What will happen if I run crn job that is already running in laravel

I would like to know, what will happen If I have one cron schedule for every 5 minutes, which updates data in system and it takes about 30 mins to complete its process but if the same cron runs again after 5 minutes, will it stop executing already running process and starts from again, leaving half of data not updated?

Any help would be good.

via Chebli Mohamed