operating system - Why is limit Register needed in Page based memory management? -

Using the border register, we can know the length of the segment from the base.

But the page-based memory management, the size of each page is fixed and not connected to the RAM (as the frame), so here is the requirement for border registration ??

It is no longer used in the new CPU.

Segmentation in modern systems is set to flat mode only (the base is 0x0, end of border memory), so basically the whole memory is in a segment.

It is for legacy purposes, mostly like real mode.