[Pw_forum] read_file: problem reading .save files

[Konstantin Kudin]

--- Paolo Giannozzi <giannozz at nest.sns.it> wrote:

> On Friday 12 May 2006 14:09, Gabriele Sclauzero wrote:
> 
> >      from read_file  : error #         1
> >      problem reading file /local_scratch/sclauzer/tmp/prefix.save 

> I am quite sure this has been fixed in the meantime.

 Actually, I encountered the same issue too with one of the very recent
CVS versions (2 days ago). While PW itself proceeds fine from the
distributed *.wfc files, the post-processing codes crash (pw2wannier90
for me). I tracked it a bit to the subroutine read_file.f90, where
things crash in these calls
  CALL pw_readfile( 'reset', ierr ) 
  CALL pw_readfile( 'dim',   ierr ) 
even when the *.save directory itself is perfectly visible. Like when
running on 2 cpus of a dual box. I ran under x86-64 Linux with mpich
1.2.7 and ifort 9.0


> Note that
> 
> - there is no guarantee that the processor reading the data file is 
> the same that wrote it in a previous run. One has no control on
> which processor holds which MPI process.

 Some queueing systems read the cpu list from a node file (
$PBS_NODEFILE under PBS ), and so the chance that the order is the same
is high.

> - you need to set wf_collect to .true. in order to save wavefunctions
> into a single file

 But then is post-processing smart enough to read the collected file
and distribute it? I could not verify this due to crashes.

> - if I remember correctly, pseudopotentials are still read by every
> processor. There is no special reason for this, other than the time 
> and boredom needed to implement it in the same way as the rest 
> of I/O (i.e. read on one processor, broadcast all variables to all
> other processors)

 But these come from a separate pseudo-directory, do they not?

 Kostya

__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around 
http://mail.yahoo.com