4 votes 4 votes Here what are the number of context switches ? Is it 5 or 6? Do we consider context switch before P1 (i.e during the start) ? Operating System operating-system round-robin-scheduling context-switch + – Xylene asked Aug 12, 2017 Xylene 13.0k views answer comment Share Follow See all 5 Comments See all 5 5 Comments reply Gaurav Joshi commented Aug 12, 2017 reply Follow Share 5 we dont count the starting one until it is mentioned in the question. 1 votes 1 votes Tushar03 commented Sep 17, 2021 reply Follow Share In Galvin ,it is given that In Round Robin if time quanta is less than process burst time then even for single process in ready queue , context switching will happen then why here P3 context switches are not being considered ? 0 votes 0 votes minalBallav commented Sep 18, 2021 i edited by minalBallav Sep 18, 2021 reply Follow Share @Tushar03 Round robin is the preemptive process scheduling algorithm. Each process is provided a fix time to execute, it is called a quantum. Once a process is executed for a given time period, it is preempted and other process executes for a given time period. Round robin scheduling is similar to FCFS scheduling, except that CPU bursts are assigned with limits called time quantum. If the process finishes its burst before the time quantum timer expires, then it is swapped out of the CPU just like the normal FCFS algorithm. A scheduling discipline is preemptive if, once a process has been given the CPU can take away. The strategy of allowing processes that are logically run able to be temporarily suspended is called preemptive scheduling and it is contrast to the "run to completion" method... https://gateoverflow.in/147415/os-round-robin-scheduling?show=343480#a343480 https://gateoverflow.in/188697/context-switch https://gateoverflow.in/75651/context-switch https://gateoverflow.in/202650/operating-system 0 votes 0 votes Tushar03 commented Sep 18, 2021 reply Follow Share @minalBallav , my doubt is , for single process , can we consider context switches if time quanta of it is less that burst time in RR. in Galvin an example is taken like that where they showed the consideration of context switches of single process in cpu . 0 votes 0 votes minalBallav commented Sep 18, 2021 i edited by minalBallav Sep 18, 2021 reply Follow Share @Tushar03 Burst time is - m units (let 10) , time quantum - q units (let 5 or 6 or 4) , q < m .. [m/q ] – 1 In round robin, context switching always takes place even if there’s only one process... A context switch is the process of storing the state of a process or thread, so that it can be restored and resume execution at a later point. This allows multiple processes to share a single central processing unit (CPU), and is an essential feature of a multitasking operating system. The precise meaning of the phrase “context switch” varies. In a multitasking context, it refers to the process of storing the system state for one task, so that task can be paused and another task resumed…. It clearly says " Assume that dispatching the process first time is not counted as a context switch." so number of context switch = 0 as there is only one single process.... 0 votes 0 votes Please log in or register to add a comment.
5 votes 5 votes Here total 5 context switches ocur . `p1 - p2 p2 - p3 p3- p4 p4 - p1 p1- p3 during start there is context switch but we don't consider that case. Bikram answered Aug 30, 2017 Bikram comment Share Follow See 1 comment See all 1 1 comment reply Dharmendra Lodhi commented Oct 14, 2018 i edited by Dharmendra Lodhi Oct 14, 2018 reply Follow Share what about last context switch when P3 will terminate i think 6 context switches should be there. https://cs.stackexchange.com/questions/74049/does-a-context-switch-happen-when-a-process-has-terminated 0 votes 0 votes Please log in or register to add a comment.
1 votes 1 votes A context switch occurs when a computer’s CPU switches from one process or thread to a different process or thread. It should be 5. Surya Dhanraj answered Aug 12, 2017 Surya Dhanraj comment Share Follow See all 0 reply Please log in or register to add a comment.