Difference between Paging and Swapping
In this tutorial, we will be covering the differences between Paging and Swapping in Operating System.
Paging in OS
Paging is basically a technique of memory management in the operating system. In this technique, the operating system retrieves the processes from the secondary memory into the main memory and this memory is in the form of pages. Paging is a logical concept.
With the help of this technique, the main memory is split into the small blocks of physical memory that are commonly known as frames. In paging size of frames is fixed. In order to prevent external fragmentation and for the maximum usage of the main memory, the frame size must be the same as the page size. This technique helps to access the data faster.
Swapping in OS
Swapping is a memory management technique and is used to temporarily remove the inactive programs from the main memory of the computer system. Any process must be in the memory for its execution, but can be swapped temporarily out of memory to a backing store and then again brought back into the memory to complete its execution. Swapping is done so that other processes get memory for their execution.
Due to the swapping technique performance usually gets affected, but it also helps in running multiple and big processes in parallel. The swapping process is also known as a technique for memory compaction. Basically, low priority processes may be swapped out so that processes with a higher priority may be loaded and executed.
The above diagram shows swapping of two processes where the disk is used as a Backing store.
Difference Between Paging and Swapping
Let us cover the difference between Paging and Swapping in Operating System.
| Paging |
Swapping |
| Paging is a memory management technique in which computer stores and retrieves data from the secondary storage for use in the main memory. |
Swapping is a technique that is used to temporarily remove the inactive programs from the main memory of the computer system |
| This technique allows more processes to reside in the main memory |
Swapping allows fewer processes to reside in the main memory. |
| Paging follows non-contiguous memory management. |
Swapping can be done without any memory management technique. |
| Paging is more flexible because in this there is the movement of pages of a process. |
Swapping is less flexible as the entire process moves back and forth in the main memory and back store. |
| Paging occurs when some part of the process is transferred to the disk. |
While Swapping occurs when the whole process is transferred to the disk. |
| For medium workloads paging technique is suitable. |
For heavy workloads swapping technique is suitable. |
| This technique allows the memory address space of a process to be noncontiguous. |
With the help of Swapping multiple processes can run in parallel in the Operating System |
| This technique helps to implement virtual memory. |
Swapping helps the CPU to access processes faster. |
