Table of Contents
How does a context switch happen?
A context switch occurs when the kernel transfers control of the CPU from an executing process to another that is ready to run. The kernel first saves the context of the process. This indicates the point in the executable code that the CPU had reached when the context switch occurred.
Is context switching part of interrupt handling?
Context Switching Triggers Interrupt Handling: The hardware switches a part of the context when an interrupt occurs. This happens automatically. Only some of the context is changed to minimize the time required to handle the interrupt.
What is interrupt switching?
Interrupt context switching is a broad description that encompasses various switching paths—fast switching, optimum switching, and CEF—and includes the following steps: The interface processor detects a packet and moves the packet into input/output memory. The interface processor generates a receive interrupt.
What is the difference between context switch and interrupt?
Both are different concepts and there is no comparison. Context switching is saving the context of one task/thread and load and run the other high priority task/thread. Interrupt handling is responding to the event / interrupt.
What is process context and interrupt context?
When executing a interrupt handler or bottom half, the kernel is in interrupt context. Recall That process context is the mode of operation the kernel are in while it’s executing on behalf of a process– For example, executing a system call or running a kernel thread.
What is the difference between context switch and swapping?
A context switch occurs when the kernel switches contexts when it transfers control of the CPU from one process to another already ready to run state. Swapping happens when the entire process is moved to the disk.
How context switch happens in Linux?
Context switching is an essential feature of multitasking operating systems. These context switches occur as a result of processes voluntarily relinquishing their time in the CPU or as a result of the scheduler making the switch when a process has used up its CPU time slice.
What is the context of an interrupt?
Interrupt context is when the interrupt occurs state/priority goes to interrupt handler, and current process stops/saves until we complete interrupt, Interrupt context is not time consumable, non preemptable, It cannot go into the sleep.
How slow is a context switch?
A context switch interval is the length of time between desired context switches. In a periodic hard real-time system, the context switch interval cannot be longer than the period of the highest-frequency process; in some systems, this could be as short as 1 millisecond.