> I wish I could, but this behaviour only shows up on this peculiar data
> set :(
It always happens at the same time ?

Yes.
Perhaps debugging the process will sort things out ?
 

> Unfortunately, the process is very long, there are several
> optimizations in the process, the whole thing in a EM-like algorithm,
> and the crash does not occur with the first image, it is later.
Can you observe some 'funky' memory behaviour while the process is
running ? For example, does the memory keeps increasing after each dataset ?

Good question, in fact it should because I'm saving the result in a list before I pickle it (but in fact I have to change this process as pickle cannot handle the images I'm using, but that's another problem). So it should increase, but not too much. I'll check this.

Matthieu