The ABINIT Users Mailing List ( CLOSED )

["Anglade Pierre-Matthieu" <anglade@gmail.com>]

Hi,

For most calculations Abinit memory estimate is accurate. This means that you do not need more memory than the estimated amount. More over when estimating memory requirement Abinit already takes the estimated amount of memory; hereby making sure that the system  can allocate this amount of memory to Abinit.

For Abinit calculation you (likely) wont need more memory than that. However your system stays on with all other processes and your kernel and so on. So you obviously need at least a few more megabytes. And yes they can be virtual as long as you do not expect your system to be reactive during your calculation.

Notice that it is always better to avoid using virtual memory. Therefor you can use input variable like "mkmem" that allows ordered storage of information on your hardrive to reduce memory consumption.

regards

PMA

On 8/17/07, Yu Chol Jun <yucj@ghi.rwth-aachen.de> wrote:

Dear all,

I want to confirm how to estimate the total storage necessary for the
calculation. I thought we can see it from .out file.

Symmetries : space group P1 (#  1); Bravais aP (primitive triclinic)
================================================================================
  Values of the parameters that define the memory need of the present run
    intxc =         0  ionmov =         2    iscf =        17     ixc =
       15
   lmnmax =         8   lnmax =         4   mband =       479  mffmem =
         1
P  mgfft =       150   mkmem =         1 mpssoang=         2     mpw =
    15895
   mqgrid =      3001   natom =       276    nfft =    540000    nkpt =
         1
   nloalg =         4  nspden =         1 nspinor =         1  nsppol =
         1
     nsym =         1  n1xccc =         1  ntypat =         2  occopt =
         1
  PAW method is used; the additional fine FFT grid is defined by:
    mgfftf=       216    nfftf =   1749600
================================================================================
P This job should need less than                     887.891 Mbytes of
memory.
   Rough estimation (10% accuracy) of disk space for files :
   WF disk file :    116.178 Mbytes ; DEN or POT disk file :     13.350
Mbytes.
================================================================================

In this out file, the total memory is 887.891 MB, this means when I
perform this job, I need only 887.891 MB. Now I am wondering if I need
more virtual memory.

Best regards,

Yu.

-- 
Pierre-Matthieu Anglade