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in fcfs scheduling there is a shortcoming
that is if any rocess of maximum brust time is first ome. and after that many short burst time process come. then smaller pocesses have to wait for a long time untill the max brust time process complete their execution.
in case of shortest job first it applied the method to give shortest t\burst time job to processer first.
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Explain with an example first come first serve scheduling algorithm?
By far the simplest CPU-scheduling algorithm is the first-come, first-served (FCFS) scheduling algorithm. With this scheme, the process that requests the CPU first is allocated the CPU first. The implementation of the FCFS policy is easily managed with a FIFO queue. When a process enters the ready queue, its PCB is linked onto the tail of the queue. When the CPU is free, it is allocated to the process at the head of the queue. The running process is then removed from the queue. The code for FCFS scheduling is simple to write and understand. The average waiting time under the FCFS policy, however, is often quite long. Consider the following set of processes that arrive at time 0, with the length of the CPU-burst time given in milliseconds:
Disadvantage of time sharing?
There are advantages and disadvantages when purchasing a time share for your vacation destination. The main disadvantages are depreciation, and the inability to use your timeshare due to scheduling conflicts.
What are the relationships between priority and FCFS of CPU scheduling algorithms?
this is my doubt about the non-preemptive priority scheduling. i m doing bachelor of engineering in IT and this question in end semester exam. the question is as follows:Assume you have the following jobs to be executed with one processor, with the jobs arriving in the order listed here:Process Burst Time PriorityP1 80 5P2 20 1P3 10 3P4 20 2P5 50 4Suppose the system uses priority scheduling. Draw Gantt chart and calculate average waiting time for the processes.My doubt is:suppose if we were to use non-preemptive priority scheduling, the question says the jobs arriving in the order listed, so as per the order P1 will arrive first so it will get the CPU first and in non-preemptive once a job gets CPU it will not leave CPU till the process finishes, then as per the order P2 will come and same thing repeats.... so it acts like FCFS scheduling and priority is of no use here. But my lecturer says we have to follow the priority and P2 will come first, but the line the jobs arriving in the order listed is still not letting me agree with my lecturer. Can anyone help out?
What is disk scheduling in operating system?
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The priority scheduling algorithm is a kind of CPU scheduling algorithm where the processes that wait for the CPU are scheduled according to their priority..
Briefly define FCFS scheduling?
First-Come, First-Serve (FCFS) scheduling is one of the simplest scheduling algorithms in the realm of operating systems, and its implementation offers a straightforward approach to process management. In FCFS scheduling, processes are executed in the order they arrive in the ready queue, essentially adhering to a first-in, first-out (FIFO) strategy. The fundamental principle behind FCFS is straightforward: the first process to request the CPU gets executed first, and subsequent processes have to wait until the CPU is available again. The mechanism of FCFS scheduling is simple to understand and implement. When a process enters the system, it gets placed in the ready queue. The CPU scheduler picks the process at the head of the queue for execution and allocates the CPU to this process. The process continues to execute until it either finishes or gets blocked for I/O or some other reason, at which point the CPU is allocated to the next process in the ready queue. This cycle continues until all processes are executed. FCFS is non-preemptive, meaning once the CPU is allocated to a process, it retains control of the CPU until it completes its execution or gets blocked for some reason. This characteristic simplifies the scheduler design, making FCFS an attractive choice for simple systems or batch processing environments where jobs are more or less independent of each other. However, FCFS scheduling has its set of drawbacks. It can lead to the "convoy effect," where short processes have to wait for a long process to complete, leading to suboptimal CPU utilization. The average waiting time under FCFS scheduling can be high if long processes arrive at the queue early. Moreover, FCFS does not prioritize processes based on their importance or urgency, which can be a significant limitation in scenarios where certain processes require immediate attention. Despite its limitations, the simplicity and ease of implementation of FCFS scheduling make it a viable choice in specific scenarios, especially in systems with minimal process management requirements or in batch processing environments. It serves as a foundation for understanding more complex scheduling algorithms and provides a clear illustration of how process scheduling works at a basic level. In a nutshell, FCFS scheduling is a fundamental, easy-to-implement scheduling algorithm that executes processes based on their arrival order, adhering to a non-preemptive, first-in, first-out strategy. While it may not be the most efficient or versatile scheduling algorithm, its simplicity makes it a useful stepping stone in the study of operating system scheduling algorithms, paving the way for understanding more advanced scheduling strategies.
What kind of data structure is required to implement the round robin scheduling policy?
The circular queue data structure is required to implement the round robin scheduling policy. Round robin is similar to FCFS scheduling.
Explain with an example first come first serve scheduling algorithm?
By far the simplest CPU-scheduling algorithm is the first-come, first-served (FCFS) scheduling algorithm. With this scheme, the process that requests the CPU first is allocated the CPU first. The implementation of the FCFS policy is easily managed with a FIFO queue. When a process enters the ready queue, its PCB is linked onto the tail of the queue. When the CPU is free, it is allocated to the process at the head of the queue. The running process is then removed from the queue. The code for FCFS scheduling is simple to write and understand. The average waiting time under the FCFS policy, however, is often quite long. Consider the following set of processes that arrive at time 0, with the length of the CPU-burst time given in milliseconds:
Priority scheduling positive and negative points?
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Disadvantage of time sharing?
There are advantages and disadvantages when purchasing a time share for your vacation destination. The main disadvantages are depreciation, and the inability to use your timeshare due to scheduling conflicts.
What are the advantages and disadvantages to online appointment scheduling?
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What is the disadvantage of cpm?
There are several disadvantages of CPM or Critical Path Method. A few of the disadvantages are CPM is more complicated and complex, doesn't handle scheduling, and you can't estimate completion times.
Advantages and disadvantages of first come first serve scheduling?
First-come, first-served (FCFS) - sometimes first-in, first-served and first-come, first choice - is a service policy whereby the requests of customers or clients are attended to in the order that they arrived, without other biases or preferences. The policy can be employed when processing sales orders, in determining restaurant seating, on a taxi stand, etc. In Western society, it is the standard policy for the processing of most queues in which people wait for a service or two.
What are the relationships between priority and FCFS of CPU scheduling algorithms?
this is my doubt about the non-preemptive priority scheduling. i m doing bachelor of engineering in IT and this question in end semester exam. the question is as follows:Assume you have the following jobs to be executed with one processor, with the jobs arriving in the order listed here:Process Burst Time PriorityP1 80 5P2 20 1P3 10 3P4 20 2P5 50 4Suppose the system uses priority scheduling. Draw Gantt chart and calculate average waiting time for the processes.My doubt is:suppose if we were to use non-preemptive priority scheduling, the question says the jobs arriving in the order listed, so as per the order P1 will arrive first so it will get the CPU first and in non-preemptive once a job gets CPU it will not leave CPU till the process finishes, then as per the order P2 will come and same thing repeats.... so it acts like FCFS scheduling and priority is of no use here. But my lecturer says we have to follow the priority and P2 will come first, but the line the jobs arriving in the order listed is still not letting me agree with my lecturer. Can anyone help out?
What are the Advantage and disadvantages of retail trade?
Some advantages to working in the retail trade include flexible scheduling; and the ability to increase your pay with bonuses and commission. Disadvantages of working with in the retail trade include unreliable income and dealing with unhappy customers.
What is the difference between conventional C and embedd C?
Advantages: - Priority based premptive scheduling -multitasking -multithreading -better response time -valuable services like senaphore,mailbox,queues etc. Disadvantages: -expensive Advantages: - Priority based premptive scheduling -multitasking -multithreading -better response time -valuable services like senaphore,mailbox,queues etc. Disadvantages: -expensive
What is local scheduling and global scheduling?
i do no...............
