time step error reported by Dr. Seiji Tsuboi from JAMSTEC in Japan

[komatits]

Time step error reported by Dr. Seiji Tsuboi from JAMSTEC in Japan: (the time step value automatically computed by the code for that case seems wrong?)

"I have used specfem3d_globe-7.0.0 on intel
cluster and have
overflow problems.
If I set NPROC=16 and NEX=768 (1536 cores), I
could
calculate
seismograms correctly. However if I increase
NEX, for
example
NPROC=17, NEX=816 (1734 cores), xspecfem3D
stops with
overflow
in the very beginning of computation.
ATTENUATION is
set as true
and it seems that the program overflows in
"multiply_accel_elastic" routine. I tried both
ifort and
gfortran but the situation is the same. I would be
grateful if
someone would let me know how I should solve
this issue. "

My answer:

" Thank you very much for your answer.
To change the value of the time step DT automatically
computed by
the code, you can edit file
src/shared/get_timestep_and_layers.f90
and put something like:

         DT = DT * 0.90

         at the end of that routine. This should fix the problem."

but this does not fix the problem:

"I have added
DT=DT*0.90
at the end of src/shared/get_timestep_and_layers.f90 but it
overflowed I also have tried 0.8 instead of 0.9 but the
situation seems to be the same. I have checked in
output_solver.txt that DT is properly reduced.

    Best regards,
    Seiji Tsuboi."