On 07/15/2010 12:07 PM, Zoltan Boszormenyi wrote: > JD írta: >> On 07/15/2010 11:23 AM, Michael Miles wrote: >> >>> On 07/15/2010 12:18 AM, JD wrote: >>> >>>> On 07/14/2010 11:41 PM, mike cloaked wrote: >>>> >>>> >>>>> On Thu, Jul 15, 2010 at 5:27 AM, john wendel<jwendel10@xxxxxxxxxxx> wrote: >>>>> >>>>> >>>>> >>>>>> Agreed that an OS kernel hasn't much use for a GPU. But it should be >>>>>> easy to add a small general purpose CPU (ARM or Intel Atom) and a couple >>>>>> of usb ports to the card and move X completely to the video card. Just >>>>>> like a remote X server only in the same box. >>>>>> >>>>>> I really think the OP was referring to having user mode code take >>>>>> advantage of the high processing power of modern GPUs. It works now, but >>>>>> could be improved if the OS contained specialized scheduling support for >>>>>> these kinds of jobs. >>>>>> >>>>>> >>>>> I understand that the GPU has no page faults, and is missing many of >>>>> what we regard as the essential functions of a normal processor? Also >>>>> getting large amounts of data in or out of the GPU is slow - it is >>>>> fast partly because there is a lot less overhead compared to a single >>>>> processor and partly from the advantage of multiple cores. I was >>>>> speaking to someone who has been working with GPU processing for >>>>> several years and was skeptical about getting code to run reliably >>>>> across different GPUs... and of course CUDA is vendor specific as fa >>>>> as I know? So speed gain is dependent on the kind of processing needed >>>>> but if anything goes wrong then it can easily crash the system. >>>>> >>>>> Anyone had any experience with using the GPU could perhaps comment? >>>>> >>>>> >>>> Sorry to barge in this late into this thread.... >>>> Was the originator of the thread interested in the kernel >>>> to use the gpu for floating point operations or integer >>>> operations? >>>> If floating point, the x86 (among others) already has an >>>> integrated fpu, and the integer logic is already in the cpu (or alu). >>>> So I do not understand what sort of computations the originator >>>> of the thread would like to see done on the gpu. >>>> >>>> jd >>>> >>>> >>> The other OS's Mac and Windows are using the GPU in its video >>> conversion programs. >>> The newer programs will have selections to activate the GPU for computation. >>> >>> I have been using the GPU for scientific computation for quite a while now. >>> Seti@home is very much a hobby and it takes samples from the areciebo >>> telescope and analyse data looking for "You guessed it, ET" >>> It will crunch numbers very fast compared to a normal CPU. >>> >>> I bench my Phenom 2 965 at 3 gflops/cpu while the GPU will be doing 54 >>> Gflops . >>> >>> I have a slow video card Nvidia 9400GT. The bigger ones will go right up >>> to a full teraflop. >>> That kind of speed would be well accepted if an OS would use it >>> generally or software that is written for Video conversion to use it >>> greatly reducing time. >>> >>> >>> That's what I would like to see, more focus on speeding up video >>> conversion especially with HD video and it seems that the GPU is a very >>> inexpensive way to add a lot of power to your machines >>> >> A teraflop?? WHoa! Can the PCI bus really feed the gpu with >> an instruction stream that will yield that performance? >> > Err, no. GPUs are massively parallel beasts. They can't reach level of > performance via a discrete instruction stream, not to mention even > the PCIe bus couldn't cope with it really. The high performance comes > from the GPU programmes are executed by their hardware threads > in parallel on large amounts of data. > >> I mean most pc's out there are in people's homes still pci (33 or 66 MHz >> bus). >> Relatively, fewer are on pci x16 which is a much faster bus. >> >> Thanks for your feedback. >> >> >> So, given the extreme limitations of the bus relative to the teraflop speed of the gpu, how can the cpu feed the gpu with "data" at a rate that can sustain continuous 1 teraflops/sec? Is there a pci-e32 with a faster bus clock on the horizon? There are so many programs that use/need floating point operations on matrices that could benefit vastly from this. I hope someone(s) can point to such future HW development. -- users mailing list users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines
