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N TP MN NL HH Cu 1. C 5 tin trnh P0, P1, P2 , P3, P4 v 4 kiu ti nguyn A, B, C, D. Ti thi im t, trang thi ca h thng nh sau: cp pht Cn ti a Cn

A B C D A B C D A B C D P0 2 0 0 1 4 2 1 2 3 3 2 1 P1 3 1 2 1 5 2 5 2 P2 2 1 0 3 2 3 1 6 P3 1 3 1 2 1 4 2 4 P4 1 4 3 2 3 6 6 5

a. V th phn phi ti nguyn cho h thng. b. H thng ang trng thi an ton hay khng an ton, gii thch. c. Liu yu cu (0, 2, 1, 0) ca P4 s c chp nhn ?

Cu 2. C 5 tin trnh P1, P2 , P3, P4, P5 vi thi gian chy CPU (ms), thi gian n v s hiu u tin nh sau:

Thi gian chy S hiu u tin Thi gian n P1 2 2 0 P2 1 1 1 P3 8 4 3 P4 4 2 4 P5 5 3 5

Vi mi thut ton lp lch sau hy v biu Gantt v tnh thi gian ch trung bnh, thi gian phn hi trung bnh, thi gian hon thnh trung bnh

a. Round Robin vi quantum = 2 (ms) b. SJF cho php dng c. Lp lch theo s hiu u tin (bit rng tin trnh c s hiu u tin cao hn s

c chy trc) Cu 3. C 5 tin trnh P1, P2 , P3, P4, P5 vi thi gian chy CPU (ms), thi gian n nh sau:

Thi gian chy Thi gian n P1 2 0 P2 6 1 P3 8 3 P4 3 4 P5 5 5

Vi mi thut ton lp lch sau hy v biu Gantt v tnh thi gian ch trung bnh, thi gian phn hi trung bnh, thi gian hon thnh trung bnh

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d. Round Robin vi quantum = 4 (ms) e. SJF khng cho php dng f. FCFS

Cu 4. Vi trnh t s dng cc trang nh sau : 7, 2, 3, 1, 2, 5, 3, 4, 6, 7, 7, 1, 0, 5, 4, 6, 2, 3, 0 , 1 Hy tnh s lng page fault khi cp pht cho tin trnh 3, 4, hoc 5 frame v s dng mt trong cc thut ton thay th trang sau:

a. FIFO b. Thut ton ti u c. LRU ( khng s dng lu nht)

Cu 5. V biu Gantt v tnh thi gian ch trung bnh, thi gian hon thnh trung bnh, thi gian phn hi trung bnh cho cc tin trnh khi s dng thut ton hng i a cp.

Hng i Tin trnh Thi gian chy Thi gian n Thut ton

n Hng i trc s 1 P1 50 0 RR P2 15 30 quantum=20

P3 45 30

n Hng i trc s 2 P4 40 0 SJF cho php P5 10 120 dng

n Hng i sau P6 30 60 FCFS P7 20 130

Bit rng trnh t u tin cc hng i nh sau: Hng i trc s 1, Hng i trc s 2, Hng i sau. Cu 6. H thng s dng 12 bit cho a ch o v a ch vt l, kch thc mi trang l 256 byte. Da vo bng phn trang sau: Page no. Frame no. 0 a. Tm a ch vt l tng ng cho cc a ch o sau (dng 1 2 hexa): 9EF, 700, 0FF 2 12 b. Tin trnh truy cp vo a ch no trong cc a ch o 5 trn s to ra page fault ? 3 10 c. Nu kch thc mi n v b nh l 4 byte, hy tnh 4 dung lng b nh chnh, s lng frame 5 4 6 3 7

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8 11 9 0 Cu 7. B nh o c nhng thng s sau:

Kch thc a ch o cho php nh s a ch cho 64 M phn on Kch thc ti a mi phn on 4 MB Kch thc b nh vt l 64 GB Bng phn on lu ti RAM Mi phn on c bit xc nh quyn c v vit Kch thc mi n v b nh vt l l 16 byte

V s nh x a ch o sang a ch vt l. Ch m bo cc thng tin sau:

Cc thnh phn trong mi a ch Kch thc (s bit) ca mi thnh phn S lng hng ti a ca bng phn on Kch thc ti a ca bng phn on Kim tra li nu c

Cu 8. C 4 tin trnh P1, P2 , P3, P4 v 2 kiu ti nguyn A, B. Ti thi im t, trng thi ca h thng nh sau: cp pht Yu cu

A B A B P1 1 3 1 2 P2 4 1 4 3 P3 1 2 1 7 P4 2 0 5 1

a. V biu phn phi ti nguyn cho cc tin trnh b. Dng thut ton nhn din b tc kim tra xem liu h thng c b tc trong

trng hp sau: i. H thng cn 1 n v ti nguyn A v 4 n v ti nguyn B

ii. H thng cn 2 n v ti nguyn A v 4 n v ti nguyn B Cu 9. a. cng ca my tnh c kch thc 128 GB, kch thc mi khi trn a l 8 KB.

Nu h iu hnh s dng FAT th dung lng b nh nh nht lu FAT l bao nhiu ? Gii thch.

b. H iu hnh s dng i-node qun l cc khi d liu ca tp tin. I-node ca mi tp tin cha s hiu ca 12 khi trc tip, 1 khi gin tip mt cp 1, 1 khi gin tip mt cp 2, 1 khi gin tip mt cp 3. Kch thc mi khi trn a l 4 KB, s hiu ca mi khi chim 4 byte.

i. Tnh kch thc ln nht ca tp tin ? ii. Cn bao nhiu khi trn cng cha c tp tin ny ?

(Gi nh rng cng lun ln cha c tp tin)

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Cu 10. a c 5000 trc rnh nh s t 0 n 4999. u c/ghi ang trc rnh 2150, n va p ng yu cu ti trc rnh 1085. Yu cu vo/ra cc khi d liu trn cc trc rnh (theo trnh t FIFO) nh sau: 2069, 1212, 2296, 2800, 544, 1618, 356, 1523, 4965, 3681 V s ng i ca u c/ghi v tnh tng qung ng di chuyn ca u c/ghi cho cc thut ton lp lch sau:

a. SCAN b. C-SCAN c. LOOK d. C-LOOK

Cu 11. a. Semaphore l g ? C nhng loi semaphore no ? Trnh by cch s dng

semaphore, s dng v d minh ho. b. Cho ba tin trnh sau: P1: P2: P3: Wait(mutex1) Wait (mutex1) Wait (mutex2) Wait (mutex2) Wait (mutex2) Wait (mutex1) Signal(mutex1) Signal (mutex2) Signal (mutex1) Signal (mutex2) Signal (mutex1) Signal (mutex2)

i. a ra v d tnh hung xy ra b tc, ch r tin trnh no trong b tc. ii. Nu ch c tin trnh P1 v P2. a ra v d tnh hung xy ra b tc, ch r tin

trnh no trong b tc. Cu 12. C mt ci cu bc qua mt dng sng y c su. gia cu c mt chng cc thi vng. Cch duy nht ly c cc thi vng l i qua mt ci cng, i ln cu, nht thi vng v quay tr li cng. Ban u cng m, nu mt ngi bc ln cu m khng c ai khc gi cng th cng s b ng th ngi s b cht i cht cu. Nu c hai ngi trn cu cng mt lc th cu s gy v c su s khng b i. Sau khi ngi cui cng ly thi vng cui cng th nhng ngi cn li khng nn bc ln cu. S dng cc hm nguyn t sau:

start_holding_gate () // bt u gi cng stop_holding_gate ()// kt thc gi cng cross_bridge_and_get_gold ()// ln cu v ly vng, gi tr tr v l TRUE nu cn vng trn cu

Vit hm thc hin nhim v ly vng ca mi ngi sao cho: mi ngi n u ly c mt thi vng cho n khi ht vng v khng ai phi ch i mi mi. S dng semaphore trnh hin tng tranh chp.

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Cu 13. a. M t nguyn tc hot ng ca h thng Buddy. Phn tch cc u im v nhc

im ca h thng ny. b. H iu hnh c 256 KB b nh trong, ban u trng hon ton. Cc tin trnh yu

cu s dng b nh vi kch thc 5 KB, 25 KB, 35 KB, 20 KB. i. Hy m t cch h thng Buddy p ng mi yu cu, v s b nh tng

ng. ii. Sau khi cp pht ht cc yu cu trn, h thng s lm g nu tin trnh vi yu

cu b nh 25 KB kt thc v gii phng b nh ? Cu 14. a. V s , trnh by nguyn tc hot ng ca DMA (Direct Memory Access) b. Mt cng c cc thng s sau:

Thi gian tm kim track trung bnh 10 ms, thi gian tm kim track lin k 2 ms Tc trc quay (RPM): 800 S lng sector mi track l 10 S byte mi sector l 4096

Tnh tc truyn d liu. Cu 15. nh x b nh o 1 GB ln b nh vt l c 256 frame, mi frame c kch thc 4 KB. Kch thc mi n v b nh l 1 byte.

a. Liu b nh trong cha c ton b bng phn trang ? Gii thch. b. Liu bng phn trang nghch o cha c trong mt trang ? Gii thch

Cu 16. Mt tp tin c lu trn 100 khi. Gi nh rng khi iu khin tp tin (v cc khi ch mc nu c) u c chuyn vo b nh trong. Tnh s ln truy cp vo a :

a. Thm mt khi vo u tp tin b. Thm mt khi vo cui tp tin c. B mt khi u tp tin d. B mt khi cui tp tin

khi s dng phng thc cp pht lin tc, danh sch lin kt, v ch mc. Bit rng vi phng thc cp pht lin tc, ch c th m rng tp tin v pha cui tp tin. Thng tin ca cc khi thm vo c lu trong b nh.