Efficiency Gets Another Boon: Parallel Kernel Support

In GPU programming, a kernel is the function or small program running across the GPU hardware. Kernels are parallel in nature and perform the same task(s) on a very large dataset.

Typically, companies like NVIDIA don't disclose their hardware limitations until a developer bumps into one of them. In GT200/G80, the entire chip could only be working on one kernel at a time.

When dealing with graphics this isn't usually a problem. There are millions of pixels to render. The problem is wider than the machine. But as you start to do more general purpose computing, not all kernels are going to be wide enough to fill the entire machine. If a single kernel couldn't fill every SM with threads/instructions, then those SMs just went idle. That's bad.


GT200 (left) vs. Fermi (right)

Fermi, once again, fixes this. Fermi's global dispatch logic can now issue multiple kernels in parallel to the entire system. At more than twice the size of GT200, the likelihood of idle SMs went up tremendously. NVIDIA needs to be able to dispatch multiple kernels in parallel to keep Fermi fed.

Application switch time (moving between GPU and CUDA mode) is also much faster on Fermi. NVIDIA says the transition is now 10x faster than GT200, and fast enough to be performed multiple times within a single frame. This is very important for implementing more elaborate GPU accelerated physics (or PhysX, great ;)…).

The connections to the outside world have also been improved. Fermi now supports parallel transfers to/from the CPU. Previously CPU->GPU and GPU->CPU transfers had to happen serially.

A More Efficient Architecture ECC, Unified 64-bit Addressing and New ISA
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  • SiliconDoc - Thursday, October 1, 2009 - link

    Nice consolation speech.
    I guess you expected " you're right ", but somehow lying to make you feel good is not in my playbook.
    Now, next time you don't take it so seriously as to reply, and then still, be pathetic enough to get it wrong. Hows that for a fun deal ?
  • Maian - Wednesday, September 30, 2009 - link

    Where's snakeoil when you need him... I don't give a shit about vendor, but the flame wars here are hilarious :D
  • Lifted - Wednesday, September 30, 2009 - link

    What flame war? It's just a single nut barking at everyone for no reason. If he has a problem with the article he's sure making it difficult to figure out what it is with all his carrying on and red rooster nonsense.

    Does anyone (besides the nut) actually care what is said in this article? It's simply something to pass the time with, and certainly not worth getting upset over. Is the nut part of the nvidia marketing machine or merely a troll? It almost seems as if he's writing in a manner as to cover up his true identity. Yes silicondoc, it IS that obvious.
  • SiliconDoc - Thursday, October 1, 2009 - link

    Wow, a conspiracist.
    Well, for your edification, you didn't score any points, since the readers here get all uppity about what's in the articles, so they have shown a propensity to care, even if you're just here to pass the time, or lie your yapper off for the convenient line it provides you for this momment.
    Usually, the last stab of the sinking pirate goes something it like: " It doesn't matter !"
    Then Davey Jones proves to 'em it does.
    -
    Nice try, but the worst problem for you is, it matters so much to you, you think I'm not me. NOW THAT's FUNNY !
    ahhahahahaaha
  • ClownPuncher - Wednesday, September 30, 2009 - link

    Aspbergers.
  • Kaleid - Wednesday, September 30, 2009 - link

    No, most people with Asperger's are highly functional. This is something else.
  • Finally - Thursday, October 1, 2009 - link

    It's Rain Man?
  • tamalero - Friday, October 2, 2009 - link

    its assburgers, google it.
  • redpriest_ - Wednesday, September 30, 2009 - link

    I can't help but note for the record that um, the card isn't out yet, so how can they win when no one knows when you can actually buy one yet? And for the record, I have a 5870 in my system, right now, that can play games....right now. I went to a retail store and bought it. That's how simple it was. I know you've been posting tons of FUD in the other review forums about how it's unavailable etc etc but the fact is, it IS available, and multiple people can own one.

    Also, let me state for the record that I have owned nvidia GPUs in the past so that I'm vendor agnostic. I buy whatever solution is available and better. KEY POINTS: AVAILABLE. BETTER.
  • SiliconDoc - Thursday, October 1, 2009 - link

    Here's how they can win, here the NVidia master holds FERMI up for all to see !

    http://www.fudzilla.com/content/view/15762/1/">http://www.fudzilla.com/content/view/15762/1/

    Aww, dat too bad for the wittle wed woosters. It really is real, little red lying hoods.

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