Consider a processor that uses 32-bit virtual addresses and a 36-bit physical address. Assume that the system uses 4KB pages.
What is the size of a program's virtual memory? (5 points)
What is the size of the system's physical memory? (5 points)
How many virtual pages does a program have? (5 points)
How many physical pages does the system have? (5 points)
Consider a 3-processor multiprocessor connected with a shared bus that has the following properties: (i) centralized shared memory accessible with the bus, (ii) snooping-based MSI cache coherence protocol, (iii) write-invalidate policy. Also assume that the caches have a writeback policy. Initially, the caches all have invalid data. The processors issue the following five requests, one after the other. Create a table similar to that in slide 6 of lecture 25 to indicate what happens for every request. (35 points)
P1: Read X
P1: Write X
P3: Read X
P2: Read X
P3: Write X
Consider a 3-processor multiprocessor connected with a scalable network that has the following properties: (i) distributed memory organization, (ii) directory-based cache coherence protocol, (iii) write-invalidate policy. Also assume that the caches have a writeback policy. Initially, the caches all have invalid data. Assume that data X is stored in the memory connected to processor P2. Create a table similar to that in slide 13 of lecture 25 to indicate what happens for every request. (35 points)
P1: Read X
P1: Write X
P3: Read X
P2: Read X
P3: Write X
How can processors defend against the Meltdown attack? (10 points)
