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prof. P.Cremonesi Esame Di Impianti 2013-07-19 Soluzione.Docx Last name / Cognome First name / Nome Matricola Grade / Voto Exam duration: 1,5 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. 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 any one else’s answers, pass notes amongst 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 connected 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. Domanda 1 Esame Di Impianti 2013-07-19 Soluzione.Docx Score (2 punti) Performance By monitoring a single class interactive system, we are able to measure the following data: - Disk demand 0,4 seconds/transaction - CPU demand: 0,6 seconds/transaction - CPU utilization: 30% - Monitoring period: 8 minutes - Response time: 20 seconds/transaction - Number of users: 16 Which is the average think time of these users? Z = N/X - R Ucpu = Dcpu X X = Ucpu / Dcpu = 0.3 / 0.6 transactions/s = 0.5 transaction/s Z = 16 / 0.5 s - 20 s = 12 s Domanda 2 Esame Di Impianti 2013-07-19 Soluzione.Docx Score (2 punti) Performance Consider a multi station system with two stations. We have the following information about the system: - station 1 response time: 4 seconds - station 2 response time: 1 seconds - station 1…