Operating Systems Question Bank with Answers 20

Describe the differences among short-term, medium-term, and long-term scheduling.

Question:

Describe the differences among short-term, medium-term, and long-term scheduling.

Answer:

Short-term (CPU scheduler): selects a process from those that are in memory and ready to execute, and allocates the CPU to it.

Medium-term (memory manager): selects processes from the ready or blocked queue and removes them from memory, then reinstates them later to continue running. It is used especially with time-sharing systems as an intermediate scheduling level.

Long-term (job scheduler): determines which jobs are brought into the system for processing. It is responsible for controlling the degree of multi-processing.

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