The focus is on test execution time also. There will be 100's of test cases and each test case will have several cmds to be executed over n number of nodes. Currently using Net::SSH::Perl, my test case takes 6 secs to run on 3 different hosts involving a total of 70 system cmds. I am very happy with Net::SSH::Perl module. But multithreading with Net::SSH::Perl gives segv when I try to join the thread. That's why I was experimenting with fork and exec. Multithreading with Net::OpenSSH works fine. And so also fork and exec. Perhaps will have to switch to Net::OpenSSH instead of Net::SSH::Perl