Potpourri The context for this question is the same as the previous question. Figure shows I/O is virtualized in Cellular-Disco.  [2 points] What does CD do in step 5 and why?

Paravirtualization The context for this question is the same as the previous question. Above picture shows the I/O ring data structure used in Xen to facilitate communication between the guest OS and Xen.  Guest-OS places a request in the I/O ring using the “Request Producer” pointer. Xen places a response in the I/O ring using the “Response Producer” pointer.  [2 points] You are implementing disk I/O in a guest OS using Xen’s I/O ring. What steps are needed to achieve zero-copy semantics for a block write?

Full Virtualization [2 points] “Physical memory is an illusion of the guest OS in a fully virtualized environment”. Explain what this means.

Muscle, bone, water, and organs are all considered components of fat-free mass.

Lock/Barriers Consider Anderson’s array-based queuing lock shown pictorially below, where N is the number of processors.  One disadvantage of this algorithm is that the size of the array has to be as big as the number of processors.  An alternative is to use a dynamic array wherein the array can be grown based on the number of simultaneous lock requestors. [3 points] Give one advantage and one disadvantage of this idea compared to the MCS lock algorithm that uses a linked list to implement the lock as opposed to an array. 

　 Rating 1 Rating 2 Rating 3 Rating 4 Rating 5 Male 12 14 29 69 26 Female 0 4 7 23 16 According to the contingency table, how many females gave a satisfaction rating of 4?

Satisfaction Frequency Relative Frequency Percent Frequency 1 12 0.06 6 2 18 0.09 9 3 36 0.18 18 4 92 0.46 46 5 42 0.21 21 Using the satisfaction frequency table, what percentage of customers gave a rating of 4?

Looking at the scatterplot of income vs. purchase, what type of relationship is observed?

Which definition best describes a computer’s MAC address?

A host in an organization has IP address 133.32.64.34 Identify the address class of the IP address. Answer format:  To receive the correct points for this problem, enter only the letter in the box. Class = [class] Example: For a class F IP address, enter F