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A few problems in your comment: 1) The article text is wrong (and doesn't match the pics of the slides). The chip demonstrated today is Knights Corner which is

A few problems in your comment: 1) The article text is wrong (and doesn't match the pics of the slides). The chip demonstrated today is Knights Corner which is a new part, not the older Knights Ferry SDV. 2) When counting flops we need to distinguish between single precision flops and double precision flops. You're comparison isn't valid -- Knights Corner was shown sustaining over 1TF on a double precision code. Nvidia's most recent flagship GPU has a theoretical peak of 515GF/s but sustains less than 225GF/s on the same DGEMM operation. Knights Corner is sustaining 4-5x that, and this implies that it's theoretical peak is higher again. AMD's GPUs also cannot touch this with a single chip. Their dual chip 6990 has what looks like the same theoretical peak but far lower practical performance due to being more of a graphics part than a compute part (e.g. look at the cache structures). You are correct that these are real cores, each with a wide vector unit. If we wanted the equivalent of GPU "cores" we should multiply out by the vector width per core.

Retric 15y ago
This Intel chip has a theoretical max performance of 1TF/s actual benchmarks are clearly going to be lower than that. The only thing slightly interesting about this is x86 but considering the large vector unit and anemic cache your not going to be able to port high performance code to this without massive changes anyway. And while comparing new chips vs existing chips is always a tradeoff, looking at the Radeon HD 6970 released in Dec 15, 2010 which had 2.7 TFLOPs Single Precision and 683 GFLOPs Double Precision this is a relatively minor jump in single chip double precision performance and unless there releasing it next week it would probably still be far slower than it's competitors. That's also raw performance, considering this is a brand new architecture it's likely to have some significant bottlenecks limiting it's performance for the next 2-3 product cycles. PS: Considering so few details where provided it's hard to look at this as anything but Intel saying "Please don't port your code we will have competitive x86 chips out at some point in time."
- stuntprogrammer 15y ago
  It's doing 1TF sustained and no one ever sustains 100% of their theoretical peak, so we know the peak is higher than 1TF. Consider also the sandbagging of number of cores as "50+". How big is the "+"? In reality the design will have a larger number that is then binned by yield and so forth to give a range of SKUs, as usual. Next, you're comparing a sustained number on DGEMM with theoretical peaks on other machines. Nvidia sustains <225GF on DGEMM with Fermi so this is 4-5x. Last I looked, AMD were sustaining ~500GF with Cayman, so this is 2x, and a much easier machine to sustain perf on for other codes compared to Cayman. If you consider a potentially sandbagged 2x sustained perf to be "relatively minor" then so be it. There are few public details provided but many of us have been programming with the Knights Ferry SDV kit in preparation for this part. So we have experience with the tools, with the use of lots of similar cache coherent x86 cores, etc. I can tell you this -- it's much easier to work with this than GPUs, and I've written a ton of code on all kinds of whacky machines, production compute code on GPUs included.
  - sausagefeet 15y ago
    Where can I learn more about how all this hardware works?
  - onemoreact 15y ago
    I don't see any mention of this chip doing DGEMM at 1TF. Just that it's sustaining 1TF performance, but you can write assembler code that get's within 1% of theoretical peak flops if your not trying to get anything done but, if you have a source feel free to give it. (Not that that even means much, AMD's getting 80% of theoretical max FLOPS on that benchmark and I assume Intel would pick the optimum benchmark for it's chip even if they had to design the chip around the benchmark.) Also, I don't see anything that suggests it's anywhere close to a production chip. More important, Knights Ferry chips may help engineers build the next generation of supercomputing systems, which Intel and its partners hope to delivery by 2018. Not to mention your comparing a preproduction chip with a year old chip that's running on a 2 year old process when AMD, Intel, and Nvidia are about to do a die shrink.
    - stuntprogrammer 15y ago

Retric 15y ago

This Intel chip has a theoretical max performance of 1TF/s actual benchmarks are clearly going to be lower than that. The only thing slightly interesting about this is x86 but considering the large vector unit and anemic cache your not going to be able to port high performance code to this without massive changes anyway. And while comparing new chips vs existing chips is always a tradeoff, looking at the Radeon HD 6970 released in Dec 15, 2010 which had 2.7 TFLOPs Single Precision and 683 GFLOPs Double Precision this is a relatively minor jump in single chip double precision performance and unless there releasing it next week it would probably still be far slower than it's competitors. That's also raw performance, considering this is a brand new architecture it's likely to have some significant bottlenecks limiting it's performance for the next 2-3 product cycles. PS: Considering so few details where provided it's hard to look at this as anything but Intel saying "Please don't port your code we will have competitive x86 chips out at some point in time."

stuntprogrammer 15y ago
It's doing 1TF sustained and no one ever sustains 100% of their theoretical peak, so we know the peak is higher than 1TF. Consider also the sandbagging of number of cores as "50+". How big is the "+"? In reality the design will have a larger number that is then binned by yield and so forth to give a range of SKUs, as usual. Next, you're comparing a sustained number on DGEMM with theoretical peaks on other machines. Nvidia sustains <225GF on DGEMM with Fermi so this is 4-5x. Last I looked, AMD were sustaining ~500GF with Cayman, so this is 2x, and a much easier machine to sustain perf on for other codes compared to Cayman. If you consider a potentially sandbagged 2x sustained perf to be "relatively minor" then so be it. There are few public details provided but many of us have been programming with the Knights Ferry SDV kit in preparation for this part. So we have experience with the tools, with the use of lots of similar cache coherent x86 cores, etc. I can tell you this -- it's much easier to work with this than GPUs, and I've written a ton of code on all kinds of whacky machines, production compute code on GPUs included.
- sausagefeet 15y ago
  Where can I learn more about how all this hardware works?
- onemoreact 15y ago
  I don't see any mention of this chip doing DGEMM at 1TF. Just that it's sustaining 1TF performance, but you can write assembler code that get's within 1% of theoretical peak flops if your not trying to get anything done but, if you have a source feel free to give it. (Not that that even means much, AMD's getting 80% of theoretical max FLOPS on that benchmark and I assume Intel would pick the optimum benchmark for it's chip even if they had to design the chip around the benchmark.) Also, I don't see anything that suggests it's anywhere close to a production chip. More important, Knights Ferry chips may help engineers build the next generation of supercomputing systems, which Intel and its partners hope to delivery by 2018. Not to mention your comparing a preproduction chip with a year old chip that's running on a 2 year old process when AMD, Intel, and Nvidia are about to do a die shrink.
  - stuntprogrammer 15y ago