Solved-Assignment 10- Solution

Description

1. 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)

2. 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

3. 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

4. How can processors defend against the Meltdown attack? (10 points)