind Vega's design is that conventional GPU architectures have not been scaling well for diverse data types. Gaming and graphics workloads have shown steady progress, but today's GPUs are used for much more than just graphics. In addition, the compute capability of GPUs may have been increasing at a good pace, but memory capacity has not kept up. Vega aims to improve both compute performance and addressable memory capacity, however, through some new technologies not available on any previous-gen architecture. First, is that Vega has the most scalable GPU memory architecture built to date with 512TB of address space. It also has a new geometry pipeline tuned for more performance and better efficiency with over 2X peak throughput per clock, a new Compute Unit design, and a revamped pixel engine. The pixel engine features a new draw stream binning rasterizer (DSBR), which reportedly improves performance and saves power. All told, Vega should offer significant improvements in terms of performance and efficiency when products based on the architecture begin shipping in a few months.

73 of 125 comments (clear)

  1. 512TB of address space means nothing by Lisandro · · Score: 1, Insightful

    Most high end GPU cards available have 8Gb, a large number of budget versions settle for 4Gb, and only a few offer 16Gb. Marketing this as a stand out point is iffy.

    1. Re:512TB of address space means nothing by BigBuckHunter · · Score: 2

      Most high end GPU cards available have 8Gb, a large number of budget versions settle for 4Gb, and only a few offer 16Gb. Marketing this as a stand out point is iffy.

      What you will find is that most cards have only a fraction of their RAM as addressable, so a 16GB card either 4 or 8 gigs addressable. The increase to 512GB is a godsend to AI researchers and other fields with large datasets.

    2. Re:512TB of address space means nothing by Anonymous Coward · · Score: 5, Informative

      Lisandro you COULD RTFA, you know? It's even an effing meme around here.

      The HBCC gives the GPU access to 512TB (half a petabyte) of virtual address space and gives the GPU fine-grained control, for adaptable and programmable data movement. Often, more memory is allocated for a particular workload than is necessary; the HBCC will allow the GPU to better manage disparities like this for more efficient use of memory. The huge address space will also allow the GPU to better handle datasets that exceed the size of the GPU’s local cache. AMD showed a dataset being rendered in real-time on Vega using its ProRender technology, consisting of hundreds of gigabytes of data. Each frame with this dataset takes hours to render on a CPU, but Vega handled it in real-time.

    3. Re:512TB of address space means nothing by Anonymous Coward · · Score: 1

      yea thats 32 gig's in banks of 4 bankswitching

      even if you do not use it all just the wasted time and overhead saved is quite a bit in serious applications (and maybe even a few fps in gamez!)

    4. Re:512TB of address space means nothing by K.+S.+Kyosuke · · Score: 1

      Except for AMD cards with massive storage for (semi)fixed datasets... Kind of the reason for this, in fact.

      --
      Ezekiel 23:20
    5. Re:512TB of address space means nothing by Lisandro · · Score: 3, Insightful

      But this is not new at all. IIRC Nvidia's CUDA 5 already gives you 49 bits of unified address space. Don't really know the addressing limitations on previous AMD architectures, but I doubt it was substantially lower.

      Realistically, large address spaces when you can only practically fill 0.05-0.1% means little for performance. I don't want to attack AMD with this, who usually manufacture really good GPU hardware, but this sounds like a marketing gimmick and nothing more. I particularly enjoyed the "hours to real-time" comparison... against a CPU.

    6. Re:512TB of address space means nothing by sexconker · · Score: 2

      What you will find is that most cards have only a fraction of their RAM as addressable, so a 16GB card either 4 or 8 gigs addressable. The increase to 512GB is a godsend to AI researchers and other fields with large datasets.

      Nope.

      1: The GPU addresses the whole damn pool.

      2: We're talking about 512 TB, not GB.

      3: They're not planning to release a card with 512 TB of RAM, but they are releasing professional cards with lots of RAM (8 GB, 16 GB, or more) AND onboard connections for flash storage (SSDs). Vega will likely continue and extend this. By having a huge address space, you simply have the ability to keep the entire dataset in your cache on the card. The memory controller then decides what needs to live in the fast HBM2 chips at any given moment. You don't need to use PCIe bandwidth, go through the CPU, or (gasp) go to disk storage to get your dataset onto the card for processing after the initial load. You don't need to manually load pieces into or out of the GPU's memory. You just load your shit once and tell it to fucking go.

    7. Re:512TB of address space means nothing by Cmdln+Daco · · Score: 1

      You just spend two hours loading everything into the GPU's memory. Then you start managing it, updating what parts of it change, etc.

      That PCIe bandwidth you mentioned? It's pretty scanty when you're shuttling 512 TB of data through it.

    8. Re:512TB of address space means nothing by unixisc · · Score: 1

      2^64 is 1.8x10^19. 1TiB is 2^40. So any 64 bit addressing scheme should at least cover 2^63 or 1,048,576TiB, assuming 1 address bit is sacrificed for the firmware or whatever else is needed.

      So 512TiB is nothing, given what a flat 63 bit address space is capable of achieving. Also, supporting it on the address ain't difficult, given that there have been both data-address multiplexed lines as well as address-multiplexed lines.

    9. Re:512TB of address space means nothing by K.+S.+Kyosuke · · Score: 1

      Address space is nice, physical cells even better. Unlike nVidia's CUDA, APUs at least give you *actual* unified address space, including memory protection, and SSG Radeons push the cells closer to the chip on the other side of the PCIe bus.

      --
      Ezekiel 23:20
    10. Re:512TB of address space means nothing by K.+S.+Kyosuke · · Score: 1

      I think he meant GPU/CPU memory moves without remapping pointers, as long as the GPU also has some MMU hardware available. Just because all the data doesn't actually fit into GPU's local memory at once doesn't mean you can't successfully pretend that it does.

      --
      Ezekiel 23:20
    11. Re:512TB of address space means nothing by Anonymous Coward · · Score: 3, Informative

      They're actually using NVMe drives as the extra "memory". This works out well for huge datasets where you take a performance hit streaming it from the host. Load up the data on one of those 4GiB/s NVMe SSDs. They already have a product out that does this and it makes certain workloads much faster. Just waiting to see an 8x PCIe 4.0 NVMe XPoint SSD. Will be wicked fast for what they use it.

    12. Re: 512TB of address space means nothing by Anonymous Coward · · Score: 3, Informative

      There is already technology available to feed this monster. Things like the EMC DSSD can have 1/2 PB of NVMe flash connected via a PCIe bridge, and presented as a single shared memory mapped space to an entire rack if servers. I assume that is the use case for these cards, mostly in the supercomputing space.

    13. Re:512TB of address space means nothing by Lisandro · · Score: 1

      Oh, it is nice, don't get me wrong :) I'm just saying that promoting this as a dealbreaker is insane.

    14. Re:512TB of address space means nothing by Lisandro · · Score: 2

      Pretty much all of it. I'm having a hard time finding out the number of addressing bits supported by, say, an Arctic Lake (4xx) GPU, but considering that AMD's GCN offered unified memory on the entire 64 bit space since 2011 and nVidia offers 49 bits of unified address space since CUDA 5 it surprises me that someone tried to make a selling point out of this feature.

      They went as far as comparing a CPU render against their new GPU. WTF.

      The only reason i can imagine someone would try to push this feature is that 512TB sounds like a huge number. There's no practical application for it in the near future, and any benefit of such a large addressing space you already got on previous architectures, both from AMD and its competition.

    15. Re:512TB of address space means nothing by Lisandro · · Score: 1

      Don't be a moron. You already got virtual memory mapping over huge address spaces on previous-gen GPU products, both from AMD and nVidia. Vega looks like a nice architecture but all these hyperbolic performance claims based solely on having 512TB of addressable space are utter bullshit. I'm actually surprised that most people here can't tell the difference.

      Ah, and i'm pretty sure that "future-proofing" a GPU architecture that will be obsolete 5 years from now was certainly not a consideration for AMD engineers working on this.

    16. Re:512TB of address space means nothing by K.+S.+Kyosuke · · Score: 1

      It can be once you get used to the convenient programming model. The same thing happened a quarter century ago regarding the segmented memory model.

      --
      Ezekiel 23:20
    17. Re:512TB of address space means nothing by Lisandro · · Score: 1

      You really need to re-read my parent post.

    18. Re:512TB of address space means nothing by Lisandro · · Score: 1

      Anyway, it doesn't mean the cards themselves would need to have such huge amount of memory, it means they are now able to handle a memory address space that vastly exceeds their physical memory. Graphics cards don't need to have everything in local memory.

      I've replied this below a good number of times below, but for completeness sake: this is not new. Not even for AMD, which i'm unable to find the exact number of addressable bits for each GPU family but they all support unified virtual memory with 64 bits CPUs since the days of the HD7700. Hell, Linux has support for this feature since 3.20.

      nVidia? CUDA 5 has you covered as well.

      My point is: current GPU offerings can already address way, way more memory than they usually physically carry. No idea why someone would push this as a selling point other than 512GB sounds like a large number to people who don't know better.

    19. Re:512TB of address space means nothing by Lisandro · · Score: 1

      512TB, sorry.

    20. Re:512TB of address space means nothing by Lisandro · · Score: 1

      AMD has supported this for years.

    21. Re:512TB of address space means nothing by sexconker · · Score: 2

      You don't understand.

      The architecture can address that much, but the actual product will only address what's available.
      There will be on-package HBM2 and the ability to connect to on-board (but off-package) storage in the form of fast flash.

      512 TB of addressable space is just future proofing to allow for seamless work with a dataset regardless of whether it's on the 16 GB of ball-smackingly fast HBM2, on the SSD on your RadeonPro card, or in your system memory (or potential even abstracted out to disk storage). The drivers and GPU's memory manager handle moving the data around as you work on it. You shouldn't have to explicitly manage the dataset and thus not have to load it twice. In a worst-case scenario you'll be moving stuff back and forth over the PICe bus, just as you do now. But that'll only happen if you're trying to be stupid or your dataset exceeds the capacity of the on-board memory and SSD.

      Also keep in mind that AMD will almost certainly be releasing APUs (their CPU+GPU combos) with Vega cores and HBM2 memory. This is all an extension of their previous push for HSA (heterogeneous system architecture) - essentially tying CPU and GPU and memory and everything else closely together and letting everyone talk to each other in the most efficient way possible.

    22. Re:512TB of address space means nothing by Cealestis · · Score: 1

      This isn't so the GPU can address just vram, it allows their new GPU HBM2 cache to directly address data in memory and disk as well. For big simulations on a cluster utilizing GPUs this can be a huge benefit.

    23. Re:512TB of address space means nothing by WorBlux · · Score: 1

      Or maybe custom super-computers, a lat HP's "The Machine", with gobs and gobs on non-volatile system memory (persistent RAM), or some other configuration where the Vega chip can access a lot of other memory over a dedicated fast fabric.

    24. Re:512TB of address space means nothing by K.+S.+Kyosuke · · Score: 1

      On the programming side, yes. Of course they have. But even in AMD's APU hardware, proper memory architecture was delayed at least until Carizzo. You still need proper hardware to properly take advantage of it.

      --
      Ezekiel 23:20
  2. Re:You know, for Gamers! by Anonymous Coward · · Score: 1, Informative

    Framerate on the outside doesn't matter to the lifeforms inside the simulation.

  3. 2017 might be AMD's year by ITRambo · · Score: 3, Interesting

    With Rizen coming out soon and a new GPU design that looks very advanced, AMD is set to make substantial progress in market share, as long as they don't screw up. I'm rooting for them. I had switched all of our shops new PC's to Intel when they released their 6th gen Core series as AMD was just too far behind. Teh consumer PC's were all AMD for the past five years or so. I wanna go back to AMD, as long as the new stuff performs. Don't let us down AMD!

    1. Re:2017 might be AMD's year by fisted · · Score: 2, Informative

      But 2017 is already the year of the Linux desktop...

      --
      CLI paste? paste.pr0.tips!
    2. Re:2017 might be AMD's year by Highdude702 · · Score: 1

      on AMD Hardware.

    3. Re:2017 might be AMD's year by Cmdln+Daco · · Score: 1

      1982 was the year of AMD hardware.

    4. Re:2017 might be AMD's year by Z80a · · Score: 4, Funny

      Linux will never be on the desktop.
      10 years from now, the linux powered terminators being commanded by the linux powered skynet, riding their flying linux powered bikes will still use Windows on their desktop computers, while performing experiments on installing linux on living people.

    5. Re:2017 might be AMD's year by The-Ixian · · Score: 1

      I have only built AMD systems for nearly 20 years. My current AMD system is almost 4 years old now but still drives 5760x1080 pixels in most modern games with reasonable quality and frame rate (30fps or more). It also boots in less than 10 seconds and is an all-around snappy computer. I have not yet found a reason to upgrade.

      --
      My eyes reflect the stars and a smile lights up my face.
    6. Re: 2017 might be AMD's year by ezelkow1 · · Score: 2

      Sure as long as you only played their one bland boring dx12 game, ashes of the singularity. Anything else and dual r480's still usually get smoked by a standard 1080, let alone whatever the ti version might be. Hell they just about match a 1070

      http://arstechnica.com/gadgets...

  4. News for nerds? by Orgasmatron · · Score: 5, Informative

    The "news for nerds" version of this story's headline is "AMD Unveils Vega GPU Architecture With 49 bits of Memory Address Space"

    --
    See that "Preview" button?
    1. Re:News for nerds? by Luthair · · Score: 2

      What we really need to know is if they tested a Beowulf cluster of them.

    2. Re:News for nerds? by Kjella · · Score: 2, Insightful

      The "news for cynics" version of this story's headline is "AMD unveils yet another set of powerpoints". Where is (Ry)Zen? Where is Vega? Every month is another month Intel and nVidia rule unchallenged on the high end. We need actual product on the shelf, not more tech demos. And I bet so does AMDs financials, you have to actually hard launch it before you get any revenue. I'm a bit hyped out, now it's more like hoping for a miracle.

      --
      Live today, because you never know what tomorrow brings
    3. Re:News for nerds? by lcllam · · Score: 1

      And whether it runs Crysis(tm).

    4. Re:News for nerds? by Cmdln+Daco · · Score: 1

      I think he meant SKUs in retail outlets and in eShops that can be ordered, not vapor-hardware at a trade show.

    5. Re:News for nerds? by CanadianMacFan · · Score: 1

      Did they blend a Beowulf cluster of them?

    6. Re:News for nerds? by Areyoukiddingme · · Score: 1

      Strange vapor-ware[sic]. Did you even read the article? The CPU exists, the motherboards exists, the coolers exists.

      Well one of them does, at least...

  5. 512 terabyte addr space should B enough 4 anybody by youn · · Score: 1

    Is that how the saying goes? I am not sure :p

    --
    Never antropomorphize computers, they do not like that :p
  6. Messing up the meme. by hackwrench · · Score: 1

    The meme around here is that nobody reads the articles.

    1. Re:Messing up the meme. by ArylAkamov · · Score: 1

      Why bother reading when you can shitpost?

  7. Re:Probably's not how many memory chips you can fi by Lisandro · · Score: 1

    I really want to see AMD releasing a CPU competitive with Intel's latest offerings. I love my 8-core FX, but the real reason I bought it is that it costs almost 1/3rd compared to the competition.

  8. Re: You know, for Gamers! by dfeifer · · Score: 1

    I want my holodeck..

  9. We been here before... by __aaclcg7560 · · Score: 1

    The early 2000's was the last time had a Nvidia Geforce video card (256MB) with more RAM than my PC (192MB).

    1. Re:We been here before... by __aaclcg7560 · · Score: 1

      Well, that shouldn't have happened under normal conditions.

      I was a professional videogame tester at the time.

      You probably bought a card way out the league of your PC.

      Back then I was probably upgrading my video cards every year. After I rebuilt my gaming PC for Windows Vista in 2007, I upgraded my video cards every three years.

  10. Re:But, but, but... by __aaclcg7560 · · Score: 1

    I had a computer instructor in the early 1990's who said that 4GB on a 32-bit processor was enough RAM for anyone to use. For the most part, he was correct. I had a 4GB system for nine years before I upgraded to a new motherboard with 8GB. The only time I ever use more than 4GB is when I'm playing a videogame or encoding video.

  11. Re:You know, for Gamers! by Cmdln+Daco · · Score: 1

    And we are completely safe from said lifeforms, since nothing they do will ever emerge.

    Person A: "Is it bricked, or just really really busy?"

    Person B: "Hmmm, maybe if we wait a little longer..."

  12. Re:Forget 512TB of address space by Cmdln+Daco · · Score: 1

    Are they really allocating 49 pins on the CPU package to the address bus?

    Will there be Vega-SX parts that are in much cheaper packages and only put out 40 pins?

  13. Re:trash posting by hackwrench · · Score: 1

    Much of the time the summaries give enough additional information to what some commenters have learned from other sources for them to make useful comments. Some commenters aren't most commenters though, and sometimes metacomments like these are in order.

  14. Re:Probably's not how many memory chips you can fi by tginouye · · Score: 1

    That's why my FX 8350 stays at home in it's "Safe space". Those mean intel CPUs are always out picking fights.

  15. Re:Probably's not how many memory chips you can fi by K.+S.+Kyosuke · · Score: 1

    ...in any antiquated single-threaded application, sure.

    --
    Ezekiel 23:20
  16. Re:trash posting by ArylAkamov · · Score: 1

    I wasn't talking about you, if you were thinking that. Besides, meta comments are best comments.

  17. 512TB? Why? by Khyber · · Score: 1

    What's the point? By the time we hit that amount of memory on a GPU, we're looking at this architecture being entirely obsolete.

    Should've just said "We're slapping 1TB on this bitch!" and been done with it. No point in fussing about the scalability of the architecture when we're likely never going to see it hit full potential until long after its deprecated (AGP slot, anyone? When PCI-E cards came out, we'd barely even thought of saturating a 4X AGP slot.)

    --
    Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
    1. Re:512TB? Why? by smallfries · · Score: 1

      If you have a small address space then you need to write code that manually pages / caches the working set for an algorithm from storage. If you have a large address space then you use an interface similar to mmap and address the large dataset directly. It makes the code easier to write, and means that the paging / caching can be handled in hardware, where there are opportunities to speed it up.

      --
      Slashdot: where don knuth is an idiot because he cant grasp the awesome power of php
    2. Re:512TB? Why? by Lisandro · · Score: 1

      Keep in mind large address spaces were here long before Vega. Hell, AMDs own "Graphics Core Next" architecture already supports flat 64-bit addressing, an that's been out since 2011.

    3. Re:512TB? Why? by squiggleslash · · Score: 2

      The Intel i386 had a 32 bit address bus back in the late eighties. Nobody could afford 4Gb back then for the type of machine that would have one. I had an Amiga with 5Mb of RAM and people ooh'd and aah'd about that.

      But it didn't matter. Early 32 bit machines didn't use the top bits to support more RAM, they used it to support more functionality. Flat address spaces, with VM used to locate memory exactly where it needed to be.

      I suspect the aim is similar here too.

      --
      You are not alone. This is not normal. None of this is normal.
    4. Re:512TB? Why? by Bob+the+Super+Hamste · · Score: 1

      AGP, try VESA Local Bus when talking about a limited use bus that was deprecated quickly. Add in that VLB cards were a real bitch to get in to the slots, or at least that is my most vivid memory of them.

      --
      Time to offend someone
  18. Re:Good Video Analysis of the data so far-vGPU. by Khyber · · Score: 1

    Well, don't bother looking at any Microsoft Benchmarks. They killed RemoteFX performance by half in Server 2012. I still run my stuff on 2008R2 for this reason.

    --
    Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
  19. Re:Probably's not how many memory chips you can fi by Lisandro · · Score: 1

    Not really, sadly enough. Intel's single core performance is so above AMDs that for most computational tasks it makes little impact.

  20. Re:But, but, but... by 91degrees · · Score: 1

    (Really, anyone believes his "foundation" is anything but a tax avoidance scheme? Don't be stupid.)

    How would that even work?

  21. Re:You know, for Gamers! by MancunianMaskMan · · Score: 1

    yes, after all, what happens in Vega, stays in Vega.

  22. Let's get real here by zifn4b · · Score: 2

    Someone check me on my logic here. The way I read this article is that AMD has created a new architecture with a memory controller that can address 512TB of memory address space. That's great and all but are we going to see cards any time in the near future with 512TB of GDDR on them? Not likely. How many years away are we? Who knows. It seems to me this is highly theoretical and possibly to put pressure on the memory industry to innovate on even more dense memory to push graphics even farther to the limit. It could also be to get some investor interest in the next "big thing".

    Side question: How did AMD validate that their architecture works without actually being able to fabricate an actual board in practice, simulation?

    --
    We'll make great pets
    1. Re:Let's get real here by Lisandro · · Score: 1

      Side question: How did AMD validate that their architecture works without actually being able to fabricate an actual board in practice, simulation?

      You don't need to actually hook up memory to see if a memory bus works correctly. I used to test addressing on 8-bit CPUs using a Tektronix logic analyzer back in college.

    2. Re:Let's get real here by zifn4b · · Score: 1

      AMD can actually connect SSDs directly to a GPU. So you can have your 32GB of HBM2 memory with ridiculous bandwidth, and a multi-TB SSD on the other side of the board

      That's a neat idea. It's like you turn a PCI-E SSD into a modern day Voodoo 2 card

      --
      We'll make great pets
  23. Re:Probably's not how many memory chips you can fi by pezezin · · Score: 1

    Take a look at this: https://www.cpubenchmark.net/c... It's faster than even the latest i5-6600, and cheaper. Only the i7's are faster. And don't tell me about single core performance, it's 2017, any program I care about is multithreaded. Now if you talk about energy consumption, you may have a point...

  24. Re:512 should be enough for anybody.... by fbobraga · · Score: 1

    WTF ho made AMD PR is smoking?!?!

  25. Re:You know, for Gamers! by fbobraga · · Score: 1

    the wait really worth-ed: my own "The Matrix"!

  26. First step towards integrated CPU by ET3D · · Score: 1

    Given the relative sizes of CPU's and GPU's, it makes sense that an 'APU' will be a GPU with a bundled CPU, rather than the other way round. Having a large address space is one requirement for doing virtual memory on a card.

  27. 512 TB should be enough for any *CLUSTER*... by DrYak · · Score: 1

    Fixed the title for you.

    And I think that's genuinely the point of this:
    it would be possible to run a whole cluster of compute nodes with VEGA GPUs,
    and have all the data within a single unified address space across the whole cluster.

    Just throw in a few IOMMU to handle access rights, and a fabric like Infiniband, or some PCI-E based one.

    For bonus point have the storage it self being memory mapped non-volatile RAM (X-Point, etc.)
    (But then you DO run out of address space - clusters tend to have data in the peta-byte range).

    --
    "Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
  28. AMD ruined ATI with shit drivers by BeCre8iv · · Score: 1

    Then they effectively discontinue a whole range of DX11 4gb GPUs before even writing working drivers. Waste of time, money and silicon.

    --
    This perpetual motion machine Lisa made is a joke, it just keeps getting faster and faster. - Homer
  29. 512TB of ADDRESSABLE memory!!! Seriously, RTFA. by Calabacin · · Score: 1

    It's funny how not RTFA in Slashdot is even a meme but yet I can see that 95% of the people here didn't read it. The 512TB number is the amount of ADDRESSABLE memory, which means that you can reserve for example 300Gb of that memory to read a texture file that big. Then, as you start reading it, a secondary controller will transfer data there from main memory, directly from disk or from wherever. To you it will be as if you were reading a 300GB block from Video memory and thanks to that external controller (IOMMU, DMA, etc.) that transfer will be super fast. While you are doing that other application will be doing the same with a 1TB block. Both will be easily accesible at the same time thanks to having 512TB of ADDRESSABLE memory. Each of those applications will only use a part of the total REAL memory for this access. No more manual overlay/pagination will be necessary.

    This technique is commonly used in modern systems, but it was revolutionary when it first appeared. AMD has now brought it to the GPU now so that it can be used with many more applications. Apparently they are bringing the CPU to the GPU instead of the usual other way around.

    This new GPU also has "over 200 new features", for those who say it's nothing new.

    Not a fanboy or anything, but all these rants that could all be avoided reading the article or paying attention simply got to me. Sorry about that.

    --
    How much wood would a woodchopper chop if a woodchopper would chop wood?