Operating Systems - Context Switch - Cost & Causes
Which component is primarily responsible for saving and restoring CPU registers during a context switch?
Which component is primarily responsible for saving and restoring CPU registers during a context switch?
easy🔍 Pattern Recognition Q11 of Q15
Step-by-Step Solution
Step 1: Understand the role of PCB
The PCB stores the CPU register states and other process information needed to resume execution later.Step 2: Differentiate from scheduler and interrupt handler
The scheduler decides which process runs next but does not save registers; the interrupt handler triggers context switches but does not save registers itself.Step 3: MMU role
The MMU handles memory address translation, unrelated to register saving.Final Answer:
Option D -> Option DQuick Check:
PCB contains saved CPU state -> correct component for saving/restoring registers.
Quick Trick: PCB = process snapshot including CPU registers [OK]
Common Mistakes:
MISTAKES- Confusing scheduler with register saving
- Assuming interrupt handler saves registers
- Thinking MMU handles CPU state
Trap Explanation:
PITFALL- Scheduler and interrupt handler are involved in context switching but do not save CPU registers; PCB holds the saved state.
Interviewer Note:
CONTEXT- Tests candidate's understanding of OS components involved 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