This article explores the concept of internal and external fragmentation in computer systems.

Internal fragmentation refers to the wastage of memory resources when memory is allocated in blocks larger than necessary. This occurs due to the allocation of fixed block sizes, resulting in unused memory.

On the other hand, external fragmentation arises when memory blocks are allocated in a non-contiguous manner, creating gaps in memory. This reduces the availability of contiguous memory for larger tasks and can lead to insufficient memory for important operations.

Both internal and external fragmentation can ultimately lead to a reduction in available memory and inefficient memory usage.

To provide a clearer understanding, an analogy is drawn between internal fragmentation and a paper book with gaps between chapters, while external fragmentation is likened to a paper diary with randomly written pages.

By examining the causes, types, effects, and consequences of fragmentation, this article aims to shed light on this important aspect of computer memory management.

Causes and Types

Internal fragmentation occurs when memory is allocated in fixed block sizes, leading to wasted memory resources and the accumulation of unused memory over time. This type of fragmentation occurs inside larger memory blocks and can result in wasted space within allocated memory blocks. It is caused by the allocation of memory in blocks that are larger than necessary, which creates gaps between the allocated memory and the actual data being stored. These gaps can accumulate over time and create large amounts of unused memory, reducing the overall efficiency of memory usage.

In contrast, external fragmentation happens when memory blocks are allocated in a non-contiguous manner. This creates gaps or free memory spaces between the allocated blocks, reducing the availability of contiguous memory for larger tasks. It is caused by the allocation and deallocation of memory blocks, which can lead to a lack of available memory for important tasks. External fragmentation isolates sections of free memory that are too small for significant use and can create an overall reduction of free memory over time.

An analogy to explain internal fragmentation is a paper book with gaps between chapters, while an analogy for external fragmentation is a paper diary with randomly written pages.

Effects and Consequences

The effects and consequences of fragmentation include:

• Wasted memory resources and reduced availability of contiguous memory for larger tasks.

• Internal fragmentation occurs when memory is allocated in blocks larger than necessary, resulting in wasted space within allocated memory blocks. This can lead to a gradual accumulation of unused memory, reducing the overall efficiency of memory usage.

• External fragmentation happens when memory blocks are allocated in a non-contiguous manner, creating gaps in memory. This can result in a lack of available memory for important tasks and can isolate sections of free memory that are too small for significant use.

Over time, external fragmentation can lead to a reduction in free memory and hinder the execution of larger tasks that require contiguous memory allocation.

Analogies

Analogies can be used to help understand the concept of fragmentation and its effects.

When it comes to internal fragmentation, a paper book with gaps between chapters serves as a suitable analogy. Just as unnecessary empty space between chapters in a book wastes paper resources, internal fragmentation occurs when memory is allocated in blocks larger than necessary, resulting in wasted memory resources. This can accumulate over time, creating large amounts of unused memory within allocated blocks.

On the other hand, external fragmentation can be illustrated by a paper diary with randomly written pages. Similar to how the non-contiguous arrangement of pages in a diary reduces the availability of contiguous space for writing longer entries, external fragmentation occurs when memory blocks are allocated and deallocated in a non-contiguous manner, leading to a lack of available memory for important tasks.