[Pw_forum] Use of pool

[Axel Kohlmeyer]

On Tue, 24 Feb 2009, Huiqun Zhou wrote:

ZH> Dear list users:
ZH> 
ZH> I happened to test duration times of calculating the system I'm 
ZH> investigating against number of pools used. There are totally
ZH> 36 k points. But the results surprised me quite a lot. 
ZH> 
ZH> no pool:  6m21.02s CPU time,     6m45.88s wall time
ZH> 2 pools:  7m19.39s CPU time,     7m38.99s wall time
ZH> 4 pools: 11m59.09s CPU time,    12m14.66s wall time
ZH> 8 pools: 21m28.77s CPU time,    21m38.71s wall time

dear huiqun zhou,

please note that benchmark numbers are useless without
offering a way to reproduce them. so please provide the
the input used for this test.

also, this looks almost like you are running multiple
copies of a serial binary. please check the top of the
pw.x (you _are_ pw.x, right?) output and check whether
there are the to be expected differences. 

finally, how does the job scale with just one pool?

ZH> 
ZH> The machine I'm using is an AMD box with 2 quad core shanghai.
ZH> 
ZH> Is my understanding of usage of pool wrong?

impossible to tell.

cheers,
   axel.


ZH> 
ZH> Huiqun Zhou
ZH> @Nanjing University, China
ZH> _______________________________________________
ZH> Pw_forum mailing list
ZH> Pw_forum at pwscf.org
ZH> http://www.democritos.it/mailman/listinfo/pw_forum
ZH> 

-- 
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Axel Kohlmeyer   akohlmey at cmm.chem.upenn.edu   http://www.cmm.upenn.edu
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