H5Part development and discussion

[Achim Gsell <achim.gsell AT psi.ch>]

Hi Mark

On Jul 8, 2010, at 5:54 PM, Mark Howison wrote:

> I'm still working through the H5Block code, and I wanted to find out
> more about the original design decisions for handling arbitrary ghost
> zones, which introduces alot of complexity in "dissolving" them. I
> don't see an easy way to get around the O(n) space required in the
> H5Block file struct to store every proc's field layout for use in the
> ghost zone routines.

I implemented arbitrary ghost zone on request of LBNL ... But is the O(n) 
space required really an issue? The layout occupies 
6*sizeof(h5_int64_t)*nprocs bytes per process. With 64k cores it's just 3MB 
(or 0.0022% of the available memory we have on Franklin/core).

> Do we need to support arbitrary ghost zones?

Good question, actually I don't know. As far as I know, we don't need them at 
PSI. 
> 

Achim