title: How is it decided how much of virtual address space is mapped in page table?
body: <p>I have read that Arm V7 ISA gives 4gig of virtual address space for a program. If i take a program in which all the code come within 4kilobyte, my question is whether entire 4gig of space is mapped in page table? I we take short descriptor format for building page tables and use a 4k granularity, it will take a lot of space in the ram to hold the page table. So i think the whole 4GB of space for a single process is not mapped but only a part of it is mapped. Is this correct? If it is correct then how is it decided how much of the VA is mapped in the tables?</p>