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

[vega lew]

Dear sir,

You answer is quite helpful to me. Thank you very much. Actully, the speed
of calculation for a large system is more
important for us. So I think the bandwidth is the key issue.

could I recognize the bandwidth you mentioned as the FSB (Front system bus)
of the montherboard and the frequency of memory such as 800MHz or 1066 MHz
and so on?

thank you for your reply

vega

On Wed, Mar 25, 2009 at 8:45 PM, Axel Kohlmeyer <akohlmey at cmm.chem.upenn.edu
> wrote:

> 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
> >
> ******************************************************************************************************************
> > 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
>   Center for Molecular Modeling   --   University of Pennsylvania
> Department of Chemistry, 231 S.34th Street, Philadelphia, PA 19104-6323
> tel: 1-215-898-1582,  fax: 1-215-573-6233,  office-tel: 1-215-898-5425
> =======================================================================
> If you make something idiot-proof, the universe creates a better idiot.
>
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-- 
==================================================================================
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
******************************************************************************************************************
Email: vegalew at gmail.com
Office: Room A705, Technical Innovation Building, Xinmofan Road 5#, Nanjing,
Jiangsu, China
******************************************************************************************************************
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