keskeytyskäsittelijöitä

Keskeytyskäsittelijöitä, often translated as interrupt handlers or interrupt service routines (ISRs), are essential components in computer systems responsible for managing hardware interrupts. When a hardware device needs the processor's attention, such as a keyboard press, a network packet arrival, or a disk operation completion, it generates an interrupt signal. This signal diverts the processor from its current task to execute a specific piece of code.

The interrupt handler is this specialized code. Its primary role is to acknowledge the interrupt, determine the source of the interrupt, and then perform the necessary actions to service the device. This might involve reading data from the device, updating system status, or signaling to other parts of the operating system that an event has occurred. Once the interrupt handler has completed its task, it typically returns control to the interrupted program, allowing it to resume execution as if nothing had happened, or at least with minimal disruption.

The design and efficiency of interrupt handlers are critical for system responsiveness and performance. Long-running interrupt handlers can block other interrupts, leading to dropped data or system sluggishness. Therefore, interrupt handlers are usually designed to be as short and efficient as possible, often deferring complex processing to background tasks. Operating systems manage a table of interrupt vectors, where each vector points to the address of the corresponding interrupt handler, ensuring that the correct routine is executed for each type of interrupt.