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Restart q-point interpolation
Posted: Wed Oct 25, 2017 8:10 pm
by gbrunin
Hi everyone,
I am using restart = .true. and restart_freq = 500 for a calculation. The file XXX.sigma_restart1 is well written, and I have the line
in my output file. My problem is that the interpolation seems to begin from the start again. It starts at iq = 1 and the calculation is now at iq = 395, thus higher than the 375 q-points remaining from the previous run. Here is my input file :
Code: Select all
EPW computation for Ca2N
&inputepw
prefix = 'Ca2N'
dvscf_dir = '../ph/save/'
amass(1) = 40.078
amass(2) = 14.007
outdir = '/scratch/ucl/naps/gbrunin/epw/'
max_memlt = 4
!epbwrite = .true.
!epbread = .false.
epbwrite = .false.
epbread = .true.
epwwrite = .true.
epwread = .false.
kmaps = .false
elph = .true.
etf_mem = .false.
nbndsub = 4
nbndskip = 1
dis_froz_min = -0.45
dis_froz_max = 3.92
dis_win_min = -0.5
dis_win_max = 3.92
proj(1) = 'N:px;py;pz'
proj(2) = 'f=0.5,0.5,0.5:s'
!wannierize = .true.
wannierize = .false.
num_iter = 1000
iprint = 2
iverbosity = 0
elecselfen = .true.
phonselfen = .true.
a2f = .true.
parallel_k = .true.
parallel_q = .false.
fsthick = 1 ! eV
eptemp = 300 ! K
degaussw = 0.025 ! eV
degaussq = 0.05 ! meV
filukk = './Ca2N.ukk'
!rand_nk = 20000
!rand_nq = 80000
!rand_q = .true.
!rand_k = .true.
nkf1 = 70
nkf2 = 70
nkf3 = 70
restart = .true.
restart_freq = 500
nqf1 = 15
nqf2 = 15
nqf3 = 15
nk1 = 24
nk2 = 24
nk3 = 24
nq1 = 8
nq2 = 8
nq3 = 8
/
65 cartesian
...
Am I missing something ?
Thanks in advance
Re: Restart q-point interpolation
Posted: Thu Oct 26, 2017 10:12 am
by sponce
Hello Guillaume,
Indeed you are not doing a restart run. In addition to restart = .true. you also need:
Code: Select all
epbwrite = .false.
epbread = .false.
epwwrite = .false.
epwread = .true.
kmaps = .true.
elph = .true.
etf_mem = .false.
By the way, you should use the most recent version of the code.
In that case:
Best,
Samuel
Re: Restart q-point interpolation
Posted: Thu Oct 26, 2017 2:31 pm
by gbrunin
Hi Samuel,
Thanks for your answer. I did as you suggested but I still have the same problem. I have now
Code: Select all
------------------------------------------------------------------------
RESTART - RESTART - RESTART - RESTART
Restart is done without reading PWSCF save file.
Be aware that some consistency checks are therefore not done.
------------------------------------------------------------------------
at the beginning of my output file but the q-point interpolation starts at the first q-point, even if there is the message to say that it restart from another one.
Thanks for your suggestions,
Guillaume
Re: Restart q-point interpolation
Posted: Thu Oct 26, 2017 4:33 pm
by sponce
Hello,
Its an information message. It's normal.
Are you sure that your XXX.sigma_restart1 is correct ?
You might have re-written on it since before you restarted incorrectly and start from the beginning. You said you were at 395 q which is less than 500 and therefore nothing
has been written to the restart file yet so if you restart it will restart from 1.
You can do a test by lowering restart_freq = 10 for example and then crash the code after 11 q-points. Then restart. It should restart from 10.
Best,
Samuel
Re: Restart q-point interpolation
Posted: Thu Oct 26, 2017 5:08 pm
by gbrunin
Hi,
Yes, I thought I could have problems with that run because of that. I have two jobs that I want to restart, and I had not done anything on the second one yet. So I will explain with more details what I did for this one because it is cleaner.
First, I did a job for fine q-point and k-point grids of 20x20x20 (I know it's not enough) with the same input file as in my first post (except for the grids). The interpolation went up to the 7700 q-point out of 8000, and each 500 q-point a message was written that the restart point was created.
Then, I changed my input file as you said, and the restart calculation started at iq = 1 instead of 7501 as I expected.
I hope it is more clear now. I can do a test run but I think it will give me the same result.
Thanks,
Guillaume
Re: Restart q-point interpolation
Posted: Fri Oct 27, 2017 9:47 am
by sponce
Hello Guillaume,
Can you try the following input :
Code: Select all
EPW computation for Ca2N
&inputepw
prefix = 'Ca2N'
dvscf_dir = '../ph/save/'
amass(1) = 40.078
amass(2) = 14.007
outdir = './'
epbwrite = .false.
epbread = .false.
epwwrite = .false.
epwread = .true.
kmaps = .true.
elph = .true.
etf_mem = .false.
nbndsub = 4
nbndskip = 1
dis_froz_min = -0.45
dis_froz_max = 3.92
dis_win_min = -0.5
dis_win_max = 3.92
proj(1) = 'N:px;py;pz'
proj(2) = 'f=0.5,0.5,0.5:s'
wannierize = .false.
elecselfen = .true.
phonselfen = .false.
a2f = .false.
parallel_k = .true.
parallel_q = .false.
fsthick = 3 ! eV
eptemp = 300 ! K
degaussw = 0.025 ! eV
nkf1 = 24
nkf2 = 24
nkf3 = 24
restart = .true.
restart_freq = 50
nqf1 = 8
nqf2 = 8
nqf3 = 8
nk1 = 24
nk2 = 24
nk3 = 24
nq1 = 8
nq2 = 8
nq3 = 8
/
65 cartesian
...
Manually crash the calculation just after the first 50 q-points have been written.
PS: Are you sure you need 24x24x24 k-grid for the fine grid ? This seems super dense. 16x16x16 should be already a lot.
Best,
Samuel
Re: Restart q-point interpolation
Posted: Fri Oct 27, 2017 12:47 pm
by gbrunin
Hi Samuel,
Here is what it gives me.
Code: Select all
Restart from: 11/ 3375
===================================================================
Electron (Imaginary) Self-Energy in the Migdal Approximation
===================================================================
Fermi Surface thickness = 1.000000 eV
Golden Rule strictly enforced with T = 0.025852 eV
Gaussian Broadening: 0.025000 eV, ngauss= 1
DOS = 0.522114 states/spin/eV/Unit Cell at Ef= 2.909832 eV
Creation of a restart point
Creation of a restart point
It does not print any information about the q-point interpolation in the output file, just when a restart point is created. I tried this input 3 times : the first time, I had only one "Creation of a restart point" message. The second time, it said that it started again from q-point 11 (I set restart_freq = 10), and created 2 restart points (see output above). Then the third time, it started again from q-point 21, but I guess it should have started from 31 if the restart point was working in the previous runs.
About the coarse k-point grid, will the computation be longer if it is denser ? Or "just" use more memory ?
Thanks for your help !
Guillaume
Re: Restart q-point interpolation
Posted: Fri Oct 27, 2017 4:38 pm
by sponce
Hello,
I think it works as intended.
1) The printing information is hardcoded in EPW to be every 50 q-points (you can off course change that). This is the reason why you do not see the q-point information yet.
2) The reason why it restarted from 21 is because the first "creation of a restart point" is actually the re-writing to file of the first 10 q-points. So in practice you only go to 20 q-points.
3) yes it should be faster and less memory.
Best,
Samuel
Re: Restart q-point interpolation
Posted: Mon Oct 30, 2017 9:07 am
by gbrunin
Hi again,
I tried a little bit longer runs to be sure if it was working or not. I have the message (restart_freq = 50)
and then
Code: Select all
Creation of a restart point
Progression iq (fine) = 100/ 3375
Creation of a restart point
Creation of a restart point
So I don't really understand if the job restarted properly or not.
Thanks,
Guillaume
Re: Restart q-point interpolation
Posted: Mon Oct 30, 2017 3:01 pm
by sponce
Hello,
Ok that is indeed wrong.
Could you install the current development version of Quantum Espresso that includes EPW and try again:
https://github.com/QEF/q-eYou can do
git clone
https://github.com/QEF/q-e.gitTo get the latest version.
Sorry for the problems,
Best,
Samuel