📜  长期和短期调度程序之间的区别

📅  最后修改于: 2021-09-14 01:21:02             🧑  作者: Mango

先决条件 – 进程调度程序
长期调度程序也称为作业调度程序。长期调度器对选择到系统进行处理的程序进行调节。在这种情况下,程序在队列中设置,并根据要求选择最好的一项作业,并从作业池中获取进程。它规定了多道程序(DOM)的程度。

短期调度程序也称为CPU 调度程序。短期调度程序确保哪个程序适合或重要处理。它规定了较少的 DOM(多程序设计程度)。

长期和短期调度程序之间的区别:

S.NO Long-Term Scheduler Short-Term Scheduler
1. Long-Term Scheduler takes the process from job pool. Short-Term Scheduler takes the process from ready queue.
2. Long-Term Scheduler is also known as Job Scheduler. Short-Term Scheduler is also known as CPU Scheduler.
3. In Long-Term Scheduler, the programs are setup in the queue and as per the requirement the best one job is selected. In Short-Term Scheduler no such queue is exist.
4. It regulates the more DOM (Degree of Multi-programming). It regulates the less DOM (Degree of Multi-programming).
5. It regulates the programs which are selected to system for processing. It ensures which program is suitable or important for processing.
6. Speed is less than the short-term scheduler. Speed is very fast as compared to long-term scheduler.
7. Long-Term Scheduler changes the process state from New to Ready. Short-Term Scheduler changes the process state from Ready to Running.
8. Time-sharing operating systems have no long-term scheduler. It may be minimal in time-sharing system.
9. It select a good process, mix of I/O bound and CPU bound. It select a new process for a CPU quite frequently.