[Opm] Parallel output in OPM Flow

[Markus Blatt]

Hi, 

Nice to hear that there is some work on the output layer. I just have 
some questions.

On Thu, May 06, 2021 at 07:52:36AM +0000, Atgeirr Rasmussen wrote:
> [...] In the ACROSS project (see https://www.acrossproject.eu for 
>information), we intend to implement parallel output for OPM Flow. The 
>idea is to do this by using the Damaris software library 
>(https://project.inria.fr/damaris/) from INRIA, who are also part of 
>the ACROSS project, and will contribute to the implementation. We think 
>Damaris is a good fit for OPM. It is open source, has been shown to 
>provide good I/O scaling up to large process counts, and has been 
>previously applied in the reservoir simulation domain.
>

Can you please tell us what open source license Damaris uses. I could 
not find any information on the website and at 
https://gitlab.inria.fr/Damaris/damaris it says "No license. All rights 
reserved", but that is probably an oversight. No License file, no 
readme.

Can you point us to a publication where it is used for reservoir 
simulation? That would be interesting.

>So far, we see three important tasks related to this:
> - Refactoring in OPM Flow to enable the integration of Damaris. From what we have seen so far, any necessary refactoring will be improving the Flow code, and make it more flexible.
> - Integrating the Damaris library. We will ensure that this is an optional dependency, to minimize developer workload and hassle.

What does optional mean here? If there is no Damaris we fall back to our 
current way and only if it is there we get hdf5/parallel output? Or are 
there plans to support hdf5 without Damaris (which seems to be a lot 
more than just output: data processing, in situ visualization,...)? That 
would be cool.

Cheers,

Markus