[aspect-devel] Checkpoint I/O access

[Rene Gassmoeller]

Hi all,
for a computing time proposal I am trying to figure out how the I/O
operations of ASPECT's restart functionality work. I have found that the
Triangulation::save() function saves most of the data (i.e. mesh and
solution), but have nowhere found a clear note on how this is actually
done. In particular, I would like to know if all processes access the
data file and append their data into it (all at the same time or
sequentially?), or if the data is send via MPI-IO. From the
documentation it seems like every process has to access the file. While
loading the snapshot, does every process read the whole (potentially
large) restart file, does each process only read its part of the file,
or is the file read by process 0 and distributed afterwards? It would be
great if somebody has some insight on this, that would save me quite
some time digging through the code :-).

Best,
Rene

-- 
Rene Gassmoeller

2.5/Geodynamic Modelling
Tel.: +49 (0)331/288-28744
Fax:  +49 (0)331/288-1938
Email: rengas at gfz-potsdam.de
___________________________________

Helmholtz Centre Potsdam
German Research Centre for Geosciences GFZ
Telegrafenberg, 14473 Potsdam