I HC QUC GIA TP

Trng i hc Cng ngh Thng Tin

Khoa K thut My tnh

THI MN H IU HNH

THI GIAN LM BI : 120 PHT

(Sinh vin c php tham kho ti liu , cn b coi thi khng gii thch g thm)

1.(a) Supervisor hay Kernel mode l g ? User mode l g ? Cho bit s khc nhau gia chng? (1)

(b) Lit k nhng s khc nhau chnh gia kernel-supported threads v user-level threads ? (1)

(c) V lc trng thi ca tin trnh t lc chng c to ra cho n lc kt thc , bao gm tt c nhng chuyn tip mi trng thi v mi s chuyn tip. (1)

(d) Context l g ? Hy m t chi tit tt c nhng hot ng trong mt context switch. (1)

2. (a)Ti sao nh thi CPU first-come-first-served v shortest-job-first c xem l trng hp c bit ca priority based scheduling ? Vn chnh trong nh thi priority based scheduling l g v cch gii quyt cho vn ny l g ? (1)

(b)Phn mnh ni (internal fragment) v phn mnh ngoi (external fragment) l g ? Xt cc cch qun l b nh : fixed-size partitions, variable-size partitions, v paging cch qun l no cho phn mnh ni , phn mnh ngoi ? Ti sao ? (1)

3. Cho h thng nh sau :

H thng c oan ton khng ? Ti sao ? (1)

4. (a)Cho cc vng nh 100K, 500K, 200K,300K v 600K theo th t, cc gii thut first-fit, best-fit v worst-fix s ch nh cc vng nh cho cc tin trnh 310K, 80K, 350K v 230K (theo th t) nh th no ? (1)(b)Cho h thng demand paging vi 4 frames v chui tham chiu nh sau vi 7 trang:

Gi s b nh ban u l trng, cho bit qu trnh thay th trang nh vi cc gii thut thay trang

(i) FIFO (1)

(ii) LRU (1)--HTTrng i hc Cng ngh Thng Tin

Khoa K thut My tnh

THI MN H IU HNH

THI GIAN LM BI : 120 PHT

(Sinh vin c php tham kho ti liu , cn b coi thi khng gii thch g thm)

1. (a) Cho bit cc trng thi ca tin trnh (process) v m t c im ca nhng trng thi ? (0,25)

(b)Thread l g ? Cho bit ch li ca vic s dng thread ? (0,25)

(c) Race condition l g ? cho bit cch chng ta c th trnh race condition ? (0,25)

(d) Anh/ch hiu th no v : virut , worm, trojan hourse ? (0,25)

2. (a) Cho bit s khc nhau gia user-level threads v kernel-level threads ? (0,5)

(b) Phn bit 2 khi nim : Buffer v Cache (0,5)

(c) Phn bit 2 khi nim : Virtual Memory v Paging (0,5) (d) Phn bit 2 kin trc a x l : Shared memory v Distributed System (0,5)

3. Cho 4 tin trnh , tt c cc tin trnh i vo theo th t ti thi im 0.Burst TimePriority (higher number =higher priority)

P161

P232

P3123

P444

V s Gannt v tnh thi gian ch trung bnh v thi gian xoay vng trung bnh cho cc gii thut nh thi

(a) First Come First Serve(FCFS) (1)(b) Shortest Remaining Time First (SRTF) (1)(c) Priority based scheduling (nh thi da trn u tin , vi lu s u tin cng cao th u tin cng cao) (1)(d) Round Robin (RR) vi quantum = 3 (1)4. Gi s c 16 virtual pages v 4 frames voi cac so (0,4,2,1). Xc nh qu trnh thay th trang nh s sy ra i vi chui tham chiu nh sau :

khi s dng nhng gii thut thay th trang sau :

(a)FIFO (1)

(b)RLU ( 1)

(c) Optimal (1)

--HT--