[Pw_forum] Do you think Intel I7 series could improve the parallel efficiency

[Axel Kohlmeyer]

On Wed, 2009-03-25 at 19:30 +0800, vega lew wrote:
> Dear all,
> 
> Is there someone perform QE on intel I7 platform? Do you think
> parallelzation QE could benefit from the QPI technology of intel I7
> series very much?

the integrated memory controller and parallelization have very
little connection directly. please don't "believe" in buzzwords.

what _will_ help codes like Q-E in general is the greatly enhanced
memory bandwidth, particularly the for larger systems. for smaller 
systems that mostly fit into the cache, the gains will be much smaller.
the floating point unit of those cpus is essentially the same as in
the current xeon processors.
since the various tests posted on the list here demonstrated that 
(some of) Q-E's parallelization schemes are very much affected by
insufficient memory bandwidth, there will be a gain. however, those 
CPUs will also have a different cache architecture, which may in 
turn chew up some of the benefits, particularly for smaller problems.

cheers,
   axel.



> 
> vega
> 
> -- 
> ==================================================================================
> Vega Lew ( weijia liu)
> PH.D Candidate in Chemical Engineering
> State Key Laboratory of Materials-oriented Chemical Engineering
> College of Chemistry and Chemical Engineering
> Nanjing University of Technology, 210009, Nanjing, Jiangsu, China
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> Email: vegalew at gmail.com
> Office: Room A705, Technical Innovation Building, Xinmofan Road 5#,
> Nanjing, Jiangsu, China  
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Axel Kohlmeyer   akohlmey at cmm.chem.upenn.edu   http://www.cmm.upenn.edu
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