Portability of ADIOS2 output files between different platforms.

[francesco-ballarin]

Dear ADIOS2 community,
I am a beginner in ADIOS2, and with this question I would like to assess whether I can expect to be able to read on (say) a arm64 platform output files generated by ADIOS2 on a amd64 one.

Further details to my query are:

• I searched for keywords like "portable" and "portability" in this repository and on the website, but could only find those words associated with the code itself, rather than output files. The one instance where output files were clearly mentioned was a negative one.
• my output format is either BP4 or BP5. C++ types I am willing to save are mainly strings, integers and floats.
• I do not call ADIOS2 myself, but I do so through a library that I use. If the way they call ADIOS2 is relevant in answering the question, and you are willing to skim through a couple of files to see how they use ADIOS2, these are the relevant files: file 1, file 2 and file 3

Thanks :)

[williamfgc]

BP files are binary and use standard C++ types, so in principle it's portable. As you saw some gotchas can happen with types that can change their underlying alignment. I would say give it a try and report back if there are issues. It's a common use case to write/read the data on different architectures (e.g. Summit). Hope it helps.

[francesco-ballarin]

Thanks @williamfgc. I'll give it a try then, and open an issue in case something goes wrong.