Difference Between Internal and External fragmentation

In this post, we will understand the difference between internal and external fragmentation −

Internal Fragmentation

• The difference between the memory allocated and the space required is known as internal fragmentation.

• In this fragmentation, fixed-sized memory blocks are used to process data.

• This process occurs when a method or process is larger than the required memory.

• The method used in internal fragmentation is ‘best-fit’ block.

• It occurs when the memory is divided into fixed sized partitions.

External Fragmentation

• The unused spaces that is formed between fragments of non-contiguous memory, which are too small to help with a new process, is known as external fragmentation.

• It uses variable-sized memory blocks to process data.

• This type of fragmentation occurs when a method or process is removed.

• It can be used with compaction, paging and segmentation.

• External fragmentation occurs when memory is divided into variable sized partitions (that is based on size of process).