foreach() loop with MPI

[Ayoub Mansar]

Hello everyone, 

I am using a basilisk program in which I store some data using a foreach() loop over cells, the problem is that it works fine on serial, but as soon as I run it with MPI on a cluster I noticed that it only loops over a square 3D piece of my domain and not all of it.

I tried to force it by using foreach(serial), but I get the same results.

Any thoughts on what is causing that ?

Thanks in advance !

Ayoub,

[Ayoub Mansar]

I'll be very gatreful if anyone has an indication about this, I've been stuck for too long.

Thank you 

[Yi Dai]

Hi Ayoub, 

Since there is no information about your foreach() loop, maybe Antoon's illustration can be help here: http://basilisk.fr/sandbox/Antoonvh/The_Tree-Grid_Structure_in_Basilisk#indexing-and-mpi-load-balancing

[shine Sun]

Hello  Ayoub,

The foreach() function loops over the cells within the domain of each MPI thread. Maybe you should output the result for each thread seperately.

Cheers!

Shine Sun

[shine Sun]

Hello Ayoub,

In my experience, I just specify the output file name with the pid() number and remember that every processor outputs its own domain cells. For example, 

sprintf(fp, "output_%d", pid());

foreach() {

  ...

}

And every processor will output its file correctly in my simulations.

Hope this helps!

Shine Sun

[Ayoub Mansar]

Hello Shine  and Dyzr,

It worked fine printing with pid() !

Thank you so much for your help,

Ayoub

[Ning Wang]

Hello Shine,  Ayoub and Dyzr,

When I output data and write it to a file, whether serial or parallel, I always get missing columns for certain rows of data in the file, e.g. the top and bottom rows of this row have 8 data, but this row only has 5
If you have any comments about this please send me a reply

Thank you

Ning Wang

2022年11月24日木曜日 16:54:13 UTC+8 ayoubm...@gmail.com: