according to the problem description of Assignment 3, NRU is to be implemented with “a reasonable clock tick”. Does that mean we are to apply the clock algorithm?
No, it means you pick a reasonable time interval in between times when you clear all the “referenced” bits. • I was wondering what the number of ticks should be before we change pages from recently used to not recently used. Could you give me a ballpark range? No, it’s up to you. If you don’t know a good range, do some experiments. • To implement Perfect LRU, we’d need hardware support (i.e., the hardware setting a timestamp on every reference), but the Nachos machine does not have this support. How do we do this without hardware support? You can timestamp the pages every time you load them into the TLB, instead of every time they are actually referenced. • Are we allowed to implement the LRU any way we want? In the Anderson notes it says that we should use a linked list (descending order based on age) but this seems unnecessary; I’d rather use an array instead. Yes, you can implement it however you like, including as an array. • In project 2, when a new address space was created, we i
