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GPAW Convergence Behavior

A talk given by Ansgar Schaefer studying convergence behaviour for rutiles is here (pdf).

General suggestions for helping GPAW convergence are here.

A discussion and suggestions for converging some simple systems can be found here.

Other convergence experience:

System	Who	Action
Graphene with vacancy	Felix/JensH	Increase Fermi Temp from 0.1 to 0.2, use cg
Graphene with vacancy	cpo	change nbands from -10 to -20, MixerDif(beta=0.03, nmaxold=5, weight=50.0)
Nitrogenase FeVCo for CO2 reduction	grabow	use Davidson solver (faster as well?), although later jvarley said MixerSum
Several surfaces	aap	Broyden mixer with Beta=0.5

GPAW Memory Estimation

The get a guess for the right number of nodes to run on for GPAW, run the
following line interactively:

gpaw-python <yourjob>.py --dry-run=<numberofnodes>
(e.g. gpaw-python graphene.py --dry-run=16)

Number of nodes should be a multiple of 8. This will run quickly
(because it doesn't do the calculation). Then check that the
following number is <3GB for the 8-core farm, <4GB for the 12-core farm:

Memory estimate
---------------
Calculator  574.32 MiB

Building a Private Version of GPAW

Use svn to check out the version of GPAW that you want to use
copy /afs/slac/g/suncat/bin/privgpaw.csh into whatever directory you like
edit the two variables GPAW_BASE ("base" GPAW release that you want to re-use for numpy, mpi etc.) and GPAW_HOME (directory where you checked out GPAW)

Use the commands:

privgpaw.csh build
privgpaw.csh test
privgpaw.csh bsub <arguments>

Some notes:

You can see a list of available installed versions here (to use for GPAW_BASE).
The syntax for the "bsub" option is identical to the gpaw-bsub command described here.
The above assumes that the base release is compatible with your checked out GPAW version. Talk to cpo if you have questions about this.
The above doesn't include support for a private version of ASE. When that becomes important we will add it.

Jacapo Parallel NEB Example

You can find a Jacapo parallel NEB example in /afs/slac/g/suncat/example/parneb.py. Some lines need to change for a restart. An example is in the same directory in parneb_restart.py.

Note that this restart example turns on the "FIRE" and and "climb" parameters: this is for later in the calculation. The documentation here discusses the reasons for that (although perhaps doesn't spell out clearly what the criteria are for turning those on).