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process scheduling 標籤的文章。
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process scheduling 標籤的文章。
顯示所有文章
Basic concept
- In a single-processor system, only one process can run at a time
- Any others must wait until the CPU is free and can be rescheduled.
- Multiprogramming is to have some process running at all times to maximize CPU utilization.
- A process is executed until it must wait, typically for the completion of some I/O request.
- Several processes are kept in memory at one time, when one process has to wait, the operating system takes the CPU away from that process and gives the CPU to another process.
- Every time one process has to wait, another process can take over use of the CPU.
- Scheduling of this kind is a fundamental operating-system function.
- Almost all computer resources are scheduled before use. The CPU is, of course, one of the primary computer resources. Thus, its scheduling is central to operating-system design.
