[Pw_forum] Re: Woodcrest vs Opteron performance in pwscf calc.

[Alexander Shaposhnikov]

Thanks for the answer. 
I don't think this topic is relevant to the PW_forum goals. 

Could you send me the job's input file ? I'd like to test this and
compare with my own Opteron system. We have several Opteron machines,
and if the performance difference is really that big, probably its the
time to move on to the new platform. But my experience with the prev.
generation of Intel processors showed, that Opteron is faster is most
cases, especially then it comes to multi-threaded calculations.

Best Regards,
A. Shaposhnikov


On Wed, 2006-08-02 at 18:09 +0800, Huiqun Zhou wrote:
> Hi, Alexander,
> 
> A short answer is: Woodcrest (2.66 GHz) > Dempsey (3.2 GHz) > Opteron 280 
> (2.6 GHz).
> 
> The compute nodes with woodcrest and dempsey in my cluster have 4GB memory, 
> one SATA
> disk. The nodes with opteron 280 are SUN Fire x4100, each has 8GB memory and 
> two SAS
> disks.
> 
> The test case is total energy calculation of MgAl2O4 (calcium ferrite 
> structure). The system has
> 28 atoms (orthohombic system, Z=4). It took the same number of iterations to 
> reach SCF
> convergency on the 3 different machines and got physically same results. The 
> number in
> parantheses is the elapsed time given by PWscf.
> 
> Here are numbers
> (1) woodcrest (2.66 GHz):
> 1 core : 3m57s (3m55.86s)
> 2 cores: 2m11s (2m10.44s)
> 4 cores: 1m23s (1m17.73s)
> 
> (2) dempsey (3.2 GHz)
> 1 core : (6m26.90s)
> 2 cores: (3m16.47s)
> 4 cores: (1m39.74s)
> 
> (3) opteron 280 (2.6 GHz)
> 1 core : 7m13s (7m09.71s)
> 2 cores: 3m56s (3m52.70s)
> 4 cores: 2m26s (2m16.72s)
> 
> It seems that woodcrest and dempsey are much faster than opteron. The 
> scalability of
> dempsey is the best, woodcrest is the worst. Despite of the amazing 
> performance per
> core of woodcrest, it drops to the same level of its predecessor, dempsey, 
> when taking
> the machine as a unit to evaluate its performance.
> 
> But remember one thing: the number for opteron may not be fair. I compiled 
> the program
> using Intel fortran, Intel MPI 2.0. However, I ever used both Intel and 
> PathScale to
> compile FFTW and its test cases on opteron machine, I didn't find any 
> impressive
> differences.
> 
> Hope it help you.
> 
> 
> Huiqun Zhou
> 
> 
> ----- Original Message ----- 
> From: "Alexander Shaposhnikov" <shaposh at isp.nsc.ru>
> To: "Huiqun Zhou" <hqzhou at nju.edu.cn>
> Sent: Wednesday, August 02, 2006 2:57 PM
> Subject: Woodcrest vs Opteron performance in pwscf calc.
> 
> 
> > Hello dear sir,
> >
> > i have noticed from your posts to PW_forum that you
> > have access to both newest Intel Woodcrest platform and
> > AMD Opteron. Could you compare the performance of these two
> > platforms, for single-threaded, and parallel 4-core pwscf calculations?
> >
> > Thank you in advance,
> > Best Regards,
> > A. Shaposhnikov
> >
> >
> >
> > 
> 
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