Main memory size is 16 pages. Size of swap file on hard disk is 64 pages. Operating system locks down pages 0, 1, 2 and 7 in the main memory. Two programs are started and both are provided with a...

Main memory size is 16 pages. Size of swap file on hard disk is 64 pages. Operating system locks down pages 0, 1, 2 and 7 in the main memory. Two programs are started and both are provided with a virtual address space of 10 pages. Initially operating system allocates 5 pages of main memory for each program and the rest from swap file. Virtual address space of each program starts from page 0. Construct page tables for both programs at program startup. A page table consists of P-bit which tells if the page is present in the main memory (1 = page is in main memory) and address of the page. Address tells either real address in main memory or the address of the page in swap file. b. A computer with a paged virtual memory system executes two load instructions that are adjacent to each other in memory. Describe the worst case scenario (in terms of performance) that can occur during the execution of the two instructions and explain under which conditions this case occurs. How does this affect execution time of the program (make a rough estimate)?