Q38.Marks: +2.0UGC NET Paper 2: Computer Science 26th Nov 2021
In a file allocation system, the following allocation schemes are used :
A. Contiguous
B. Indexed
C. Linked allocation
Which of the allocation scheme(s) given above will not suffer from external fragmentation? Choose the correct answer from the options given below :
1.A only
2.B and C only✓ Correct
3.A and B only
4.C only
Solution
The correct option is (2)
Concept:-
Internal fragmentation happens when a process is given more memory than it needs and only a little amount of space is left unused. When memory blocks are present but non-contiguous, external fragmentation occurs, and the impending memory request cannot be filled.
Key Points
External fragmentation is not a concern with linked and indexed allocation, whereas external fragmentation was a problem with contiguous allocation.
When it comes to allocating disc space, there are a variety of options. We must choose the optimal file allocation mechanism because it will have a direct impact on system performance and efficiency. The allocation approach allows us to access files as well as use the drive.
One of the most popular allocation methods is contiguous allocation. Contiguous allocation refers to allocating a block in such a way that all of the blocks on the hard disc receive the same physical block.
Another technique for file allocation is the indexed allocation approach. We have an additional block in the index allocation procedure, which is known as the index block.
The disadvantages of the contiguous allocation approach are overcome by the linked list allocation method. Each file is considered as a linked list of disc blocks in this file allocation approach.
