Definition - What does Overrun mean?
In computing systems, an overrun happens when there is too much demand placed on a system, where it is not able to handle all of the processes and threads that are happening. IT pros might talk about a “CPU overrun” when the CPU is not able to handle demand, or an “interface overrun” when the OP crashes because of insufficient process handling capability.
Techopedia explains Overrun
One example of overrun is when a process has been started, and a computing system cannot complete a prior task before handling a new one, it might flag an overrun indicator. Various types of overrun errors alert users that something is wrong. Another example is in a network overrun error where techs can go in and look at workload to determine what the bottleneck is and why an error occurred.