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DRAFT y +1/1/60+ y Student ID (Matricola) 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 Computing Infrastructures Course 095897 M. Gribaudo, R.Mirandola 30-06-2016 Last Name / Cognome: ................................................................. First Name / Nome: ................................................................. Answers must be given exclusively on the answer sheet (last sheet): DO NOT FILL ANY BOX IN THIS SHEET Students must use pen (black or blue) to mark answers (no pencil). Students are permitted to use a non-programmable calculator. Students are NOT permitted to copy anyone else’s answers, pass notes amongst themselves, or engage in other forms of misconduct at any time during the exam. Students are NOT permitted to use mobile phones and similar connected devices. Scores for the multiple-choice part: correct answers +1 point, unanswered questions 0 points, wrong answers -0.333 points. You cannot keep a copy of the exam when you leave the room. y For your examination, preferably print documents compiled from auto-multiple-choice. y DRAFT y +1/2/59+ y Disks Consider the following set of disks connected in RAID 6, with generatorg = 2: !"#$%& !"#$%' !"#$%( !"#$%) !"#$%* !"#$%+ !, , !& * !' & !( ( - . / (0 !, & !& & !' & - * / '( !( ' 1234$%1& 1234$%1' 1234$%1( 1234$%1) 1234$%1* 1234$%1+ 1234$%5& 1234$%5' 1234$%5( 1234$%5) 1234$%5* 1234$%5+ Figure 1: A RAID 6 configuration. Question 1 What data is contained in blocksA5 and A6? A P = 9, Q = 76 B P = 9, Q = 38 C Cannot be computed D P = 9, Q = 9 SOLUTION: P = 0 + 5 + 1 + 3 = 9 , Q = 0 + 5· 2 + 1· 4 + 3· 8 = 10 + 4 + 24 = 38 Question 2 What data is contained in blocksB3 and B6? A D2 = 1, D3 = 2 B D2 = 0, Q = 3 C Cannot be…