[Pw_forum] I/O problem in phonon and electron-phonon coupling calculations

[Paolo Giannozzi]

On Thursday 16 March 2006 12:21, yanmingma at sohu.com wrote:

> [...] in the phonon and electron-phonon coupling calculations, the
> calculation speed was slowed down dramatically due to the writing 
> process of the temporary files in the hard disk
> [...] my question is that could we use more memory instead of writing
> process in the hard disk? if so, how can we do this.

it can be done but it is not straightforward, at least for the phonon 
calculation: one has to modify the code. It should be done and it
will be done sooner or later, but in the meantime the only solution
is to use the fastest disk you can. In particular, heavy I/O via the 
network to NFS-mounted disks must ABSOLUTELY be avoided.

Paolo
-- 
Paolo Giannozzi             e-mail:  giannozz at nest.sns.it
Scuola Normale Superiore    Phone:   +39/050-509876, Fax:-563513 
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