reason for logical address(virtaul address space) instead of physical address space

Question

I could understand the paging scheme. For every page (logical address + offset) , page frame is maintanined.

But what is the need of the paging? Executable program is loaded into RAM memory. why its need to be stored inform of page table(virtual address space)?

why physcial address space not used?

Answer 1

Physical address space is not used directly to provide an abstraction from the intricacies of a particular physical hardware. Virtual address space gives applications more memory than the physical memory chip can offer.

Virtual address space enables swapping of pages in and out of memory, so more applications can share the same physical memory, and you can also use your hard disk space as virtualized memory, though this is a bit slow, and can lead to thrashing.

With virtual address space, applications have the illusion of having the whole physical memory at their disposal, applications are isolated from each other and can't corrupt each other's memory.

Hope i helped...