Asked By
m.smith
40 points
N/A
Posted on - 06/28/2011
Hi folks,
Kindly tell me What is the difference between internal fragmentation and external fragmentation?
Also describe that What is the purpose of Timing signal in Synchronous communication?
Thanks.
Difference between Internal and External Fragmentation
Fragmentation happens in a dynamic memory allocation system when many of the free blocks are too small to fulfill any request.
-
External Fragmentation occurs when a dynamic memory allocation algorithm allocates some memory and a small piece is left over that cannot be effectively used.
-
Internal fragmentation is the space wasted inside of allocated memory blocks because of limitation on the allowed sizes of allocated blocks.
A timing signal (or clock) is needed to identify the boundaries between the bits (in practice it is preferable to identify the Centre of the bit – since this usually indicates the point of maximum signal power) transferred by the physical layer of a network.
Difference between Internal and External Fragmentation
Hello M.Smith
The principle of fragmentation is simple. When a program in the computer needs memory, it is being allocated in chunks. When the program finishes with it, it can free it back to the computer. Fragmentation, is the process where storage space is not being used efficiently and reduces the performance of the computer.
In internal fragmentation, more memory is allocated than necessary. The memory that is allocated to the programs, is in chunks divisible by 4,8 or 16. If a program requires 23 bytes, it will get 24. And when this happens, the excess memory goes to waste. That unusable memory is Internal Fragmentation.
External Fragmentation is a weakness of storage allocation when they fail to order memory used by programs efficiently. Even though free storage is available, it is unusable because it is divided into pieces too small that do not satisfy the application's demands.
The idea of Timing Signal in Synchronous communication means that if you violate timing information, you could risk sampling the data twice or miss a sample.
I hope this will help you .
Randolph
