[gmx-developers] DD support in ASPC

[David van der Spoel]

On 2012-03-06 11:22, Tomáš Trnka wrote:
> Dne Út 6. března 2012 11:08:08, Berk Hess napsal(a):
>> Hi,
>>
>> Keeping track of history is tedious, both for domain decomposition and
>> check pointing.
>>
>> I assume the method should actually not be history dependent and this is
>> only for efficiency?
>
> Well, that depends on the point of view. The whole point of ASPC is to
> dramatically speed up SCF calculations by predicting the induced dipoles based
> on their history. So the ASPC method is history dependent in this sense.
>
> Currently the predictor history is not saved anywhere on disk so the first
> several (1-3) integration steps are significantly slower and have worse energy
> conservation. Saving the history would get rid of this but IMHO it's no big
> deal.
>
> Tomáš
I guess the history must be built up at the beginning of the run.

So how about resetting the history for each particle if it moves to 
another processor, but storing it otherwise?

That will lose some performance obviously.



-- 
David van der Spoel, Ph.D., Professor of Biology
Dept. of Cell & Molec. Biol., Uppsala University.
Box 596, 75124 Uppsala, Sweden. Phone:	+46184714205.
spoel at xray.bmc.uu.se    http://folding.bmc.uu.se