GATE - 2004 | OS | Consider the following statements with respect to user-level threads

GATE - 2004 [Operating System]

Question

Consider the following statements with respect to user-level threads and kernel supported threads

 

(i). context switch is faster with kernel-supported threads

(ii). for user-level threads, a system call can block the

     entire process

(iii). Kernel supported threads can be scheduled independently

(iv). User level threads are transparent to the kernel

Which of the above statements are true?
(A) (ii), (iii) and (iv) only
(B) (ii) and (iii) only
(C) (i) and (iii) only
(D) (i) and (ii) only

 

Solution:

Option (A) is Correct.

→ The user-level thread context switch is faster than kernel-level threads. Statement (i) is false.

→ If one user-level thread performs a blocking operation then the entire process will be blocked. Statement (ii) is true.

→ User-level threads are threads that are transparent to the kernel. Because user-level threads are created by users. Statement (iv) is true.

→ Kernal-supported threads can be scheduled independently, which is based on OS. Statement (iii) is true.

Thank You