[petsc-dev] http://www.hpcwire.com/hpcwire/2012-11-12/intel_brings_manycore_x86_to_market_with_knights_corner.html

[Anton Popov]

On 11/13/12 2:54 AM, Paul Mullowney wrote:
> Every test we've done shows that the MKL triangular solve doesn't 
> scale at all on a sandy bridge multi-core. I doubt it will be any 
> different on the Xeon Phi.
>
> -Paul
Do you mean sparse or dense solves? Sparse triangular solves are 
sequential in MKL. PARDISO also does it sequentially.

Anton

>>>
>>>>
>>>> In terms of raw numbers, $2,649 for 320 GB/sec and 8 GB of memory 
>>>> is quite a lot compared to the $500 of a Radeon HD 7970 GHz Edition 
>>>> at 288 GB/sec and 3 GB memory. My hope is that Xeon Phi can do 
>>>> better than GPUs in kernels requiring frequent global 
>>>> synchronizations, e.g. ILU-substitutions.
>>>
>>>     But, but, but it runs the Intel instruction set, that is clearly 
>>> worth 5+ times the price :-)
>>
>> I'm tempted to say 'yes', but at a second thought I'm not so sure 
>> whether any of us is actually programming in x86 assembly (again)?
>> Part of the GPU/accelerator hype is arguably due to a rediscovery of 
>> programming close to hardware, even though it was/is non-x86. With 
>> Xeon Phi we might now observe some sort of compiler war instead of 
>> low-level kernel tuning - is this what we want?
>>
>> Best regards,
>> Karli
>>
>
>