Operating Systems - Context Switch - Cost & Causes
Which of the following best describes the primary role of the Process Control Block (PCB) during a context switch?
Which of the following best describes the primary role of the Process Control Block (PCB) during a context switch?
easy🔍 Pattern Recognition Q1 of Q15
Step-by-Step Solution
Solution:
Step 1: Understand PCB's role in context switching
The PCB stores the CPU state (registers, program counter) so the process can resume correctly after a context switch.Step 2: Analyze other options
Managing the scheduling queue is the scheduler's job, not the PCB's. Memory allocation is handled separately by the OS memory manager. The PCB does not perform saving/restoring automatically; the OS uses PCB data to save and restore CPU state.Final Answer:
Option A -> Option AQuick Check:
PCB holds CPU state for process resumption [OK]
Quick Trick: PCB stores CPU state, not scheduling or memory [OK]
Common Mistakes:
MISTAKES- Confusing PCB with scheduler's job
- Assuming PCB handles memory allocation
- Believing PCB automates register saving
Trap Explanation:
PITFALL- Candidates often think PCB manages scheduling or memory, or that it itself saves registers, but it only stores the saved state.
Interviewer Note:
CONTEXT- Tests understanding of PCB's fundamental role in context switching.
Master "Context Switch - Cost & Causes" in Operating Systems
Want More Practice?
15+ quiz questions · All difficulty levels · Free
Free Signup - Practice All QuestionsMore Operating Systems Quizzes