[Pw_forum] Error encountered while attempting to allocate a data object.

Paolo Giannozzi giannozz at nest.sns.it
Thu Jan 29 10:53:16 CET 2004

On Thursday 29 January 2004 00:01, Konstantin Kudin wrote:

>  It looks like the amount of memory for "diag:" got
> wrapped around the 32-bit limit and became negative.

that's strange: the amount of memory used is stored in real
numbers, to avoid this kind of problem. Maybe your version
was still using integer numbers.

> Is there a way to reduce the memory required for a
> given PWSCF job?

from the manual:
-----------------------------------------------------------
\item increase the amount of memory you are authorized to use,
\item reduce {\tt nbnd} to the strict minimum
\item use conjugate-gradient or DIIS diagonalization
({\tt diagonalization='cg'} or {\tt 'diis'}):
slower but requires less memory.
\item in parallel execution, use more processors, or use the
same number of processors with less pools.
Remember that parallelization with respect to k-points (pools)
does not distribute memory: parallelization with respect to
{\bf R}-- and {\bf G}--space does.
\item IBM only: if you need more than 256 Mb you must specify it
at link time (option {\tt -bmaxdata}).
-----------------------------------------------------------
The second and third items are relevant to your case

> Or should I just move to a 64-bit machine with enough physical RAM
> such as an SGI?

or to a parallel machine

Paolo

--
Paolo Giannozzi             e-mail:  giannozz at nest.sns.it
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