[Pw_forum] about output wavefunction, charge density and potential

[Paolo Giannozzi]

On Tuesday 04 April 2006 09:56, J G Che wrote:

> However, now there are many abinit packages based plane-waves
> which don't use disk but RAM to store wavefunctions, meaning it
> could be at least as a option. Otherwise, such an often writing on 
> disk not only wastes too much time, but also leads to NFS crashing

one should never use NFS-mounted filesystem for I/O. Use locally
mounted scratch disks, or a parallel file system (GPFS) if you have one.

Also note that modern operating system tend to keep data in memory
as long as possible. Data to disk is actually written when no more RAM
for caching is available.

Anyway: I agree that it is useful in many cases to keep everything 
in memory, but this requires some work

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