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Re: Re-starting a calculation
Hi again Paula,
Glad to know you found it useful.
Angel
On Tue, 2002-12-03 at 10:19, Paula wrote:
> Dear Angel,
>
> Thank you for your comments, l will certainly try to get and compile the
> chpox utility.
>
> Paula
>
> At 18:07 02/12/02 +0100, you wrote:
> >Hi Paula,
> >
> >There is a small checkpointing utility called chpox that can be
> >downloaded from sourceforge.net. It allows saving the state of any
> >process in a file and restarting it later from that point. In conjuction
> >with a small shell script and cron it is quite powerful. I know that it
> >works well for intel processors. The author claims that it also works
> >with alpha architecture, but I have had problems compiling it. Please,
> >let me know if this helps.
> >
> >Angel,
> >
> >PS, maybe this module could be integrated with FEFF in a future release?
> >
> >
> >On Mon, 2002-12-02 at 17:56, John J. Rehr wrote:
> > > Paula Harkins asked about restarting a FEFF8 calculation:
> > >
> > > >I am using Feff8 (ver 8.1) and wondered if there was any way to restart a
> > > >calculation from the point that it was stopped at rather than having to
> > > >wait for the whole calculation to run again. (I share my computer with
> > > >several other users!) Any ideas?
> > >
> > > At present this can only be done module by module. For example if a
> > > calculation stops during the 3rd module [FMS], it is not necessary to
> > > rerun the first two modules and one can restart the calculation with
> > >
> > > CONTROL 0 0 1 1 1 1
> > >
> > > You can check that a module has finished by looking at the last line
> > > in logn.dat. For example, when the potentials have been calculated the
> > > last line should say:
> > >
> > > Done with module 1: potentials.
> > >
> > > What else can be done?
> > >
> > > If you do want to stop a job temporarily, you can use the ctrl-z command
> > > in unix to stop a job and then restart later with the command fg.
> > >
> > >
> > > Several things can be done to optimize the speed to avoid the need for
> > > stopping/restarting:
> > >
> > > i) For XANES calculations, the time goes up as [N(lmax+1)**2]**3,
> > > so you should keep the cluster size as small as you can get away
> > > with without sacrificing accuracy [typically 30-40 atoms] and
> > > with default lmax [set lmax = -1 in POTENTIALS].
> > >
> > > ii) For the FMS part, if you have FEFF8.2 the calculations go faster
> > with the
> > > Lanczos algorithm.
> > >
> > > We'll look into the possibility of restarting a FEFF8 calculation mid
> > > module. Certainly some band structure codes allow one to restart during
> > > the SCF loop.
> > >
> > > Cheers,
> > > John Rehr
> > >
> > >
> > >
> > >
>
>