Are all post-processing function only using single CPU core?

Hi all,

I'm doing 3D eigenvalue simulations. I noticed that I can used pardiso direct solver to take advantage of multi-core CPUs.
However, when I went to the point of post-processing, e.g. exporting volume integral for all eigenmodes, the integration is only running on a single CPU-core. It's very slow as a single sequential thread. I'm Considering such process could be easily parallelized?
Is it possible that all post-processing can be updated with multiple-thread calculations?