Note: It is possible that these exams and/or quizzes cover things that we are not covering this semester, and/or that the keys posted are incorrect.

1 Summary

Semester	Exam	High	Median	Mean	Low	StdDev
Spring 2019	1	91.1%	80.6%	78.6%	54.8%	9.6%
Spring 2019	2	93.1%	77.8%	76.0%	52.2%	11.3%
Spring 2019	3	98.2%	85.3%	85.0%	60.1%	8.7%
Spring 2020	quizzes
Spring 2020	1 — not available —
Spring 2020	2
Spring 2020	3

2 Keys

2.1 Spring 2020

2.1.1 Exam 2

here

2.1.2 Exam 3

here

2.2 Spring 2019

2.2.1 Exam 1

Question	Key
Q1	2
Q2.1	False
Q2.2	True
Q2.3	True
Q2.4	True
Q2.5	True
Q2.6	False
Q2.7	False
Q3	STHRN
Q4	4
Q5	3
Q6	2
Q7	1
Q8	2
Q9	APM
Q10	1 or 2
Q11.1	True
Q11.2	True
Q11.3	True
Q11.4	False
Q11.5	True
Q11.6	True
Q12.1	True
Q12.2	True
Q12.3	(dropped)
Q12.4	False
Q12.5	True
Q13	2
Q14	45
Q15	266
Q16	0x22446400

2.2.2 Exam 2

Question	Key
Q1	(x>>(P+(P-3)*(L-1)))&((1<<(P-3))-1)
Q2	4
Q3	3
Q4	1
Q5	2
Q6	2
Q7	1
Q8	2
Q9	2
Q10	1
Q11	lock m1 between if and while; unlock m1 after primes[num_primes++] = i; and before next }
Q12	2
Q13	1 or 3 (can argue either way)
Q14	C(x, R(H(x)))
Q15	1
Q16	2
Q17	True True False True True False
Q18	0x1003F
Q19	False False True True

2.2.3 Exam 3

Question	Key
Q1	2
Q2.1	True
Q2.2	True
Q3	1
Q4	2
Q5	3
Q6	20,007
Q7	5
Q8	1
Q9	3 (1 also accepted)
Q10	5
Q11	1
Q12	Two deadlocks: a locked barrier (so either remove 1 and 3 or remove 2) and a barrier some threads run more often than others (so remove 4)
Q13	1
Q14	4
Q15	(dropped)
Q16.1	False
Q16.2	True
Q16.3	True
Q16.4	True – a non-signaling page-fault is handled by mapping a new page
Q16.5	True – new page access = new TLB entry
Q16.6	True – page faults are caused by memory accesses
Q17.1	True
Q17.2	True
Q17.3	True
Q17.4	True
Q17.5	True
Q17.6	False
Q18	1 – TLBs cache VA→PA mappings, not page tables, and only one new mapping here
Q19.1	False
Q19.2	True
Q19.3	True
Q19.4	True
Q19.5	False – this would work for Specter, but not Meltdown
Q20	29 = 512
Q21	58 – 2 more bits per VPN and 2 more for the PO too
Q22	4
Q23.1	True
Q23.2	True
Q23.3	False
Q23.4	True
Q24.1	False
Q24.2	False
Q24.3	True
Q24.4	False
Q25	512KB
Q26	3 (5 also accepted)
Q27.1	True
Q27.2	False
Q27.3	True
Q27.4	False
Q28.1	False
Q28.2	True
Q28.3	False
Q28.4	True
Q29.1	True
Q29.2	True
Q29.3	True
Q29.4	True
Q29.5	True – cannot have cycles without this
Q29.6	True – cannot have cycles without this
Q30.1	True
Q30.2	True
Q30.3	False
Q30.4	False – user account changes require kernel mode, meaning an exception
Q30.5	False
Q30.6	False
Q31.1	False
Q31.2	False
Q31.3	False
Q31.4	True
Q32	3