Search results
Results from the WOW.Com Content Network
In this scheduling algorithm, once assigned to a queue, the process will not move to any other queues. Consider the following table with the arrival time, execute time and type of the process (foreground or background - where foreground processes are given high priority) to understand non pre-emptive and pre-emptive multilevel scheduling in ...
One common method of logically implementing the fair-share scheduling strategy is to recursively apply the round-robin scheduling strategy at each level of abstraction (processes, users, groups, etc.) The time quantum required by round-robin is arbitrary, as any equal division of time will produce the same results.
The scheduler is an operating system module that selects the next jobs to be admitted into the system and the next process to run. Operating systems may feature up to three distinct scheduler types: a long-term scheduler (also known as an admission scheduler or high-level scheduler), a mid-term or medium-term scheduler, and a short-term scheduler.
In computing environments that support the pipes-and-filters model for interprocess communication, a FIFO is another name for a named pipe.. Disk controllers can use the FIFO as a disk scheduling algorithm to determine the order in which to service disk I/O requests, where it is also known by the same FCFS initialism as for CPU scheduling mentioned before.
This is an alternative to the first-come first-served (FCFS) algorithm. The drive maintains an incoming buffer of requests, and tied with each request is a cylinder number of the request. Lower cylinder numbers indicate that the cylinder is closer to the spindle, while higher numbers indicate the cylinder is farther away.
Random scheduling (RSS) First In, First Out , also known as First Come First Served (FCFS) Last In, First Out ; Shortest seek first, also known as Shortest Seek / Service Time First (SSTF) Elevator algorithm, also known as SCAN (including its variants, C-SCAN, LOOK, and C-LOOK) N-Step-SCAN SCAN of N records at a time
The Worst-case Fair Weighted Fair Queueing (WF2Q) fixes it by adding a virtual start of service to each packet, and selects a packet only if its virtual start of service is not less than the current time. [3] The selection of the queue with minimal virtual finish time can be hard to implement at wire speed.
If the process uses all the quantum time, it is pre-empted and inserted at the end of the next lower-level queue. This next lower-level queue will have a time quantum that is more than that of the previous higher-level queue. This scheme will continue until the process completes or it reaches the base-level queue.