List of top Operating System Questions on Memory Management and Virtual Memory asked in GATE CS

A system has a Translation Lookaside Buffer (TLB) that has a reach of \(1\) MB. TLB reach is defined as the total amount of physical memory that can be accessed through the TLB entries. The paging system uses pages of size \(4\) KB. The virtual address space is \(64\) GB and physical address space is \(1\) GB. If each TLB entry stores a \(4\)-bit process id, page number, frame number, and a \(2\)-bit control field, then the size of the TLB (in bytes) is ______. (answer in integer)

Note: \(1K=2^{10}\), \(1M=2^{20}\), \(1G=2^{30}\)

Consider contiguous allocation of physical memory to processes using variable partitioning scheme. Suppose there are 8 holes in the memory of sizes 20 KB, 4 KB, 25 KB, 18 KB, 7 KB, 9 KB, 15 KB, and 12 KB. Assume that no two holes are adjacent. Two processes P1 of size 16 KB and P2 of size 9 KB arrive in that order, and they are allocated memory using the best-fit technique. After allocating space to P1 and P2, the number of holes of size less than 8 KB is ______.

Note: \(1\text{K}=2^{10}\)

Which one of the following statements is FALSE?

Consider a demand paging system with four page frames (initially empty) and LRU page replacement policy. For the following page reference string: \[ 7, 2, 7, 3, 2, 5, 3, 4, 6, 7, 1, 5, 6, 1 \] The page fault rate, defined as the ratio of the number of page faults to the number of memory accesses (rounded off to one decimal place) is \(\underline{\hspace{1cm}}\).