QUESTION 52 Which of the below is/are the operating-system managed threads that act on the...
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QUESTION 52
Which of the below is/are the operating-system managed threads that act on the core operating system?
I) Kernel – level threads
II) User – level threads
Show answer & explanation
Kernel-level threads are directly managed by the operating system and act on the core OS, receiving dedicated OS scheduling and resource management. User-level threads, by contrast, are managed by user-space thread libraries (not the OS) and require a user-space scheduler; the OS is unaware of their existence, so they do not directly act on the core OS.
Step-by-step Derivation:
Key distinction:
Kernel-level threads (I):
- Created and managed by the OS kernel
- OS scheduler directly manages them
- Each kernel thread receives its own time slice and system resources
- OS is fully aware of and acts upon these threads
User-level threads (II):
- Created and managed by user-space thread libraries (e.g., pthreads)
- OS has no direct awareness of them
- A single kernel thread may run multiple user-level threads via cooperative or preemptive scheduling within user space
- The OS does NOT directly manage or act on user-level threads; only the thread library does
Since the question asks for threads "that act on the core operating system" (i.e., managed by the OS), only kernel-level threads qualify.
Answer: (C) Only (I)