[DiSCUSS] restarting the system in UTS and ITS and test it again.

[weizihan0110]

Hi all:
        I looked through a lot of codes in unit tests or integration tests and 
found that the tests test something we modify but haven't restarted the system 
and test it again.
        Should we add some codes to restart the system in UTS and ITS and test 
it again?