Question 3 (25 points) A file server with a CPU and two disks, 1 and 2, is modeled as in this figure: Exit Enter alla 112 Disk 1 CPU ILO Disk 2 Measurements produced the following data: o Observation interval = 3000 seconds Number of client requests = 12000 requests O CPU busy time = 1200 seconds o Disk A busy time = 1600 seconds o Disk B busy time = 120 seconds o Total number of visits to CPU = 60000 o Total number of visits (I/O requests) to disk 1 = 36000 o Total number of visits (I/O requests) to disk 2 = 12000 a) (10 points) Calculate overall throughput and number of visits to each device per client request. b) (6 points) For each device, calculate average service time per request. c) (9 points) Calculate device utilizations and determine which device is the bottleneck. Question 3 (25 points) A file server with a CPU and two disks, 1 and 2, is modeled as in this figure: Exit Enter alla 112 Disk 1 CPU ILO Disk 2 Measurements produced the following data: o Observation interval = 3000 seconds Number of client requests = 12000 requests O CPU busy time = 1200 seconds o Disk A busy time = 1600 seconds o Disk B busy time = 120 seconds o Total number of visits to CPU = 60000 o Total number of visits (I/O requests) to disk 1 = 36000 o Total number of visits (I/O requests) to disk 2 = 12000 a) (10 points) Calculate overall throughput and number of visits to each device per client request. b) (6 points) For each device, calculate average service time per request. c) (9 points) Calculate device utilizations and determine which device is the bottleneck