Well, I'm doing the Operating Systems discipline, and there's been some doubt as I read memory management.
From what I have read, one way to abstract memory is to use base and limit registers, where for each program in physical memory its start is stored in the base register and the end in the limit. Goodbye. Then I saw ways to manage free memory, which is what to do when taking or allocating a program in physical memory, hence has the bitmap or by list chained, in case the list chained has the algorithms first-fit, next-fit , best-fit, worst-fit. Until then, OK.
So I've understood so far that it takes an abstraction of memory for many programs to use and a way to manage available space, such as allocate and etc.
Now I'm seeing virtual memory, which I understand is when the program does not fit into physical memory and you need to execute it even if it is not in memory. Then use the pagination scheme and page table, which when you need to fetch some instruction in memory the MMU ( Memory Management Unity ) calculates the absolute address through the page frame that this reference page and its displacement.
Now that my question comes in, when using paging, does not it use the base register scheme and limit? Because every process will be stored in the pages and the MMU does the calculation for absolute address no longer needs to register base and limit.