[Captain Convergence]

Dear all,

I am using a post process script executed in the HPC of my institution for generating the streaklines of my simulation carried out in a multiblock mesh. The data is exported in .plt format and the reader is “VisItTecplotBinaryReader”. I am calling the paraview/pvbatch-5.9.0 as :

mpiexec -np 6 pvbatch --force-offscreen-rendering $my_script.py

When I run this locally on my laptop (for a small amount of timesteps) it works completely fine but I have been doing some tests on the HPC and as you can see in the attached screenshot (6_CPUs.jpeg), there are missing blocks in the rendering. It is worth to mention that they appear and dissappear and it is not always the same blocks that do that. It doesn’t seem a problem of the particle tracer filter because it tracks the particles motion successfully (it is just not visible).

I have also noticed that the regions that appear and disappear and the frequency of their disappearance depend on the number of CPUs that I using. In the first image I was using mpiexec -np 6 pvbatch… and several domains where poping in and out. In the following images I was using directly pvbatch… and the appearance and disappearance is not instantaneous, it is a gradual vanishing. The next images "single_CPUs_part1.jpeg" and "single_CPUs_part2.jpeg" are taken with almost no time difference in the video.

Does anyone have an idea of why the particle tracers become invisible sometimes when they go over the blocks?

Thanks in advance!