Computer & Technology
Fragmentation And Types Of Fragmentation In Operating System
Computer & Technology
Fragmentation means isolated or incomplete part. There are two types of Fragmentation. One is External Fragmentation ans other one is Internal Fragmentation
Meaning of Fragmentation
In the words of layman, Fragmentation means isolated or incomplete part. Fragmentation means something is broken into parts that are detached, isolated or incomplete.
Types of Fragmentation
There are two types of Fragmentation :-
1) External Fragmentation
2) Internal Fragmentation
a) It exists when there us enough total memory space available to satisfy a request, but available memory space are not contiguous.
b) Storage space is fragmented into large number of small holes.
c) Both first fit and best fit strategies suffer from this.
d) First fit is better in some systems, whereas best fit is better for other.
e) Depending on the total amount of memory storage, size, external fragmentation may be minor or major problem.
f) Statistically N allocated block, Another 0.5 N blocks will be lost to fragmentation. The 1/3 of memory is unusable. It is called
50 - Percent Rule
Consider a multiple partition allocation scheme with a hole of 18,462 bytes. The next process request with 18,462 bytes. If we allocate, we are left with a hole of 2 bytes.
The general approach to avoid this problem is to :-
a) Break physical memory into fixed sized blocks and allocate memory in units based on block size.
b) Memory allocated to a process may be slightly large than the requested memory.
* The difference between two numbers is Internal fragmentation.
Solution to Internal Fragmentation
The goal is to shuffle the memory content. so as to place all free memory together in one large block.
It is not always possible due to :-
If relocation is static and done at assembly or load time
It is possible
Only if relocation is dynamic and is done at execution time
2) Permit the logical address space to the processes to be non-contagious.
Did you like this resource? Share it with your friends and show your love!
Responses to "Fragmentation And Types Of Fragmentation In Operating System"
Notify me by email when others post comments to this article.
Do not include your name, "with regards" etc in the comment. Write detailed comment, relevant to the topic.
No HTML formatting and links to other web sites are allowed.
This is a strictly moderated site. Absolutely no spam allowed.
to fill automatically.
(Will not be published, but
to validate comment)
Type the numbers and letters shown on the left.
Subscribe to Email
Get Jobs by Email
Forum posts by Email
Articles by Email
Awards & Gifts
Last 7 Days
Shafeer V U
Hafeezur Rahman P
ISC Technologies, Kochi - India. © All Rights Reserved.