Difference Between Paging and Swapping in OS

Both paging and swapping are important concepts in operating systems that place a process in the main memory for its execution, but they are quite different from each other in many aspects. Read this article to learn more about paging and swapping and their specific characteristics.

What is Paging?

In OS, Paging is a memory management strategy in which the process address space is divided into blocks of the same size, called pages (where the size of each page is power of 2, and is between 512 bytes and 8192 bytes). The size of the process is then measured in the number of pages.

In the same way, the main memory is divided into small blocks of fixed size called frames. The size of each frame is kept the same as that of a page to have the optimum utilization of the main memory and to avoid the external fragmentation. Therefore, paging is basically a memory allocation technique. It utilizes non-contiguous memory management technique.

What is Swapping?

Swapping is a memory management technique in which an entire process is copied to another location. In other words, swapping is a technique in which an entire process is to be placed in the main memory for its execution. Also, swapping removes the inactive processes from the main memory of the system.

Swapping helps to provide memory space for the operation of other processes. Hence, swapping impacts the performance of a system, as it helps in executing multiple large operations concurrently. Swapping can be done without using any memory management technique.

Now, let us discuss the differences between paging and swapping in detail.

Difference between Paging and Swapping in OS

The following are the important differences between paging and swapping in Os −

S.No.	Swapping	Paging
1.	It is process where the entire process is copied to another location.	It is a memory allocation technique.
2.	This process occurs when the entire process has been transferred to the disk.	This process occurs when a part of a process is transferred to the disk.
3.	Here, the data is swapped temporarily from the main memory to a secondary memory.	The contiguous block of memory is made non-contiguous but it consists of fixed size called frames known as pages.
4.	It can be done without using any memory management methods.	It uses non-contiguous memory management technique.
5.	It can be done by processes that are inactive as well.	Only a process that is currently active can perform paging operation.
6.	It helps give a direction with respect to the solution.	There is no suggestion about the solution in this technique.

Conclusion

The most significant difference between the two is that swapping is a process where the entire process is copied to another location, while paging is a memory allocation technique.