Different residuals between serial and decomposed parallel case

Greetings,

In running the cavity tutorial I've noticed that the residuals differ between the serial case and the decomposed case.

The steps I followed are:

• run the serial case icoFoam > logSerial
• Without changing anything except the decomposeParDict file changed the number of subdomains to 2 and used the method scotch, then run: mpirun -n 2 icoFoam -parallel > logParallel

I run it for only 2 time steps, then compare the log files:

Why there is a difference between the serial and parallel case?

Note: I am using the version 2306 on Ubuntu 22.04