Multiple processor scheduling,

Published: 20 July 2021
on channel: SGVU Computer Application E-learning Channel

Fundamental of Operating System
Mr. Arjan Singh
Learning Centre of Excellence with Google, Suresh Gyan Vihar University, Jaipur, Rajasthan.
https://www.gyanvihar.org/school/lear...

About Tutorial:
In multiple-processor scheduling multiple CPU’s are available and hence Load Sharing becomes possible. However multiple processor scheduling is more complex as compared to single processor scheduling. In multiple processor scheduling there are cases when the processors are identical i.e. HOMOGENEOUS, in terms of their functionality, we can use any processor available to run any process in the queue.

Approaches to Multiple-Processor Scheduling –
One approach is when all the scheduling decisions and I/O processing are handled by a single processor which is called the Master Server and the other processors executes only the user code. This is simple and reduces the need of data sharing. This entire scenario is called Asymmetric Multiprocessing.

A second approach uses Symmetric Multiprocessing where each processor is self scheduling. All processes may be in a common ready queue or each processor may have its own private queue for ready processes. The scheduling proceeds further by having the scheduler for each processor examine the ready queue and select a process to execute.

Processor Affinity –
Processor Affinity means a processes has an affinity for the processor on which it is currently running.
When a process runs on a specific processor there are certain effects on the cache memory. The data most recently accessed by the process populate the cache for the processor and as a result successive memory access by the process are often satisfied in the cache memory. Now if the process migrates to another processor, the contents of the cache memory must be invalidated for the first processor and the cache for the second processor must be repopulated. Because of the high cost of invalidating and repopulating caches, most of the SMP(symmetric multiprocessing) systems try to avoid migration of processes from one processor to another and try to keep a process running on the same processor. This is known as PROCESSOR AFFINITY.

On this page of the site you can watch the video online Multiple processor scheduling, with a duration of hours minute second in good quality, which was uploaded by the user SGVU Computer Application E-learning Channel 20 July 2021, share the link with friends and acquaintances, this video has already been watched 66 times on youtube and it was liked by 0 viewers. Enjoy your viewing!

3,763