Hi Marcos,

The compiler was gcc 4.3.4
The mpi was openmpi 1.3.3 for the gcc compiler and 64 bits
Flags were:
FFLAGS=-g -O2
FPPFLAGS= -DMPI -DFC_HAVE_FLUSH -DFC_HAVE_ABORT -DCDF

we had to add an additional flag
INCFLAGS=-I/cm/shared/apps/netcdf/gcc/64/4.0.1/include/
because for some reasons the compiler could not find by itself the netcdf
location

The arch.make file is attached

Thanks!
Ludo

(See attached file: arch.make)

Marcos Veríssimo Alves <[email protected]> wrote on
07/09/2010 10:40:57:

> Hi Ludovic,
> This is in principle weird. The # of steps for SCF convergence
> should not depend on the blocksize. Could you provide some info on
> your compilation? Compiler, optimization flags, mpi and compilation
> flags for mpi compilation?
> Marcos
> El 7 de sep de 2010, 10:23 a.m., "Ludovic Briquet" <[email protected]
> > escribió:

> Dear SIESTA users,
>
> I am in process of assessing how well the parallel version of SIESTA
> 2.0.2 performs on our new cluster. To do so, I'm runing test jobs
> and monitoring the timing of the jobs with different SIESTA and
> cluster-related inputs.
> The test job I'm running is a (1x2) Si(100) slab geometry
> optimisation. The system contains 64 atoms. Functional is PBE, mesh
> cutoff is 150 Ry, Kpoint mesh is 4x2x1. The basis set is setted as
>
> %Block PAO.Basis
> Si 3 -0.46385
> n=3 0 2 E 15.42551 4.96988
> 7.00000 4.37722
> 1.00000 1.00000
> n=3 1 2 E 4.69636 3.83128
> 7.00000 4.09123
> 1.00000 1.00000
> n=3 2 1 E 11.96912 0.03131
> 4.55426
> 1.00000
> %EndBlock PAO.Basis
>
> 1- When I don't specify any BlockSize, SIESTA use a defautl value of
> 24 and not 8 as stated in the user guide. Does anyone know the
> reason for that?
>
> 2- When trying different BlockSize options, I see that the scf
> convergence is not the same for all jobs.
>
> For exemple, for a 4 cpu job:
> BlockSize 8: total run time is 15h54 - first optimization step is
> completed with 205 scf iterations
> BlockSize 16: total run 16h22 - - first optimization step is
> completed with 222 scf iterations
> BlockSize 24: total run 13h15 - first optimization step is completed
> with 74 scf iterations
> BlockSize 32: total run 19h09 - first optimization step is completed
> with 399 scf iterations
> It should be noted that the energies at the end of the scf processes
> are all similar and the optimisation terminates in 34 steps for all jobs.

>
> I understood from the tutorial session in Santander last June that
> the compilation of SIESTA in parallel can be a very tricky business.
> So I was wandering if that scf behviour could in anyway be related
> to the compilation? Or is it just a normal behaviour of SIESTA?
>
>
> Cheers
> Ludovic

Attachment: arch.make
Description: Binary data

Responder a