Chris Emery：CAMx is stable on many combinations of hardware, operating system and compiler. If you are experiencing instability please provide some information about the problem (i.e., the error message and associated CAMx run script) as well as your hardware and software environment (i.e., compiler version, operating system version and MPICH version).
Chris Emery：In our experience, Portland Group (PGF90) has the best track record. Many people use IFORT successfully. However, we have recent information that starting from IFORT v16 and onward, there is known bug interacting with certain Linux GLIBC library versions. This can cause CAMx and other programs to crash.
Chris Emery： There is no default number of emission source groups for PSAT. However, if the number of source groups times source regions are large, CAMx may crash with a segmentation fault because the total number of tracers exceeds a number that can be represented by a single-precision integer (2^31 = 2.15x10^9 = 8.6 GB). In the next release of CAMx, we are including a check on the total number of tracers to avoid segmentation faults and to stop with a useful error message. Later versions of CAMx will change the number of tracers to a double-precision integer.