[Pw_forum] about one "fatal error"

[L.F.Huang]

Hello everyone:
  I am calculating graphene supercell with one vacancy impurity, whose size
is 4*4*1. It is an magnetic system whose magnetization is 0.8 bohr magneton.
And there are 31 atoms and 93 representations with one mode for each. At
first, ph.x is executing well, however, when the 23th representation is being
done, there comes out some strange thing:
**********************************************************************
FATAL ERROR on MPI node 3 (ganode054): GM send to MPI node 10 (???
[00:60:dd:49:08:2a]) failed: status 18 (target node was unreachable) check
the target host, mapping or cables
Small/Ctrl message completion error!
forrtl: error (76): IOT trap signal
FATAL ERROR on MPI node 9 (ganode057): GM send to MPI node 10 (???
[00:60:dd:49:08:2a]) failed: status 18 (target node was unreachable) check
the target host, mapping or cables
Small/Ctrl message completion error!
forrtl: error (76): IOT trap signal
**********************************************************************
AND:
PWSCF version: QE3.2.3
K_point grid: 10*10*1 with 52*2(the 2 is due to magneticity) reduced k_points
Number of nodes: -np 8

Does anyone knows what is the reason of this error? and How can I do to
solve it?
I would like appreciate any advice very much!!!

Yours Sincerely
Huang

======================================================================
L.F.Huang(黄良锋) lfhuang at theory.issp.ac.cn
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      Instutue of Solid State Physics,the Chinese Academy of Sciences,
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