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prof. P.Cremonesi Esame Di Impianti 2012-07-11 - Soluzione Last name / Cognome First name / Nome Matricola Grade / Voto Exam duration: 2 hours If the exam is completed at least 15 minutes in advance, the student will receive one extra bonus of 1 point. If the exam is completed at least 30 minutes in advance, the student will receive one extra bonus of 2 points. If the exam is completed at least 45 minutes in advance, the student will receive one extra bonus of 3 points. If the exam is completed at least 60 minutes in advance, the student will receive one extra bonus of 4 points. Students can use pen or pencil to write answers. Please, do not write answers in red color. Students are permitted to use a non-programmable calculator. Students are NOT permitted to copy anyone else’s answers, pass notes amo ngst themselves, bring sheets, take the exam on behalf of someone else or engage in other forms of misconduct at any time during the exam. Violators shall receive a zero grade for the exam. Students are NOT permitted to use mobile phones and similar conn ected devices. If any of such devices will be discovered in the vicinity of a student, the student shall receive a zero grade for the exam. Question 1 Esame Di Impianti 2012-07-11 - Soluzione Score (3 punti) Performance By monitoring a single class iteractive system, we are able to measure the following data: - Monitoring period: 5 minutes <- not required - Disk utilization: 40% <- not required - CPU demand: 0,3 seconds/transaction - CPU utilization: 30% - Response time: 10 seconds/transaction - Number of users: 60 Which is the average think time of these users? Throughput 1 transactions/second Think time 50 Question 2 Esame Di Impianti 2012-07-11 - Soluzione Score (3 punti) Performance Consider the following measurement…