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Danh mc cu hi v Hng dn cho im thi mn hcL THUYT H IU HNH
Phn 1: L thuyt
Cu 1: ngha ca System Call. Hy gii thch bnh thng cc phn mm ng
dngkhai thc phn cng ca my nh th no?Cu 2: Mt tin trnh yu cu H iu hnh
chuyn trng thi cho n ng 5 giy. Hiu hnh c m bo c l s kch hot tin
trnh ny ng 5 giy sau khng? Tisao?
Cu 3: Nu nh ngha H iu hnh. H iu hnh thc hin nhng chc nng
chnhg?
Cu 4: Multi-tasking l g? Gii thch s khc nhau gia cc hnh thc
Multi-tasking(cooperative and pre-emtive multi-tasking).Cu 5: S
ging nhau v khc nhau gia Chng trnh, Tin trnh v Lung
(Program,Process and Thread).Cu 6: So snh u v nhc im gia H iu hnh
client-server v h iu hnh nkhi (monolithic) truyn thng.
Cu 7: Hy gii thch c ch CPU chuyn t vic thc hin process ny sang
process khc.Lm sao c th m bo c vic thc hin ng cc lnh ca process tng
ng?Cu 8: Mc ch v nguyn tc ca vic lp lch cho CPU (Process
Scheduling)
Cu 9: ngha cn bn ca Lp lch, S khc nhau gia Lp lch di k v lp lch
ngnhn?Cu 10: Gii thiu s lc 5 cch la chn tin trnh t ready to run thc
hin. nhgi thut ton FCFSCu 11: Gii thiu s lc 5 cch la chn tin trnh t
ready to run thc hin. nhgi thut ton SJFCu 12: Gii thiu s lc 5 cch
la chn tin trnh t ready to run thc hin. nhgi thut ton SRFCu 13: Gii
thiu s lc 5 cch la chn tin trnh t ready to run thc hin. nhgi thut
ton RRCu 14: Gii thch ti sao phn a ch cao (top-half) ca h iu hnh
khng phi l tintrnh (process). Gii thch ti sao phn a ch thp
(bottom-half) ca h iu hnh cngkhng phi l tin trnh (process).Cu 15:
Gii thch ngn gn trng thi ca cc tin trnh, cc m hnh tin trnh h
thng(process models) chung.Cu 16: Gii thch vai tr ca PCB (process
control block).Cu 17: Gii thiu v gii thch ngn gn cc thnh phn
(components) ca H iu hnh.Cu 18:Nu vn tt cc k thut cp pht b nh (np
chng trnh vo b nh).Cu 19. Trong k thut cp pht b nh phn vng ng, khi
np tin trnh mi vo bnh cn la chn mt vng cn rng no . Nu cc phng
php/thut ton la chn.Cu 20: Phn tch hai khi nim Page v Paging (trang
v phn trang).
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Cu 21: Gi thch c ch phn on (segmentation) trong qun l b nh ca h
iuhnh.Cu 22: M t ngn gn B nh o Virtual memory. B nh o c li v thit
hi gi vi vic ti u ho s dng CPU.
Cu 23: Trong k thut b nh o thng s dng Phn trang theo yu cu
(demand
paging). Hy gii thiu c ch ny.Cu 24: Trong k thut s dng B nh o H
iu hnh cn c b phn qun l vic honchuyn cc trang/on gia b nh thc v b
nh o v c th xy ra Li trang (pagefault). H iu hnh gi quyt vn nh th
no v mc tiu cn t c?Cu 25: nh gi cc thut ton thay trang (Page
Replacement) trong k thut s dng Bnh o.
Cu 26: Nu ngn gn cc thut ton Thay th trang trong k thut b nh o,
Trnh byv gii thch bng v d thut ton FIFO.
Cu 27: Nu ngn gn cc thut ton Thay th trang trong k thut b nh o,
Trnh byv gii thch bng v d thut ton Ti u OPT.
Cu 28: Nu ngn gn cc thut ton Thay th trang trong k thut b nh o,
Trnh byv gii thch bng v d thut ton LRU.
Cu 29: Phn bit hai hin tng phn mnh ni (internal fragmentation) v
phn mnhngoi (external fragmentation), chng xut hin khi no v ti
sao?
Cu 30: Gii thch khi nim hon chuyn (swapping); ngha, ng dng ca
vic pdng k thut ny.
Cu 31: Hy gii thch v sao DMA thng c u i s dng nh l phng thc
thcthi trao i vi ngoi vi? DMA c li im g khng i vi input thng qua bn
phm?Gii thch ti sao hoc ti sao khng?Cu 32: Cc my tnh nguyn chic s
dng ph bin hin nay thng ci t H iuhnh Windows XP hoc Vista; y l cc h
thng/ H iu hnh a trnh a nhim. Hygii thiu mt s dng h thng/ h iu hnh
khc.Cu 33: Khi hc mn Tin hc i cng chng ta c bit n mt cch chia
ccthit b ngoi vi thnh 2 hoc 3 loi (nhm) l VO, RA v/hoc va VO va
RA;Di gc nhn ngi thit k H iu hnh chng ta c th chia thit b ngoi vi
thnh 2loi. l g v cch chia ny da trn cn c no? Hy nu v d mt s ngai vi
thuctng loi trn.Cu 34: Gii thch s khc bit gia polled I/O v
interrupt-driven I/O. Nu nhng uim ca interrup-driven I/O so vi
polled I/O.Cu 35: Mt cch tng i, a cng chm hn rt nhiu so vi CPU. Nu
cc yu tnh gi tc truy xut d liu trn a. Hy nu ngn gn cc k thut m H iu
hnhs dng nng cao thng lng (throughput) trung bnh ca a.Cu 36: Hy gii
thch thut ton Lp lch cho u t FCFS l g, cho v d m t tnh c seek
time.
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Cu 37: Hy gii thch thut ton Lp lch cho u t SSTF l g, cho v d m t
tnh c seek time.Cu 38: Hy gii thch thut ton Lp lch cho u t SCAN l
g, cho v d m t tnh c seek time.Cu 39: Hy gii thch thut ton Lp lch
cho u t C-SCAN l g, cho v d m t
tnh c seek time.Cu 40: Hy gii thch thut ton Lp lch cho u t
C-LOOK l g, cho v d m t tnh c seek time.Cu 41: C 2 dng thit b u cui
ni tip (serial) v memory-mapped u y k t ramn hnh. Hy gii thch ti
sao thit b u cui ni tip phi s dng ngt trong khi thitb u cui
memory-mapped khng bt buc.Cu 42: Tc nghn (deadlock) v cc iu kin xy
ra tc nghn.Cu 43: Nguyn tc/ phng thc chung nng cao hiu nng ca h
thng.Cu 44: nh gi ngn gn cc loi thit b lu tr; s khc nhau cn bn gia
a cngv Bng t; Nguyn tc t chc lu tr tp tin trn 2 loi thit b lu tr
ny.Cu 45: Cc thuc tnh chnh v cc trng thi ca File cc h iu hnh khc
nhau thng
c?Cu 46: Gii thiu cu trc th mc trong vic t chc lu tr tp tin trn
a.Cu 47: Cc phng php c s dng qun l, cp pht cc block a cho cc
File.Cu 48: Ti sao ta c th ni H iu hnh thc hin Vo/Ra. Hy gii thch c
chChng trnh ng dng thc hin I/O nh th no?Cu 49: Phn bit Device,
Driver v Device Controller.Cu 50: Gii thch khi nim on gng (Critical
Section). Nu ngn gn bin php giiphp iu phi tin trnh qua on gng.
- Phn 2: Bi Tp
Cu 1: C yu cu truy nhp a gi ti a cng i vi cc cylinder s 10, 92,
20, 53,
77, 45, 6 v 38 vi trnh t nh trn.Thi gian dch chuyn u t t
cylinder ny sang cylinder k tip l 5 mili giy. Tng sthi gian tn dch
chuyn u t l bao nhiu cho mi phng php di y?
a) FCFSb) SSFc) SCANd) C-SCANe) C-LOOK
i vi tt c cc trng hp trn, u t bt u t cylinder s 40 trong khi a
cng c100 cylinder, v i vi SCAN, C-SCAN v C-LOOK u t ang dch chuyn
theo chiutng ca s cylinder (dch vo pha tm ca a).
(Ch : D liu c th c cung cp hay chn ngu nhin t my tnh khi nhn
thi)
- V ng, nu ng trnh t cho tng mi phng php (1 *5)- Tnh ng cho mi
phng php (1 * 5)
Cu 2: My tnh s dng partition qun l b nh, v ti mt thi im b nh vt
lca my ang c s dng nh sau:
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Cu 6: C cc tin trnh P0, P1, P2, P3 v P4 ang sn sng ch c cp pht
CPU.nh gi cc thut ton la chn tin trnh cp pht (thut ton lp lch cho
CPU). Cctin trnh c thi gian cn CPU (CPU burst time) v c thi gian n
(vo hng i Ready)c cho trong bng di y:
Tin trnh Thi gian n (ms) CPU burst Time (ms)P0 0 25P1 8 15P2 8
2P3 10 50P4 25 1i vi m hnh Time-sharing, Quantum time hay Time
slice = 10ms(Ch : D liu c th c cung cp hay chn ngu nhin t my tnh
khi nhn thi)
- Gii thch v tnh ng cho mi thut ton: 2,5 X 4- Trnh by ng nhng th
hin sai tr 1 im cho mi thut ton nhm
Cu 7: Trong cc h thng p dng k thut B nh o, mi tin trnh c cp pht
hnch s lng khung trang trong khi s lng trang thc t tin trnh yu cu c
th nhiuhn nhiu. Hy gii thch ngn gn cc thut ton Thay th trang v tnh
s lng litrang vi mi thut ton tng ng i vi Tin trnh c yu cu truy nhp
theo trnh tcc trang sau: 1, 2, 3, 4, 5, 7, 8, 9 , 2, 3, 4, 7, 1, 2,
3, 8, 4, 8, 5, 6, 7, 1 vi trng hp skhung trang c cp l 4.(Ch : D liu
c th c cung cp hay chn ngu nhin t my tnh khi nhn thi)
- Gii thch v tnh ng cho mi thut ton thay th trang: 2,5 X 4
- Trnh by ng nhng th hin sai tr 1 im cho mi thut ton nhmCu 8: C
yu cu truy nhp a gi ti a cng i vi cc cylinder s 15, 45, 20, 33,77,
45, 6 v 38 vi trnh t nh trn.Thi gian dch chuyn u t t cylinder ny
sang cylinder k tip l 5 mili giy. Tng sthi gian tn dch chuyn u t l
bao nhiu cho mi phng php di y?
f) FCFSg) SSFh) SCANi) C-SCANj) C-LOOK
i vi tt c cc trng hp trn, u t bt u t cylinder s 40 trong khi a
cng c100 cylinder, v i vi SCAN, C-SCAN v C-LOOK u t ang dch chuyn
theo chiutng ca s cylinder (dch vo pha tm ca a).(Ch : D liu c th c
cung cp hay chn ngu nhin t my tnh khi nhn thi)
- Gii thch ng mi thut ton: 1 X 3- V ng v tnh ng cho mi thut ton:
(1 + 1) * 3- R rng, chnh xc: 1
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Cu 9: C cc tin trnh P0, P1, P2, P3 v P4 ang sn sng ch c cp pht
CPU.nh gi cc thut ton la chn tin trnh cp pht (thut ton lp lch cho
CPU). Cctin trnh c thi gian cn CPU (CPU burst time) v c thi gian n
(vo hng i Ready)
c cho trong bng di y:
Tin trnh Thi gian n (ms) CPU burst Time (ms)P0 0 15P1 2 25P2 10
48P3 10 5P4 25 22i vi m hnh Time-sharing, Quantum time hay Time
slice = 10ms(Ch : D liu c th c cung cp hay chn ngu nhin t my tnh
khi nhn thi)
- Gii thch v tnh ng cho mi thut ton: 2,5 X 4- Trnh by ng nhng th
hin sai tr 1 im cho mi thut ton nhm
Cu 10: Trong cc h thng p dng k thut B nh o, mi tin trnh c cp pht
hnch s lng khung trang trong khi s lng trang thc t tin trnh yu cu c
th nhiuhn nhiu. Hy gii thch ngn gn cc thut ton Thay th trang v tnh
s lng litrang vi mi thut ton tng ng i vi Tin trnh c yu cu truy nhp
theo trnh tcc trang sau: 1, 2, 3, 6, 7, 1, 8, 3, 4, 5, 7, 8, 1, 2,
3, 8, 9, 1, 4, 5, 6, 7,1 vi trng hp ccp 4 khung trang.(Ch : D liu c
th c cung cp hay chn ngu nhin t my tnh khi nhn thi)
- Gii thch v tnh ng cho mi thut ton thay th trang: 2,5 X 4- Trnh
by ng nhng th hin sai tr 1 im cho mi thut ton nhm
