需求分页和分段的区别

需求分页：
请求寻呼与带交换的寻呼系统相同。在按需分页中，页面被按需传送到内存中，即，仅当对该页面上的某个位置进行引用时。按需分页结合了简单分页的特点，并实现了虚拟内存，因为它具有较大的虚拟内存。延迟交换器概念在按需分页中实现，其中除非需要，否则页面不会交换到内存中。

分割：
分段是内存管理的安排。根据分段，逻辑地址空间是分段的集合。每个段都有一个名称和长度。每个逻辑地址有两个数量段名和段偏移量，为简单起见，我们使用段号代替段名。

Demand Paging 和 Segmentation 的区别如下：

S.No.	Demand Paging	Segmentation
1.	In demand paging, the pages are of equal size.	While in segmentation, segments can be of different size.
2.	Page size is fixed in the demand paging.	Segment size may vary in segmentation as it grants dynamic increase of segments.
3.	It does not allows sharing of the pages.	While segments can be shared in segmentation.
4.	In demand paging, on demand pages are loaded in the memory.	In segmentation, during compilation segments are allocated to the program.
5.	Page map table in demand paging manages record of pages in memory.	Segment map table in segmentation demonstrates every segment address in the memory.
6.	It provides large virtual memory and have more efficient use of memory.	It provides virtual memory and maximum size of segment is defined by the size of memory.