[Pw_forum] pwscf 'Relax' problem

[Konrad Gruszka]

Dear Community,

I'm new in QE. I'm using the 5.1.1 version on linux platform.
While trying to do the relax computation, I'm experiencing the following 
problem:

   Error in routine bfgs (1):
       step_old is NOT normalized

(this is not from the start, it appears after some time, e.g. after 3 
hours)

then a little later (couple minutes), I've get about 50 lines similar 
like those below:

      c_bands:  2 eigenvalues not converged
      c_bands:  2 eigenvalues not converged
      c_bands:  2 eigenvalues not converged
      c_bands:  2 eigenvalues not converged
      c_bands:  2 eigenvalues not converged
      c_bands:  1 eigenvalues not converged
      c_bands:  1 eigenvalues not converged
      c_bands:  1 eigenvalues not converged
      c_bands:  1 eigenvalues not converged

and at the same time in console:

darnok at darkstar:~/qe/espresso-5.1.1/moje/YFe5$ mpirun -np 8 pw.x -in 
yfe5.geopt.in -npool 1 > yfe5.geopt.out
application called MPI_Abort(MPI_COMM_WORLD, 1) - process 0
application called MPI_Abort(MPI_COMM_WORLD, 1) - process 0
application called MPI_Abort(MPI_COMM_WORLD, 1) - process 0
application called MPI_Abort(MPI_COMM_WORLD, 1) - process 0
application called MPI_Abort(MPI_COMM_WORLD, 1) - process 0
application called MPI_Abort(MPI_COMM_WORLD, 1) - process 0
application called MPI_Abort(MPI_COMM_WORLD, 1) - process 0

Then only one process (out of 8) remains and continues to run. My 
questions are:
1. If this computation will terminate normally at the end, can I trust 
the results?
2. How to solve this problem?
3. For relax calculations I've read that the K_points section probably 
should be more like 1 1 1 0 0 0 (but why?)
4. Any other tips to speed up the calculations of below physical problem?

This is my input file:

  &control
     prefix='YFe5',
     restart_mode='from_scratch'
     calculation='relax'
     pseudo_dir='/home/darnok/qe/espresso-5.1.1/pseudo/'
     outdir = '/home/darnok/qe/espresso-5.1.1/tempdir/'
  /
  &system
     ibrav=  4, celldm(1) =9.505, nat=  6, ntyp= 2, celldm(3)= 0.77,
     ecutwfc = 80.0, smearing = 'gaussian', occupations = "smearing", 
degauss=0.02,
  /
  &electrons
  mixing_mode = 'plain'
  mixing_beta = 0.7
  /

  &ions
  /

ATOMIC_SPECIES
  Fe  55.845  Fe.pbe-mt_fhi.UPF
  Y  88.906  Y.pbe-mt_fhi.UPF

ATOMIC_POSITIONS {crystal}
  Y 0.00 0.00 0.00
  Fe 0.33 0.66 0.00
  Fe 0.66 0.33 0.50
  Fe 0.50 0.00 0.50
  Fe 0.00 0.50 0.50
  Fe 0.50 0.50 0.50
K_POINTS {automatic}
    9 9 9 0 0 0

Thanks in advance
Konrad Gruszka