laravel 5 shedule runs with delay every day

I have a problem with schedule tasks in laravel 5.

The point is that I run schedule at 20:00 every day, and I put some results in database after exetuting of the task. The task collect different daily statisctic.

I have noticed that previosly task was running exactly at 20:00, then at 20:01, now it has arrived till 20:05.

Does anybody faced with the same issue? Any ideas where to look for solving that problem?

via Chebli Mohamed