hi everyone: It's my first time to use QE, and I meet some problems that I don't know how to handle it. *DESCRIPTION* At first, I compile the QE5.0.2 without GPU. And I use pw.x to run my relax.in(attach at the end), using the command: *[PATH_TO_QE]/bin/pw.x -in relax.in <http://relax.in/>* By this version, I can run relax.in to the end. However, when I recompile QE with Nvidia GPU (QE-GPU-r216.tar.gz with the QE-5.0.2_GPU-r216.patch, and I use CUDA5.5), I meet the one of the Frequent errors during execution<http://www.quantum-espresso.org/faq/frequent-errors-during-execution/>, which is *%%%%%%%* * Error in routine electrons (1):* * charge is wrong* * %%%%%%%* So I change the input file by comment some settings on SYSTEM modules. * ! occupations='smearing',smearing='gaussian',degauss=0.002,* * ! nspin=2* And then I can run it on my gpu host, using my gpu card. For this situation, I guess the "*gaussian **smearing" *may lost some precision on GPU calculation. But I'm not sure that.
* QUESTION* I feel confused of this situation. My question is 1, Is the GPU's precision not support for some of the QE workload? or just some algorithms? 2, If it's just for the algorithms problem, which algorithm would be affect during calculating on GPU version? How should I do when I want to use GPU to accelera the QE-CPU version? 3, The last question is, what changes would happen to the final result when I modify the parameter "*occupations" *and* "**smearing**"*? Just like the PW/tests/check-pw.x.j, if I don't have the reference, How can I check whether my result is true when I calculate for the new workload? Thanks for everyone ! Maybe my chinglish would confuse you, but please report it to me. Because I really want you help ! Thank you very much ! -- Tobin Chen Sun Yat-Sen University <http://www.sysu.edu.cn/>, Guangdong, China. *file relax.in <http://relax.in/>* &control calculation = 'vc-relax' prefix='Na2Fe2As2O', pseudo_dir ='/home/jin/projects/asc14/suanli/test2/workload1/workload2-upf' outdir='./tmp' etot_conv_thr = 1.0E-5 , forc_conv_thr = 1.0D-4 tprnfor=.TRUE. disk_io='none' / &system ibrav=7, celldm(1) =7.691188393, celldm(3)=3.756265356, nat=7, ntyp=5, ecutwfc=40, ecutrho=480, occupations='smearing',smearing='gaussian',degauss=0.002, nspin=2 starting_magnetization(2)=0.125 starting_magnetization(3)=-0.125 ! nbnd=35 ! lda_plus_u=.TRUE. ! Hubbard_U(2)=6.0 / &electrons electron_maxstep=300 mixing_beta = 0.3 conv_thr = 1.0d-10 / &ions bfgs_ndim= 3, ion_dynamics='bfgs' pot_extrapolation = 'second_order' , wfc_extrapolation = 'second_order' / &CELL cell_dynamics = 'bfgs' / ATOMIC_SPECIES Na 22.99 Na.pw91-sp-van_ak.UPF Fe1 55.845 Fe.pw91-sp-van_ak.UPF Fe2 55.845 Fe.pw91-sp-van_ak.UPF As 74.92 As.pw91-n-van.UPF O 16.00 O.pw91-van_ak.UPF ATOMIC_POSITIONS {angstrom} Na 0.0000000000 0.0000000000 4.7989032000 Na 0.0000000000 0.0000000000 10.4890968000 Fe1 0.0000000000 -2.0350000000 7.6440000000 Fe2 2.0350000000 0.0000000000 7.6440000000 As 0.0000000000 0.0000000000 1.8529056000 As 0.0000000000 0.0000000000 13.4350944000 O 0.0000000000 0.0000000000 7.6440000000 K_POINTS {automatic} 4 4 4 1 1 1 npool=2 -------------- next part -------------- An HTML attachment was scrubbed... URL: http://pwscf.org/pipermail/pw_forum/attachments/20140221/da7345da/attachment.html