[Pw_forum] Convergence threshold

[Sergey Lisenkov]

Dear PWscf authors and users,

I am wondering about one thing. I put the next criteria in my input file:

conv_thr =  1.0d-8

Sometimes the code finish the scf loop after reaching of this criteria, but sometimes it goes next:

total cpu time spent up to now is   5982.74 secs

     total energy              =  -304.04820402 ryd
     estimated scf accuracy    <        5.4E-09 ryd

     iteration #  7     ecut=    38.00 ryd     beta=0.30
     Davidson diagonalization (with overlap)
     ethr =  6.69E-12,  avg # of iterations =  2.3

     total cpu time spent up to now is   6031.30 secs

     End of self-consistent calculation

....
!    total energy              =  -304.04820402 ryd
     estimated scf accuracy    <        5.6E-10 ryd

Is it normal? 

 Best ,
   Sergey