[Pw_forum] insufficient virtual memory

[Lorenzo Paulatto]

In data 19 agosto 2009 alle ore 15:15:55, Raji Abdulrafiu  
<tunderaji at gmail.com> ha scritto:
> Despite all these steps, the error persists, and
> I am just not sure of what to do again. I need help please!. I am
> using ver.4.0 of QE, and the calculation is being done using the
> CINECA parallel computers.

Dear Raji,
the memory usage of projwfc.x only depends on the wfc cutoff, all the  
other chages were probably irrelevant.

The code loads the wavefunctions for all bands from one k point at a time,  
and for all atomic wavefunctions at the same time. The amount of required  
memory can increase fast with the number of atoms and with the number of  
bands. Furthermore that code is not parallelized (at the moment), this  
could cause some problem.

I would advice you to request an entire node (4 processors) for the  
calculation and than only use one processor, in this way you'll have 8GB  
of RAM all for yourself. If it still does not work, please ask again  
providing more detail about your system, and *important* the version of QE  
you are using.

best regards


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Lorenzo Paulatto
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