How to reflect changes after editing the contents of crontab file directly. There is no need to restart cron after changing crontab.
On Linux, it checks the modification time of cron every minute and reloads if there is a change, so change of the file of cront if you do, your changes will take effect immediately without having restart cron.
[vagrant@localhost ~]$ /etc/rc.d/init.d/crond status
crond (pid 2614) を実行中…