Calculation of ground state with GPU

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OlivierM
Posts: 1
Joined: Mon Jul 30, 2012 5:09 pm

Calculation of ground state with GPU

Post by OlivierM » Thu Aug 02, 2012 9:11 pm

Hello everyone,

I have been using GPU to calculate the ground state and it's been working fine until I seemed to hit some kind of barrier past a certain value of ecut. I have been trying 2 different configurations of atoms and for both when ecut gets larger, past some point I get the CUFFT_EXEC_FAILED error for the backward fourrier transform. For both configurations the only thing I have noticed to be alike was the value of mpw in which at 65795 the run failed, and at 65267 (which correspond to .1 ecut under the value where it failed) the run succeeded.

So far I have tried to force a bigger fft grid, free the memory of the gpu and reallocate everything before the fft, send the fft calculation to another gpu (I am working on a cluster with 8 cards on it), set every points of the fft grid with zeroes, commented every line of the source code except for the backward fourrier transform, and used another cluster with cards with 3-4 times more RAM than the ones I'm usually working on, but I still get the same error at the exact spot for the same values of ecut.

I have activated double-precision (I get the same error with single precision), the GPUs are GeForce GTX 580 with 1.5 gigs of ram and the cuda version used is 4.0.17.

Anyone got this problem before and were able to fix it?

Thank you.

VasiaS
Posts: 11
Joined: Fri Feb 03, 2012 9:15 pm

Re: Calculation of ground state with GPU

Post by VasiaS » Wed Nov 21, 2012 8:16 am

I have the analogical problem with backward fourier transform, but using large acell (~15; even for one molecule H2).
I can program on CUDA C++ but compile my progs only under windows platform (I'm not a Linuxoid :)). I could try to solve the problem with FTT on CUDA (in CuFTT lib). I need the code that uses FTT and doesn't work. So can you send me the code that you didn't comment?

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torrent
Posts: 127
Joined: Fri Aug 14, 2009 7:40 pm

Re: Calculation of ground state with GPU

Post by torrent » Wed Nov 21, 2012 6:46 pm

Hi OlivierM,

First of all, could you give the version number of ABINIT you are using ?...

Several errors occuring in cuFFT have been already corrected (they are not related to FFT but to array overflow before...)
I'm afraid you have to wait for Abinit v7.0 (to be released at the end of this week, in theory).

Marc
Marc Torrent
CEA - Bruyères-le-Chatel
France

VasiaS
Posts: 11
Joined: Fri Feb 03, 2012 9:15 pm

Re: Calculation of ground state with GPU

Post by VasiaS » Sun Nov 25, 2012 5:51 pm

now I use abinit 7.0 . When I do the calculation of platinum, I get the following warning:

ITER STEP NUMBER 1
scfcv : 1
vtorho : nnsclo_now= 2, note that nnsclo,dbl_nnsclo,istep= 0 0 1

cgwf.F90:588:WARNING
New trial energy at line 3 = -6.142106E-01
is higher than former = -6.214122E-01


cgwf.F90:588:WARNING
New trial energy at line 4 = -6.028546E-01
is higher than former = -6.142106E-01

Other problems are not found yet

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