back to article Amazon's new EC2 compute instances run on SECRET INTEL CHIPS

Amazon Web Services has raised the stakes for high-performance cloud computing with new, compute-optimized instance types for its Elastic Compute Cloud (EC2) service. The C4 instance types were first announced at the cloud kingpin's AWS re:Invent conference in Las Vegas in November. Expanding on the earlier C3 instances, C4 …

  1. thames

    Number of cores?

    "It delivers 18 E5-2666 cores for a total of 36 vCPUs – more than some versions of Linux can support."

    I'm not sure what the limitation is there unless you are talking about 32 bit versions of Linux, where they often limit the number of cores to 8. Of course 32 bit servers are probably not that common these days (at least with Linux). On 64 bit server versions, 256 cores is a more common default.

    If I recall correctly, the limit on number cores can be changed, but the distros usually set a default based on RAM usage (tables for tracking cores, if I recall correctly). A really high default number (e.g. thousands of cores) is possible, but it's less efficient on smaller systems.

    1. Anonymous Coward
      Anonymous Coward

      Re: Number of cores?

      Remember, these are Xen-based machines. I think it's a limit between the version of Xen and the version of the Linux kernel running the dom0.

      Some setups like Citrix' XenServer uses a 64-bit Xen kernel with a 32-bit PAE Linux dom0, in an attempt to keep the control plane as compact as possible.

  2. bazza Silver badge

    Pedant Alert

    AVX2 is 256 bits wide, not 256 bytes.

    That is unless Intel have done something amazingly customised for Amazon, but they'd have had to charge $quillions for it.

    AVX2 actually pretty good. It finally has an instruction set on a par with (though still not quite as good as) Altivec found in the sort of PowerPC processor in an iMac G4. It illustrates just how much Intel have depended on ramping core speed and memory subsystem performance. That takes 100s of millions of transistors for all those caches, decoders and pipelines; expensive. They've neglected the more elegant but easier side of CPU design - the instruction set.

    1. Crazy Operations Guy

      Re: Pedant Alert

      But adding instructions gives you very little in the near-term. There is too much that has to be done before any benefit is improved:

      -First new compilers need to be built

      -Then you'd have to re-compile new OS kernels and maintain multiple version (One for each version of the instruction set)

      -Then there is the effort of maintaining application binaries for each version of the instruction set or include quite a bit of bloat to determine what chip is in the system and branch if its supported or not (Of course a JIT-compiled language would alleviate the needs of this, but still...)

      The only reason Apple was able to do such things was that they has unilateral control over every layer of the system from the silicon to APIs. This allows them to make changes in parallel so that the Instruction set and OS take full advantage of each other (Proc is optimized for new OS features, OS fully utilizes every improvement in the silicon). Add this to the fact that they locked versions of the OS to machine models and you can make all the changes to the instruction set you could ever want.

      However this would never work on a free system where you have choice of OS and hardware can be heavily customized for your purposes.

      1. petur

        Re: Pedant Alert

        You mean like SSE & co... it didn't take long to have support for those, Intel offers a compiler that always offers support for the latest greatest, and others follow not too far off.

      2. bazza Silver badge

        Re: Pedant Alert

        It's not so bad from an operating system point of view. These sorts of instructions are of little use to the OS. All it needs to do really is to include whatever extra registers there are in the context switching.

        Applications aren't too bad either; AVX is best used with something like Intel's IPP/MKL libraries; the right sort of auto update will install the relevant dlls, etc. Intel write those libraries specifically so that app developers don't have to think too hard about the problem. Ok, so the libraries aren't free, but using them in one's app allows you to get the maximum performance with the minimum fuss; a good way of standing out from the crowd. And if one is dead set on writing ones own routines from scratch, using Intel's compilers is a good way of getting compiler support as soon as the silicon goes on sale.

        Chip manufacturers generally are well aware that if they don't provide good software support for their new silicon they'd lose out in the market place. It's up to software devs to make early use of that support to maximise the value of their own products.

  3. Anonymous Coward
    Anonymous Coward

    No big deal

    The max clock rate for regular/turbo mode are controlled by microcode on the chip which can be rewritten by Intel. The limits exist to avoid exceeding max power and maintain temperature, but if someone is willing to provide it more power and better cooling...

    Amazon effectively ordered factory overclocked chips from Intel. You can too, if you're willing to order in quantities of 100K or more at a time :)

  4. Voland's right hand Silver badge

    Lovely part number

    Lovely part number. Just drop the 2 from the front.

  5. Carlie J. Coats, Jr.

    VM interference with AVX2?

    Note to Crazy Operations Guy: the Intel compilers already support AVX2.

    However. I have experience running the WRF meteorology model on the previous-edition SandyBridge cores, and found that the performance increment from using the SandyBridge AVX instruction set (as opposed to the Nehalem SSE4.2) was negligible. This is as opposed to "real" hardware, where AVX gives WRF a 30% boos over SSE4.2 on SandyBridge, and where it gives a 70% boost to well-coded computational fluid dynamics apps. Given the Amazon VM environment, I still have the question: does Haswell-EP help _in_this_VM_environment_ ??

  6. Jimbo in Thailand
    Joke

    Yeah... but will it play Crysis?

    Sorry, I couldn't resist!

POST COMMENT House rules

Not a member of The Register? Create a new account here.

  • Enter your comment

  • Add an icon

Anonymous cowards cannot choose their icon

Other stories you might like