Very useful information. Grazie Paolo, G
>----Messaggio originale---- >Da: giannozz at democritos.it >Data: 07/02/2012 10.57 >A: "giacsport at libero.it"<giacsport at libero.it> >Cc: <pw_forum at pwscf.org> >Ogg: Re: [Pw_forum] scalability of the code > >On Tue, 2012-02-07 at 09:38 +0100, giacsport at libero.it wrote: > >> I would like to know which is the highest number of processors >> used and reported for running PWscf code. > >I have seen a test run on 65536 processors (cores, I mean). >Unfortunately I do not find any longer a test on a 8000-atom >system recently done: I guess it was also run on more than >just a few processors. > >> Are there data or reports on the scalability of the code (well) >> above 1000 processors? > >there is something in the Benchmark section of the new web site >( http://testwp.qe-forge.it/wordpress-3.1.4/?page_id=44 ). >More data will (maybe) come (subject to my allergy to both benchmarks >and wordpress, and to everybody's allergy to documentation) > >> We are indeed interested in installing the code in a massively parallel >> machine, but before doing it we would like to have more information. > >QE has been installed (with little effort) on several BlueGene machines. >It works (i.e. it has ben used for real scientific purposes and has >produced published results in at least one case I am aware of). You >have to be careful with I/O, which can become easily a limiting factor. >You may need to use all available parallelization levels, in particular >OpenMP, to satisfy the machine owners who, for sure, wants you to run >on a number of cores vastly exceeding what you actually need > >P. >-- >Paolo Giannozzi, IOM-Democritos and University of Udine, Italy > > >
