Install libproc-queue-perl by entering the following commands in the terminal:
sudo apt update sudo apt install libproc-queue-perl
Perl module to limit the number of child processes
Proc::Queue lets you parallelise a perl program using the fork, exit, wait and waitpid calls as usual but without taking care of creating too many processes and overloading the machine. . It redefines perl fork, exit, wait and waitpid core functions. Old programs do not need to be reprogrammed, only the use Proc::Queue ... sentence has to be added to them.