[gmx-users] replica exchange

[David van der Spoel]

X.Periole wrote:

> On Thu, 12 Jan 2006 21:41:28 +0100
>  David van der Spoel <spoel at xray.bmc.uu.se> wrote:
>
>> Andrea C. Vaiana wrote:
>>
>>> We're using mpich-1.2.4 and it does'nt hang with anything from 2 to  
>>> 48 replicas. What I do see is a ~20% difference in performance  
>>> between the 2 and 48 replicas, can anyone explain this? Would it 
>>> just  be sufficient to switch to LAM to get optimal performance?
>>
>> No,
>>
>> this is due to the different density, you will see that at high 
>> temperature fewer inteeractions are calculated.
>>
> should this increase the speed ??


Yes, as long as the PME grid is the same.

-- 
David.
________________________________________________________________________
David van der Spoel, PhD, Assoc. Prof., Molecular Biophysics group,
Dept. of Cell and Molecular Biology, Uppsala University.
Husargatan 3, Box 596,  	75124 Uppsala, Sweden
phone:	46 18 471 4205		fax: 46 18 511 755
spoel at xray.bmc.uu.se	spoel at gromacs.org   http://xray.bmc.uu.se/~spoel
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