[CIG-MC] Benchmark of convection codes including CPU timing and scaling

[John Hernlund]

Hi Shijie,

I think this is a good thing to do, since,

1) there is a lot of discussion about the speed of various codes, but  
no comprehensive quantitative comparisons have been performed to my  
knowledge,

2) solver efficiency is an important benchmark of progress in mantle  
convection-related computing and code development and is one of our  
most important computational issues in general, and,

3) if we can sort out which solution approaches work best (e.g.,  
treatment of pressure, various multigrid schemes, etc.) then we can  
perhaps understand which direction future development might want to go.

It is not always simple to compare speed for different codes running  
on different architectures and different CPUs (unless you know of a  
good way of measuring the number of floating point operations, FPOs,  
which is the more robust measure), and running these cases will take a  
little time, but perhaps for the above 3 reasons everyone with a code  
can run some of these comparisons.

Paul Tackley (cc) or somebody in his group might be able to run these  
comparisons relatively quickly using his code, and this could be a  
good place to begin.

Cheers!
John

On Aug 12, 2010, at 10:19 AM, Shijie Zhong wrote:

>
> I apologize in advance if this topic is not of interest to you.
>
> At the GLADE meeting, there were some good discussions on the need  
> for more
> benchmark, particularly regarding timing and speed. For CitcomS, our  
> 2008 G^3
> paper provides quite extensive benchmark calculations for Stokes'  
> flow,
> isochemical and thermochemical convection with large viscosity  
> contrast (up to
> 1e7). In Table 1 of this paper, we also include some information on  
> the speed
> and CPU time for a typical calculation, and scaling up to 3000 cores.
>
> Needless to say, more benchmarks and comparisons with other codes  
> will be
> helpful. If any of you are interested in doing this, I would be more  
> than happy to
> participate or take the lead. I can provide all those solutions  
> published in the
> paper including analytical solutions for Stokes' flow.
>
>
>
> Shijie Zhong
> Department of Physics
> University of Colorado at Boulder
> Boulder, CO 80309
> Tel: 303-735-5095; Fax: 303-492-7935
> Web: http://anquetil.colorado.edu/szhong