What is an inverted page table? Why are inverted page tables used? Explain how an inverted page table is used to service a TLB-miss fault in an operating system running on a CPU with software-based TLB refill.
Explain why an exact LRU (least recently used) replacement policy can be used for managing the physical memory resources of a file system buffer cache but not the physical memory resources of a virtual memory system.
Why do operating systems provide system calls to open and close files, as opposed to simply incorporating the same functionality into the read and write system calls?