Scheduling (computing)

Kernel preemption

In computer operating system design, kernel preemption is a property possessed by some kernels (the cores of operating systems), in which the CPU can be interrupted in the middle of executing kernel code and assigned other tasks (from which it later returns to finish its kernel tasks). That is to say, the scheduler is permitted to forcibly perform a context switch (on behalf of a runnable and process) on a driver or other part of the kernel during its execution, rather than co-operatively waiting for the driver or kernel function (such as a system call) to complete its execution and return control of the processor to the scheduler when done. It is used mainly in monolithic and hybrid kernels, where all or most device drivers are run in kernel space. Linux is an example of a monolithic-kernel operating system with kernel preemption. The main benefit of kernel preemption is that it solves two issues that would otherwise be problematic for monolithic kernels, in which the kernel consists of one large binary (rather than multiple "services", as in a microkernel-based OS like Windows NT/Vista/7/10 or macOS). Without kernel preemption, two major issues exist for monolithic and hybrid kernels: * A device driver can enter an infinite loop or other unrecoverable state, crashing the whole system. * Some drivers and system calls on monolithic kernels can be slow to execute, and cannot return control of the processor to the scheduler or other program until they complete execution. (Wikipedia).

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From playlist Precalculus

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From playlist Precalculus - College Algebra/Trigonometry

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Kernel Recipes 2019 - RCU in 2019

RCU has seen lots of changes in the last 2 years. Of note is the RCU flavor consolidation and tree RCU’s lock contention improvements. There have been also improvements with static checking, fixes to scheduler deadlocks and improvements to RCU-based linked lists. This talk starts with an i

From playlist Kernel Recipes 2019

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From playlist Embedded Recipes 2018

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From playlist Kernel Recipes 2019

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From playlist Kernel Recipes 2015

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From playlist Kernel Recipes 2019

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From playlist Kernel Recipes 2017

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From playlist Embedded Recipes 2019

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From playlist I am Taking Pre-Calculus

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From playlist DEFCON 19

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From playlist Basics: Precalculus

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From playlist Course 1: Precalculus

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From playlist Kernel Recipes 2018

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