17303 - Bai Giang Nguyen Ly He Dieu Hanh

7/30/2019 17303 - Bai Giang Nguyen Ly He Dieu Hanh

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B GIAO THNG VN TITRNG I HC HNG HI

B MN: K THUT MY TNHKHOA: CNG NGH THNG TIN

BI GINGNGUYN L H IU HNH

TN HC PHN : NGUYN L H IU HNHM HC PHN : 17303TRNH O TO : I HC CHNH QUY

DNG CHO SV NGNH : CNG NGH THNG TIN

HI PHNG - 2010


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MC LC

Chng I: NHNG KHI NIM C BN........................................................................... 61.1. Cu trc phn lp v h thng tnh ton....................................................................... 6

1.1.1. Cs ho h lnh ................................................................................................. 61.1.2. Tch thit b ngoi vi ra khi processor (micro ho procesor) ............................... 61.1.3. Chuyn nguyn tc Lnh thnh Menu ................................................................... 6

1.2. Ti nguyn h thng .................................................................................................... 71.2.1. B nh.................................................................................................................. 71.2.2. Thi gian thc hin lnh ....................................................................................... 81.2.3. Thit b ngoi vi ................................................................................................... 8

1.3. nh ngha h iu hnh .............................................................................................. 81.3.1. Vi ngi dng .................................................................................................... 81.3.2. Vi ngi qun l................................................................................................. 91.3.3. Vi cn b k thut............................................................................................... 91.3.4. Vi cn b lp trnh h thng................................................................................ 9

1.4. Phn loi h iu hnh ................................................................................................. 91.4.1. H iu hnh n nhim v h iu hnh a nhim............................................... 91.4.2. H iu hnh n Chng v h iu hnh a Chng (MultiUsers) .................... 91.4.3. H iu hnh tp trung v h iu hnh phn tn ................................................ 101.4.4. H iu hnh phn chia thi gian v h iu hnh thi gian thc ........................ 10

1.5. Tnh cht chung ca h iu hnh .............................................................................. 101.5.1. tin cy cao..................................................................................................... 101.5.2. an ton .......................................................................................................... 101.5.3. Hiu qu ............................................................................................................. 111.5.4. Tng qut ........................................................................................................... 111.5.5. Thun tin .......................................................................................................... 11

1.6. Nguyn tc xy dng h iu hnh ............................................................................ 111.6.1. Modul ................................................................................................................. 111.6.2. Nguyn tc tng i trong nh v..................................................................... 111.6.3. Macroprocessor .................................................................................................. 111.6.4. Ph chc nng .................................................................................................... 111.6.5. Gi tr chun (ngm nh): .................................................................................. 111.6.6. Tham s.............................................................................................................. 121.6.7. Nguyn l bo v................................................................................................ 12

1.7. Thnh phn h iu hnh ........................................................................................... 121.7.1. Thnh phn ca h iu hnh .............................................................................. 121.7.2. Thnh phn ca MSDOS .................................................................................... 12

Chng II: QUN L THIT B ........................................................................................ 142.1. Quan h phn cp trong t chc v qun l thit b ngoi vi....................................... 14

2.1.1. S a dng ca cc thit b ngoi vi: ................................................................... 142.1.2. Quan h gia vi x l vi thit b ngoi vi .......................................................... 142.1.3. Thc hin cc php vo/ra .................................................................................. 142.1.4. Kt thc chng trnh knh ................................................................................. 15


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2.2. Cch phng m (Buffer) ....................................................................................... 152.2.1. Phng m trung gian: ........................................................................................ 162.2.2. Phng m x l:................................................................................................ 162.2.3. Phng m vng ................................................................................................. 17

2.3. C ch SPOOL (Simultaneous Peripheral Operation On_Line - H thng m phngcc php trao i thit b ngoi vi trong ch trc tip).................................................. 172.4. Qun l file ............................................................................................................... 182.5. Qun l file trong h iu hnh MSDOS ................................................................... 19

2.5.1. Thit b c, ghi:................................................................................................. 192.5.2. Tham s a t:................................................................................................... 19

Chng III: QUN L B NH ........................................................................................ 283.1. t vn ................................................................................................................. 283.2. Qun l b nh logic - cu trc mt chng trnh ...................................................... 29

3.2.1. Cu trc tuyn tnh ............................................................................................. 293.2.2. Cu trc ng ..................................................................................................... 293.2.3. Cu trc Overlay................................................................................................. 293.2.4. Cu trc phn on ............................................................................................. 303.2.5. Cu trc phn trang............................................................................................. 30

3.3. Qun l b nh vt l ................................................................................................ 313.3.1. Phn chng c nh .......................................................................................... 313.3.2. Ch phn chng ng .................................................................................. 313.3.3. Ch phn on ............................................................................................... 323.3.4. Ch phn trang (nh x b nh logic thnh vt l).......................................... 333.3.5. Ch kt hp phn trang v phn on............................................................. 33

3.4. Qun l b nh IBM PC ca MSDOS ....................................................................... 34Chng IV: QUN L TIN TRNH ................................................................................. 36

4.1. Qun l tin trnh .............. ......................................... ......... ............. ......................... 364.1.1. Khi nim ........................................................................................................... 364.1.2. T chc tin trnh ................................................ ......................................... ...... 364.3.3. iu tin trnh - Ti nguyn Gng .................................................................. 374.1.4. Tnh trng tc nghn ........................................................................................... 404.1.5. Ngt (Interupt).................................................................................................... 42

4.2. Qun l Processor...................................................................................................... 434.2.1. Processor vt l v Processor logic ..................................................................... 434.2.2. Phn phi Processor............................................................................................ 444.3.3. iu tin trnh ............. ........................................ ........... ............ .................... 44

Chng V: H IU HNH NHIU PROCESSOR........................................................... 475.1. H iu hnh nhiu Processor.................................................................................... 47

5.1.1. Cu hnh nhiu Processor.................................................................................... 475.1.2. H iu hnh nhiu processor: ............................................................................ 47

5.2. H iu hnh phn tn (Distribute Operating System) ................................................ 485.2.1. Khi nim: .......................................................................................................... 485.2.2. c trng ca h iu hnh phn tn................................................................... 49

5.3. Qun l ti nguyn trong h iu hnh phn tn......................................................... 50


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5.3.1. Qun l thit b, qun l File............................................................................... 505.2.2. Qun l b nh................................................................................................... 515.2.3. Qun l tin trnh ............. ........................................ ........... ............ .................... 51


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YU CU V NI DUNG CHI TIT

Tn hc phn:Nguyn l H iu hnh Loi hc phn:1B mn ph trch ging dy:K thut my tnh Khoa ph trch:CNTTM hc phn: 17303 Tng s TC: 2

TS tit L thuyt Thc hnh/Xemina T hc Bi tp ln n mn hc

45 45 0 0 0 0

iu kin tin quyt:Sinh vin phi hc xong cc hc phn sau mi c ng k hc phn ny:Tin hc i cng, Kin trc my tnh, K thut lp trnh, Cu trc d liu, in t s,Mch v tn hiu

Mc tiu ca hc phn:- Cung cp cho sinh vin nhng khi nim tng quan v H iu hnh, cc phng phptip cn gii quyt cc bi ton iu khin hot ng ca h thng my.- Cung cp kin thc chung v nguyn l hot ng theo chng trnh trn h thngn, a b x l ca my tnh.

Ni dung ch yuChng I: Nhng khi nim c bn

Chng II: Qun l thit b

Chng III : Qun l b nhChng IV : Qun l tin trnh

Chng V : H iu hnh nhiu vi x l - h iu hnh phn tn

Ni dung chi tit ca hc phn:

TN CHNG MCPHN PHI S TIT

TS LT BT TH KT

Chng I: Nhng khi nim c bn 6 61.1. Cu trc phn lp v h thng tnh ton 1

1.2. Ti nguyn h thng 1

1.3. nh ngha h iu hnh 1

1.4. Tnh cht chung ca h iu hnh 1

1.5. Thnh phn h iu hnh 1

1.6. Cc nguyn tc xy dng h iu hnh 1

Chng II: Qun l thit b 9 8 12.1. Quan h phn cp trong t chc v qun l thit bngoi vi

2

2.2. C ch phng m 2 1

2.3. C ch SPOOL 1

2.4. Qun l File 1

2.5. Qun l file trong h iu hnh MSDOS 2

Chng III : Qun l b nh 10 9 1


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TN CHNG MCPHN PHI S TIT

TS LT BT TH KT

3.1. Cc giai on x l chng trnh 1

3.2. Qun l b nh logic- cu trc mt chng trnh 3

3.3. Qun l b nh vt l 3

3.4. Qun l b nh IBM PC ca MSDOS 2 1

Chng IV : Qun l tin trnh 13 12 1

4.1. Qun l tin trnh 7

4.2. Qun l Processor 5

Chng V : H iu hnh nhiu vi x l - h iuhnh phn tn

7 7

5.2. H iu hnh nhiu vi x l 1

5.3. H iu hnh phn tn 2

5.4. Qun l ti nguyn trong h iu hnh phn tn 4

Nhim v ca sinh vin :Tham d cc bui thuyt trnh ca gio vin, t hc, t lm bi tp do gio vin giao,tham d cc bui thc hnh, cc bi kim tranh k v cui k.

Ti liu hc tp :1. Vn Nguyn Thanh Tng, Gio trnh H iu hnh, H Bch Khoa HN

2. Milan Milenkovic, Operating systems concept and design.

3. Mc Graw Prin, Operating system.4. Prentice Hall,Modern Operating system5. H Quang Thy, Gio trnh Nguyn l cc h iu hnh, NXB KHKT H Ni, 2004.6. Hong Kim, Gio trnh Nguyn l h iu hnh, i hc Quc gia TP HCM

7. Nguyn Kim Tun, Nguyn Gia nh,Nguyn l h iu hnh, NXB KHKT H Ni,2005.

Hnh thc v tiu chun nh gi sinh vin:- nh gi da trn tnh hnh tham d bui hc trn lp, cc bui thc hnh, im

kim tra thng xuyn v im kt thc hc phn.- Hnh thc thi cui k : thi vit rc phch, thi gian lm bi: 75 pht

Thang im: Thang im ch A, B, C, D, F

im nh gi hc phn Z = 0.2X + 0.8Y.

Bi ging ny l ti liu chnh thc v thng nht ca B mn K thut my tnh, Khoa

Cng ngh Thng tin v c dng ging dy cho sinh vin.

Ngy ph duyt: 15 / 6 / 2010

Trng B mn: ThS. Ng Quc Vinh


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Chng I: NHNG KHI NIM C BN

Quan tm ca ngi dng- Cc h thng chng trnh c cu trc nh th no?- Cc h thng c c trng g?- H thng cung cp cho ngi dng nhng ti nguyn g?

1.1. Cu trc phn lp v h thng tnh tonKhi ngi dng thc hin mt chng trnh, h thng c p ng c cc yu cu hay

khngBao gm:

- H thng c chng trnh cn thc hin hay khng- C b nh lm vic hay khng- C cc thit b ngoi vi theo yu cu hay khngTuy nhin yu cu ca ngi dng l a dng, kh nng ca h thng c hn nn i khi

chi ph cho h thng kh cao song li ch m h thng mang li nh.

khc phc a ra gii php tng tnh vn nng ca h thng qua processor:

1.1.1. C s ho h lnhTrc y trong my tnh lp rp nhiu vi mch thc hin cc chc nng chuyn

dng tnh cn, sin, e_m, loga.. v vy khi s dng rt kh c th sa cha, thay i c.

Hin nay cc chc nng ny c thay th bng phn mm do my tnh vn nnghn, tc cao hn, n nh v gi thnh h.

Cc Chng trnh bao quanh phn k thut to thnh mt mi trng tnh ton. MiChng trnh mun c thc hin phi gn vi mi trng v tha hng mi trng mikh nng ca h thng. Lm cho thng tin lu chuyn d dng gia cc thnh phn ca hthng. Thng tin u ra ca mt module ny c th lm u vo cho mt module khc. Mibin i trung gian u do h thng m nhim v trong sut vi ngi s dng.

1.1.2. Tch thitb ngoi vira khi processor(micro ho procesor)- Chuyn giao mt s cng vic cho thit b ngoi vim nhim- Processor tp trung x l bit- sut cc thut ton gii quyt cc tc v trn bng cc php x l bit, byte, hon

thin phng php x l trn my tnh in t- Xy dng sn cc Modul chng trnh cung cp cho ngi dng di dng cc

chng trnh chun - th vin cc chng trnhTuy nhin trong thc t khi cc yu cu gia tng th cc chng trnh di dng th vin

ngy cng tng nn s lng, ni dung ca cc th vin tng. Gii php:

- Cung cp cho ngi dng cc cng c cho php h m t cc gii thut cn thit,

ng thi c s ho cc th vin do ngn ng thut ton v chng trnh dch rai- Ngi dng c th tc ng ln my tnh in t thng qua cc chng trnh mu

hoc chng trnh dch

1.1.3. Chuyn nguyn tc Lnh thnh MenuC ch ra lnh

- Ngi dng phi t nm bt trc cc cng vic m h thng c th lm c, qua ch th cho h thng lm vic.


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C ch Menu

- H thng gii thiu cho ngi dng cc kh nng phc v ca mnh di dng ccbng chn, ngi dng ch ch cho h thng trnh by danh mc cc cng vic vla chn cng vic c th yu cu

- Cc cng vic c phn nhm theo tng phm tr d tm kim- H thng mang tnh cht t o to: cng lm vic cng hiu su hnNguyn tc xy dng Menu

Bng li: Dng li ch chnh xc cng vic s thc hin, t chc phn gii tt D thc hin Chu hng ro ngn ng

Bng biu tng: Mi cng vic c miu t bng mt hnh nh Hp dn, d hiu vi mi loi i tng Chng c hng ro ngn ng Kh t chc v phn gii thp

Khc phc nhc im ca hai hnh thc t chc trn: t chc c hai hnh thc: Khi a hp sng hay khung tch cc ti mt biu tng th dng ch thch

xut hin Khi a hp sng hay khung tch cc p vo mt mc no bng li th

biu tng xut hinNgoi ra cn tn ti c ch phm nng, lnh chun

Tm li: H thng phi c trch nhim m bo cc iu kin vt cht v cc chngtrnh c th thc hin c ng thi phi duy tr h thng trng thi ng b (c ngha lh thng phi c chc nng qun l ti nguyn)

1.2. Ti nguyn h thngBao gm:- Khng gian: Khng gian nh

- Thi gian: Thi gian thc hin lnh- Thit b ngoi vi

1.2.1. B nh- B nh l ni lu tr thng tin.- c trng b nh

Thi gian truy nhp Phn cp Phn loi

- Thi gian truy nhp Thi gian truy nhp trc tip: thi gian trc tip truy nhp ti a ch bt

k trong b nh.

Thi gian truy nhp tun t: Khi tn ti mt cch t chc lu tr k tip.- Phn cp b nh B nh thng c phn cp theo tc truy nhp trc tip hay k tip.

B nh c gi l thc hin nu processor c th thc hin cu lnh bt kghi trong . c im ca b nh ny l thi gian truy nhp thc hin vtruy nhp tun t l bng nhau. B nh trong bao gi cng l b nh thchin.

Khng gian b nh Gi thnh


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- Phn loi b nh B nhtrong: C tc truy nhp cao nhng khng gian b nh nh B nh ngoi: C khng gian b nh ln nhng tc truy nhp thp.Thi gian truy nhp trc tip thng ln hn thi gian truy tun t. Loi b nhph bin l b nha cng, a mm, bng t, a quang.

1.2.2. Thi gian thc hin lnh- Processor l mt ti nguyn quan trng ca h thng, c truy nhp mc cu

lnh v ch c n mi lm cho cu lnh c thc hin.- Processor c dng cho nhiu tin trnh khc nhau do vic phn chia thi gian

s dng processor ca mi tin trnh phi c ti u ho, c bit l khi chng cndng chung ti nguyn khc: Chng trnh, d liu, thit b vo ra...

- Thi gian: thi gian thc hin mt cu lnh- Trong h thng c nhiu processor th thi gian ca mi processor c qun l v

phn phi ring bit nh nhng ti nguyn c lp

1.2.3. Thit b ngoi vi- S lng nhiu- Chng loi a dng- Tc x l


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cn thc hin, c b nh chy H khng quan tm n vic h iu hnh lm g nhmmc ch g, c cu trc nh th no?

1.3.2. Vi ngi qun lH iu hnh l tp cc chng trnh phc v qun l cht ch v s dng ti u cc ti

nguyn h thng

1.3.3. Vi cn b k thut

H iu hnh l h thng chng trnh trang b cho mt my tnh c th mc vt l to ra mt my logic mi vi cc ti nguyn v kh nng mi.

1.3.4. Vi cn b lp trnh h thngH iu hnh l mt h thng m hnh ho m phng cc hot ng ca my, ca ngi

dng v ca thao tc vin hot ng trong ch i thoi nhm to mi trng khai thcthun tin v qun l ti u cc ti nguyn ca h thng tnh ton

i vi cc cn b lp trnh h thng, v tr ca h l bn trong h iu hnh. H quanst cc module, cc thnh phn ca h thng, quan st mi quan h gia chng. y l quanim ca chng ta trong sut qu trnh kho st nghin cu h iu hnh.

Tm li:

H iu hnh l mt h chuyn gia ra i sm nht v hon thin nht v hai yu t: Vn m h iu hnh gii quyt ny sinh t nhng ngi lm tin hc do bi ton chnh xc v r rng.

Ngi tham gia thit k chng trnh l cc cn b lp trnh c tay ngh cao.

1.4. Phn loi h iu hnhBao gm: H iu hnh n nhim v h iu hnh a nhim H iu hnh n Chng v h iu hnh a Chng (MultiUsers) H iu hnh tp trung v h iu hnh phn tn H iu hnh phn chia thi gian v h iu hnh thi gian thc

1.4.1. H iu hnh n nhim v h iu hnh a nhimDa vo cch thc a Chng trnh vo b nh, chn Chng trnh c sn trong b

nh processor thc hin, ngi ta phn thnh: h iu hnh n nhim, a nhim.H iu hnh n nhim

- Ti mt thi im xc nh, khi mt Chng trnh c a vo b nh th nchim gi mi ti nguyn ca h thng, v v vy Chng trnh khc khng thc a vo b nh trong khi n cha kt thc.

- Nhng do cc thit b vo ra thng lm vic vi tc chm, ngi ta dng kthut SPOOLING (simultanous peripheral Operation on line): cho php to ra hiung song song cc thit b ch cho php vo ra tun t (s cp chi tit Chngsau).

H iu hnh a nhim- H iu hnh cho php ti mt thi im c nhiu Chng trnh trong b nh

trong. Chng c nhu cu c phn phi thi gian phc v CPU, b nh v thit bngoi vi. Nh vy CPU, b nh, thit b ngoi vi v.v.. l cc ti nguyn c chia scho cc Chng trnh . Vn l lm sao m bo tt nht tnh bnh ng khi giiquyt vn phn phi ti nguyn.

1.4.2. H iu hnh n Chng v h iu hnh a Chng (MultiUsers)H iu hnh n chng- Ti mt thi im xc nh h iu hnh ch cho php mt ngi s dng thao tc


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m thi.

H iu hnh a chng- H iu hnh cho php ti mt thi im c th phc v nhiu ngi s dng.

1.4.3. H iu hnh tp trung v h iu hnh phn tnH iu hnh tp trung- Trn mt h thng my tnh ch c mt HH duy nht ci my ch. Cc my trm

c khi ng nhmy ch v n ch lm chc nng nhp/xut d liu. Mi x lu tp trung my ch.

H iu hnh phn tn

- Trn mi my c 1 h iu hnh khc nhau, my ch chu trch nhim cung ng ccdch v truy nhp n cc ti nguyn chung v iu hnh ton

- h thng, cc php x l c th tin hnh my trm.

1.4.4. H iu hnh phn chia thi gian v h iu hnh thi gian thcH iu hnh phn chia thi gian (Share time)- Mt CPU lun phin phc v cc tin trnh v 1 tin trnh c th ri vo trng thi

ch i khi cha c phn phi CPU.

H iu hnh thi gian thc (Real time)- Mt tin trnh khi xm nhp vo h thng th bt k lc no u c phn

phi CPU.

1.5. Tnh cht chung ca h iu hnh

1.5.1. tin cy caoMi hot ng thng bo ca h iu hnh chun xc tuyt i

Khi chc chn ng th my mi cung cp thng tin cho ngi dng

Mi cng vic bao gi cng c kim tra, nh giV d: C:\>COPY A:\ F1.TXT B:

Kim tra lnh COPYKim tra cc iu khin

Tn ti hay khng cc a

ng c c quay khnga c truy nhp c khng

Tn ti hay khng tp tin f1.txt

Cht lng thng tin trn a nh th no?

c mt phn thng tin trong F1.TXT hay ton b

1.5.2. an ton

T chc cho d liu v chng trnh khng b xo hoc thay i ngoi mun.Chc nng bo v thng tin c chia thnh nhiu mc:

- Cc mc do h thng m nhim:V d: trong cc h thng UNIX, khi mun xohay sa i ni dung mt tp, ngi s dng phi c quyn xo sa i vi file .

- Cc mc do ngi s dng m nhim: V d: Lnh DEL *.* ca MSDOS, hthng hi li ngi s dng mt ln na trnh sai st v .


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1.5.3. Hiu quCc ti nguyn phi c khai thc trit ngay c khi iu kin ti nguyn hn ch

song vn c th gii quyt cc yu cu phc tp.Tnh ng b cao (duy tr ng trong ton b h thng)

1.5.4. Tng qutTnh k tha cc phin bn trc y

Thch nghi vi nhng thay i c th c trong tng lai1.5.5. Thun tin

- D s dng

- C nhiu mc hiu qu khc nhau tu kinh nghim v kin thc ngi dng: Giao tip dng dng lnh Giao tip dng thc n (Menu) Giao tip dng biu tng

1.6. Nguyn tc xy dng h iu hnh

1.6.1. Modul

Xy dng t cc Modul c lp quan h vi nhau thng qua d liu Vo/raTn ti c ch lin kt cc Modul c lp thnh h thng c t chc

1.6.2. Nguyn tc tng i trong nh vCc Modul c vit theo a ch tng i k t u b nh, khi thc hin chng c

nh v ti vng nh c th nh vy h thng s dng b nh linh hot hn v h iu hnhkhng ph thuc vo cu hnh b nh

1.6.3. Macroprocessor

Khi c mt cng vic c th, h thng s : Xy dng cc phiu yu cu Lit k cc bc phi thc hin Xy dng chng trnh tng ng Thc hin chng trnh

V d: Trong MSDOS ta c cc tp config.sys v autoexec.bat

1.6.4. Ph chc nngMt cng vic ca h iu hnh c th c thc hin bng nhiu phng tin khc

nhau cho php ngi dng chn gii php ti u vi bi ton ca mnhV d: Khi in tp F1.TXT c cc gii php:

C:\>COPY F1.TXT PRN

C:\>TYPE F1.TXT >PRN

C:\>PRINT F1.TXT

1.6.5. Gi tr chun (ngm nh):H thng chun b sn cc bng gi tr cho cc tham s iu khinNu trong cc cu lnh ca ngi dng cn thiu nhng tham s gi tr th h thng s

t ng ly gi tr tng ng bng gi tr chun ra thc hinV d: C:\BT> DIR

Xem a no: CTh mc no: BT

Ci g: Mi th mc con, tp trongth mc ny v khng b che


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Nh th no: y thng tin, lin tc theo d liu

Ra u: Thit b chunTham s: Mi tham s

1.6.6. Tham s- Tham s v tr: L loi tham s m ngha ca n xc nh bi v tr xut hin trong

bng tham s. ng u dng tham s

- Tham s kho: L loi tham s m ngha xc nh bng t khaV d: C:\>DIR D: /W/A/P

C:\>DIR D: /A/P/WTrong :

D: l tham s v tr/W, /A hay /P l tham s kho

1.6.7. Nguyn l bo v- Chng trnh v d liu phi c bo v nhiu mc, bng nhiu kho.

- V d trong Linux+ Mc 1: Ngi s dng phi c ti khon mi c s dng my tnh.

+ Mc 2: Ch nhng ngi s dng thuc nhm A mi c truy nhp v tpchung ca nhm A.

1.7. Thnh phn h iu hnh

1.7.1. Thnh phn ca h iu hnh- Ngn ng lm vic v giao tip: H iu hnh c quan h vi ba i tng nn tn ti

ba ngn ng lm vic v giao tip Ngn ng my (Ngn ng thc hin):

L ngn ng thc hin duy nht ca h thng. Mi ngn ng khc u phi cnh x sang ngn ng thc hin

Ngn ng vn hnh (h iu hnh):Thao tc vin giao tip vi h thng

Ngn ng thut ton:Ngi dng giao tip vi h thng: Pascal, C... (Cn phi c chng trnh dch).

- Cc Modul chng trnh ca h thng c th chia thnh hai lp: Chng trnh iu khin:

+ Qun l ti nguyn+ Qun l tin trnh+ Qun l, t chc d liu+ Chng trnh th k, iu phi nhim v

Chng trnh phc v:+ Chng trnh bin tp

+ Chng trnh dch1.7.2. Thnh phn ca MSDOS

Nhng nm 1980, khi hng Intel cho ra i b vi x l 16 bt 8086, Jim Paterson xydng h iu hnh trang b cho loi my tnh s dng b vi x l ny l 86-DOS.

Hng Microsoft mua li h iu hnh ca Jim Paterson v pht trin thnh h iuhnh PC-DOS hay MSDOS. Phin bn u tin ca MSDOS th h 1.0 ra i vo 8/1981.

- Cc ci tin c bn ca MSDOS 1.0 C thm loi Chng trnh chy EXE bn cnh cc Chng trnh COM.


14/55

- 13 -

H iu hnh tch b x l lnh thnh mt phn ni tr v mt phn ngoitr.

tin li cho vic qun l a ngi ta a ra bng File Allocation Table vittt l FAT qun l a. Mi phn t ca bng FAT tng ng vi 521 bytetrn a gi l sector, ch ra sector ny c d liu hay cn t do.

MSDOS 1.0 cho php x l l (batch) mt s lnh ca MSDOS bng cch tomt tp batch.

Ngy thng to hay cp nht tp cng c lu tr cng vi thng tin ca tp.- Cng vi thi gian, hng Microsoft nng cp h iu hnh ny ln cc phin bn

mi 2.0, 3.0, 4.0- Cc thnh phn ca MSDOS BIOS: Cha cc Chng trnh ca supervisor v qun l tp nhng cha kt ni

thnh h thng. Do cn Chng trnh kch hot. Chng trnh mi Boot Strap Loader: nm sector u tin ca a t dng

kch hot ton b Chng trnh h thng. IO.SYS: Di s h tr ca BSL bao ly BIOS, cung cp cc dch v c bn

nht nh chia s ti nguyn, qun l b nh. MSDOS.SYS: m rng IO.SYS ln na COMMAND.COM: lin lc gia ngi s dng v h thng, cha cc lnh ni

tr. Cc lnh ngoi: l thnh phn m rng theo tng lnh vc. Cc tin ch khc: Chng trnh nn a (DBLSPACE)

CU HI V BI TP1.1. Hy lit k sb v mt s c trng ca cc h iu hnh s dng.1.2. Trnh by cc c trng ca CPU, b nh, knh dn

1.3. Nhngi lng no lin quan n tc x l ca CPU

1.4. Anh, ch hy ly v d minh ha v cc tnh cht ca h iu hnh ang s dng c th1.5. Anh, ch hy trnh by v cc nguyn tc xy dng h iu hnh. Ly v d minh ha c

th.1.6. Anh, ch hy ly v d minh ha v cc thnh phn c bn ca h iu hnh ang s dngc th. Nu ngha, tc dng ca cc thnh phn .


15/55

- 14 -

Chng II: QUN L THIT B

t vn - Thit b ngoi vi tr thnh i tng lm vic ca h iu hnh khi h thng

phc tp- Cc thit b ngoi vim nhim vic truyn thng tin qua li gia cc b phn ca

h thng V vy vn t chc thng tin, phng php truy nhp ti chng nh th no

cp:- T chc thit b ngoi vi- Chin lc iu khin- Phng php pht hin v x l li

2.1. Quan h phn cp trong t chc v qun l thit b ngoi vi

2.1.1. S a dng ca ccthit b ngoi vi:- Chun: bt buc- Ph: b sung

2.1.2. Quan hgia vi x lvithit b ngoi vi- Vi x l khng th lm vic trc tip vi cc thit b ngoi vi- Vi x l cng vi thit b ngoi vi thc hin cc thao tc vo/ra Tn ti cch t chc sao cho vi x l khng ph thuc vo cc bin ng ca thit

b ngoi vi

Nguyn tc:- Vi x l ch iu khin cc thao tc vo/ra ch khng trc tip thc hin- Cc thit b ngoi vi khng trc tip gn vo vi x l m gn vi thit b qun l- Mt thit b iu khin v cc thit b ngoi vi ph thuc n to thnh mt knh

(channel)

Nh vy: thit b qun l ng vai tr nh mt my tnh chuyn dng:- Nhim v iu khin thit b ngoi vi- C ngn ng ring, lnh ring- Thit b ngoi vi v thit b iu khin hot ng c lp vi nhau v c lp vi vi

x l- Chng trnh vit trn ngn ng thit b iu khin v thit b ngoi vi gi l

chng trnh knh (channel program)

2.1.3. Thc hin cc php vo/raVi x l to ra mt chng trnh tng ng vi cng vic cn thc hin, sau chuyn

giao chng trnh knh v d liu tng ng cho thit b iu khin v tip tc thc hinchng trnh ca mnh

Processor

Driver 1

TBNV 1

Driver 2

TBNV 2


16/55

- 15 -

Cc php vo/ra c iu khin theo nguyn l Macroprocessor cho php trong lc ccphp vo/ra c thc hin thit b ngoi vi th vi x l vn hot ng song song (thc hincc tnh ton v iu khin khc khi cha cn n kt qu vo/ra)

Khi cng vic c hon thnh bo cho vi x l bit bng tn hiu ngt. Tu theo tnhiu ngt:

Vi x l ngt ngay Lu tr chx l sau

Hu b h thng c th lm vic vi cc knh vi x l phi bit ngn ng knh (ngn ng

c a vo h thng khi np hiu hnh)V d: MSDOS

Trong CONFIG.SYS

DEVICE =...

m bo tng tc cht ch gia thit b ngoi vi v vi x l th knh pht tn hiu ngtvo/ra, n lun lun bo v h thng mt tr s qua c th nh gi cht lng thc hinphp vo/ra: m trv (return code). vi x l tm dng cng vic ca mnh v chuyn sangphn tch m tr v nh gi kt qu, cht lng cng vic

2.1.4. Kt thcchng trnh knhCc lnh trong chng trnh knh kt thc khc nhau nn mt php vo/ra c th thc

nhiu mc v vy knh bo cho h thng bit kt qu php vo/ra cng sm cng tt

Cc chng trnh ng dng, chng trnh ngt vo/ra, chng trnh knh to thnh cctin trnh c lp, hot ng song song v chu s iu chung ca h thng.

2.2. C ch phng m (Buffer)c im ca thit b ngoi vi l tc chm (nh hn rt nhiu so vi tc ca vi x

l) do khi mt thit b ngoi vi lm vic h thng cn: Kch hot thit b ngoi vi Chthit b ngoi vit trng thi thch hp

m bo hiu sut s dng, h thng cn phi: Gim s lng cc php vo/ra vt l Thc hin song song cc php vo/ra v x l thng tin khc Thc hin trc cc php nhp d liu

Nh vy tn ti mt s vng nh trung gian lm ni lu tr thng tin trong cc phpvo/ra gi l phng m

C ch phng m cho php khc phc: Thc hin trc cc php nhp d liu Tch lu kt qu ra m bo x l song song gia cc php trao i vo/ra v x l Gim s ln truy nhp vt l m bo bin i topo thc hin trc hoc sau khi x l thng tin m khng

lm mt tnh lin tc ca thng tinVi vi x l th phng m chnh l cc thanh ghiV d:

a

f1.txt


17/55

Phn loi: Phng m trung gian Phng m x l Phng m vng

2.2.1. Phng m trung gian:Lu tr tm thi kt qu vo/ra nh vy tn ti hai c ch phng m:

Phng m vo- Phng m ch dng nhp thng tin. Trong h thngs c lnh a thng tinvo phng m (c vt l).

- Khi gp ch th c (READ), thng tin s c tch v chuyn t phng m vocc a ch tng ng trong Chng trnh ng dng. Nh vy, mi gi tr c lutr hai ni trong b nh (mt phng m v mt vng b nh trong Chngtrnh ng dng). Khi gi tr cui cng ca phng m vo c ly ra th phng mc gii phng (rng) v h thng a thng tin mi vo phng m trong thigian ngn nht c th.

- gim thi gian ch i, h thng c th t chc nhiu phng m vo, khi htthng tin mt phng m, h thng s chuyn sang phng m khc.

Phng m ra- Khi c ch th ghi (WRITE), thng tin c a vo phng m. Khi phng m ra

y, h thng s a thng tin ra thit b ngoi vi.- H thng cng c th t chc nhiu phng m ra.

BufferSystem

Buffer

System

Read(f,a)

aWrite(f,a)

u im:- n gin- H s song song cao (do tc gii phng vng m ln)- Vnnng, p dng cho mi php vo/ra

Nhc- Tn b nh

- Thi gian trao i- Nhiu li x l

2.2.2. Phng m x l:Thng tin c x l ngay trong phng m

Truy nhp thng tin theo a ch (tnh a ch ca thng tin trong phng m v cungcp cho chng trnh)

u im:

- Tit kim b nh- Khng mt thi gian chuyn thng tin b nh trong


18/55

Nhc:- H s song song thp- Tc gii phng phng m chm- Tnh vnnng khng cao

BufferSystem

a

2.2.3. Phng m vngKt hp c 2 loi phng m trnT chc 3 phng m

Sau mt khong thi gian ba phng m quay vng trnT chc:

- Phng m c th gn vi tng file c th: ch c xy dng khi m file hoc ngfile

- Phng m gn vi h thng: khi xy dng h thng th xy dng ngay c chphng m v ch gn vo mt file c th no

2.3. C ch SPOOL (Simultaneous Peripheral Operation On_Line - H thng m phngcc php trao i thit b ngoi vi trong ch trc tip)

Vai tr ca thit b ngoi vi: trm nhn chng trnh knh v d liu, gi cc m trngthi cho h thng phn tch

Tuy nhin: mi chng trnh v d liu ca thit b ngoi vi hot ng tng t nhthit b ngoi vi c thc v vy c th dng phn mm m phng hot ng ca thit bngoi viv coi n nh mt thit b ngoi vio.

Yu cu

ng dng:

- M phng qu trnh iu khin, qun l thit b ngoi vi- To ra cc SPOOL, m phng cc php trao i ngoi vi ngay trong lc thc hin

Chng trnh Print

Disk

Thc hin chngtrnh ca ngi dng

X lkt thc

Ra

Vo

X l


19/55

- 18 -

SPOOL: k thut x l m thit b cui trong chng trnh ca ngi dng c tmthi thay th bi thit b trung gian

- Sau khi kt thc chng trnh vo thi im thun tin thng tin s c a ra thitb cui theo yu cu ca ngi dng

- Khng can thip vo chng trnh ca ngi dng- Tin hnh ngay trong lc thc hin php trao i vo/raTc dng:

- Lm cho chng trnh ca ngi dng thc hin nhanh hn- Gim gi thnh chi ph- Khai thc thit b ngoi vi tt hn- Gim yu cu v s lng thit b- To ra k thut lp trnh tng ng

T chc SPOOL: c ch thc hin:

- Lu kt qu a ra thit b trung gian, chuyn giao kt qu ny ra phn x l ktthc

- Lu gichng trnh knh

2.4. Qun l file

L do:

- Ngi dng phi lu tr thng tin b nh ngoi v vy h iu hnh phi c vaitr sao cho ngi dng truy nhp thun tin

- Nhu cu dng chung cc file d liuH qun l file phi c cc tnh cht:- Tnh c lp ca file vi vi x l v vi thit b ngoi vi v vy h thng khi lm

vic phi qun l file theo tn- Bo v d liu: khng mt thng tin khi c s c k thut hoc chng trnh

thm ch truy nhp bt hp l- T chc c hiu qu m bo tit kim b nh ngo i v d truy nhp T chc tun t theo byte: d liu c t chc lu tr, c v ghi mt cch

tun t tng byte. Cch t chc ny c tnh vn nng, mi ng dng u c ths dng tp.

T chc tun t theo bn ghi: d liu c t chc lu tr, c v ghi mt cchtun t tng bn ghi vi kch thc c nh.

T chc cy cc bn ghi: d liu c t chc lu tr, c v ghi theo cy ccbn ghi theo trng kho.

- Mi thao tc phc tp phi trong sut vi ngi dng m bo cng c truy nhpti tay ngi dng dng n gin nht

Nh vy:- Tn ti cc cu lnh: c, ghi, to, i tn, ng, m file...- T chc thng tin trn phng tin mang tin v t ng ghi nhn s

- B trfile p ng yu cu truy nhp v tm kim Cu trc lu tr tun t, tn ti bn ghi c bit lu tr cc tham s file

Tn ti c ch th mc, b phn ho tn file phm vi nht nh, cc Thngtin lin h vi nhau bng danh sch mc ni

- C cch bo v file: Tnh: lin quan ti ton b file v c nh theo thi gian ng: xc lp khi m file c, ghi thng tin

- Xo d liu trong file: Mc vt l: ton b ni dung file


20/55

Mc logic: ngt cc mc ni lin h vi file

Phn lp:

mc ngi dng:

- Giao din tt- Mang tnh c th ca h thng

Mc h iu hnh:- Mang tnh vn nng- Tn ti nhiu thnh phn, ph thuc vo thit b v n phi lin h vi h thng

2.5. Qun l file trong h iu hnh MSDOSB nh ngoi (a t) c hai tham s chnh:- Tham s v thit b c a t- Tham s v bn thn a

2.5.1. Thit b c, ghi:Nguyn tc hot ng theo nam chm in

2.5.2. Tham s a t:Lu tr c nh trn a.

a c th c 1, 2 hay nhiu mt (side), chng c nh s th t t 0. Mi mt ctruy nhp bng mtu t (head).

Trn cc mt, thng tin c ghi theo cc ng trn ng tm (Track - rnh t) c aim u thng hng nhau. Chng c nh s th t t 0 v t ngoi vo trong tm a.

Tp hp cc rnh c bn knh bng nhau trn cc mt to thnh t tr (Cylinder)

Trn cc rnh, thng tin ghi theo tng phn mt gi l cung t (sector) c di bngnhau, mt sector c th l 128, 256, 512, 1024 byte. Cc sector c nh s bt u t 1(Hin nay nng cao dung lng lu tr trn a t, k thut LBA c s dng)

Truy nhp Vt l

Trao i Vo/ra

Thit b Vo/ra

H qun tr CSDL

P/thc truy nhp

Truy nhp Logic

HH

User


21/55

- 20 -

Sector 1 khng nm cnh sector 2 m cch mt khong no gi l h s an xen(interleave). Interleave l s nguyn t cng nhau vi s sector trn track

V d: a mm: Interleave=7

a cng h s ny t 3 n 4

a ch vt l ca 1 sector c xc nh bi: S hiu ca Side/Head

S hiu ca Track/Cylinder S hiu ca Sector

Trong thc t cn s dng khi nim lin cung (Cluster): L s cc sector lin tip nhauv mt logic v l n v phn phi b nh cho ngi dng (1 cluster c th l 2, 4, 8, 16,32... sector). a ch logic

a ch logic ca 1 sector cn c xc nh bi: S hiu ca Cluster (tnh t Cylinder 0, Head 1)

S Sector/1 Cluster

S hiu ca Sector(tnh t u Cylinder)

c/ghithng tin trn 1 sector ca aS dng ngt 13H ca BIOS c/ghi a, vi kiu d liu thanh ghi (Registers)

Gi tr cc thanh ghi:

AH: 01h: Ghi Sector; 02h: c SectorAL: S Sector cn c/ghiCH: S hiu Track/Cylinder

CL: S hiu Sector

DH: S hiu u t

DL: S hiu a (F0h = A...; 80H = HD0; 81H = HD1)ES:BX => a ch vng nh

Ch : Gi tr Sector gm 6 bit v Cylinder l 10bit:

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

Cylinder Sector

Th tc m ho Cylinder v Sector

Function CylSecEncode(Cylinder, Sector : Word) : Word;Begin

CylSecEncode := (Lo(Cylinder) shl 8) or (Hi(Cylinder) shl 6) or Sector;

End;Output:

Nu c li: Carry Flag=CY=1 v m li trong AHNu khng li: AH = 0 v ES:BX => a ch vng nh

Mt acng bao gm:- Phn h thng- Phn d liu


22/55

- 21 -

Phn h thng bao gm:

- Master boot record- Boot sector- FAT- ROOT

Hnh nh cu trc:

- MBR: Master Boot Boot chnh ca a t cng- MBR tr ti Boot Sector v nhng Boot Sector cn li (nu c)- Boot Sector tr ti Root v t Root truy nhp vo FAT1, t FAT1 truy nhp ti FileBoot sector: lun tn ti mi a tN bao gm hai phn:

- Xc nh tham s t chc ca a: c th cho mi a- Chng trnh mi phc v cho vic np h iu hnh: vng ny l bt buc vi a

h thng, vi a ghi d liu t c th b trngNp h thng: Thc cht l c Boot Sector v ghi vo vng a ch 7C00h

truy nhp thng tin trn a cn quan tm ti cc thng s:

- S byte cho mt sector- S sector trc FAT- S bng FAT- S mc vo (entry) cho root (32 byte cho mt entry)- Tng s sector trn a

- S lng sector cho mt bng FAT- S sector trn mt track- Su c, ghi

Truy nhp Boot Sector- Xc nh v tr ca n trn a- c trc tip sector thng qua ngt 13h hoc 25hV tr Boot Sector:

- a mm: sec1, u c 0, cylinder 0- a cng: sec1, u c 1, cylinder 0

MBR Boot Sector FAT2FAT1 Root File

Vng h thng

HDD FDD

Phn tham sa t

Cung t miBoot strap loader

55AA


23/55

- 22 -

A/ Bng tham sBR:

Shiu

a choffset

Chiu di(byte)

ngha

1 0 3 EBxx90 (s hiu c bit)

2 3 8 Tn h thng format a

3 B 2 S byte/sector (byte thp c lu tr trc 1234 34|12)

4 D 1 Sec/clus kch thc trong bng phn phi cho ngi dng5 E 2 K/c t u logic a t ti bng FAT1

6 10 1 S bng FAT

7 11 2 S phn t th mc gc root

8 13 2 S sec trn a nu dung lng a nh hn 32MB

9 15 1 Loi a: F8: HD; F9: FD(1.2M); F10: FD (1.44M)

10 16 2 S sec/FAT

11 18 2 S sec/track

12 1A 2 S u t

13 1C 4 /c tuyt i boot sector14 20 4 S sec trn a nu dung lng a ln hn 32MB

15 24 1 /c vt l a t: 80: C, 81: D, 00: FD

16 25 1 D tr

17 26 1 Du hiu 29h

18 27 4 Serial number

19 2B 11 Volume name

20 36 8 FAT

Cn li 482 byte cha Chng trnh mi

V d:EB BC 90 4D 53 44 4F 53 35 2E 30 00 02 20

01 00 02 00 02 00 00 F8 80 00 3D 00

12 00 BC 19 00 00 0E 00 10 00 50 00 29

D2 15 BE 18 4E 4F 20 4E 41 4D 45 20 20 20 20

46 41 54 31 36 20 20 20 F1 33

B/ Th mc gc (Root Directory)

Dy cc mc vo, mi mc vo 32 byte chia thnh:

S hiu a ch di ngha

1 0 8 Tn t/m, tp (nu thiu b sung du cch 20h)

2 8 3 Phn m rng

3 B 1 Thuc tnh4 C 10 Cha dng ti (vi MSDOS6.22)

5 16 2 Gi to lp

6 18 2 Ngy to lp

7 1A 2 Cha lin cung khi ng

8 1C 4 Kch thc tp


24/55

- 23 -

Byte s 0 trong tn th mc, tp:- Nu l 00h th phn t ny cha s dng bao gi- Nu l E5h th phn t ny c s dng nhng b xo- Nu l 2E 20h (.) phn t u tin ca th mc con. Lin cung khi ng (Starting

cluster) ca phn t 1 ch chnh n

- Nu l 2E 2Eh (..) phn t th hai ca th mc con. Lin cung khi ng (Startingcluster) ca phn t 2 ch th mc m- Lin cung khi ng (Starting cluster) ca th mc gc vi s hiu: 00h

Byte thuc tnh:A D V S H R

Trng s: 32 16 8 4 2 1A: thuc tnh lu tr

D: th mc

V: Nhn aS: h thng: cc chng trnh c c quyn h thng mi c th truy nhp

H: n nh du mt tp b che R: ch c

V d:

Tp IO.SYS vi cc thuc tnh: A S H RTrng s : 32 4 2 1 Gi tr: (39)10:27h

Tp COMMAND.COM vi cc thuc tnh: A

Trng s : 32 Gi tr: (32)10:20h

Th mc TP : DTrng s : 16 Gi tr: (16)10: 10h

Kim tra thuc tnh mt tp:

c gi tr trong byte Attribute (At)Thc hin php AND tng ng vi trng s ca cc thuc tnh

V d:Thuc tnh H: At AND 20

Th mc con: At AND 160Gn thuc tnh mt tp:

Thc hin php OR tng ng vi trng s ca cc thuc tnh

V d:


25/55

- 24 -

Thuc tnh H: At OR 2

Xo thuc tnh mt tp:Thc hin php AND tng ng m b1 tng ng vi thuc tnh

V d:Thuc tnh R(thc hin php AND vi 1111 1110): At AND FEh

Thuc tnh H (thc hin php AND vi 1111 1101): At AND FDh

Ngy, gi to lp h thng:Byte Time: xxxxx xxxxxx xxxxx

gi pht giyByte Date: xxxxxxx xxxx xxxxx

s nm thng ngy (Gi tr nm tnh t nm 1980)

C/ Bng FATChc nng:

- To danh sch mc ni cc Cluster ca cng mt tp (qun l b nh s dng)- Qun l b nh t do (vng b nh cha dnh cho tp tin hay th mc no)- nh du cc Bad Cluster (nng cao tin cy a)

Bao gm:- Dy cc phn t, mi phn t c th l: 12,16, 32bit tng ng cho FAT12, FAT16,

FAT32.- Cc phn t c nh s 0,1,2..- T phn t th 2, mi phn t trong FAT tng ng vi mt Cluster v ngc li

FAT12: Dung lng: 212= 4096KB = 4MBFAT16: Dung lng: 216= 64MB vi 2Sector/1Cluster

216= 128MB vi 4Sector/1Cluster

216= 1024MB vi 32Sector/1Cluster

FAT32: Dung lng: 232= 8GB vi 2Sector/1Cluster

- Phn t th nht: tt c cc bit l 1 do Vi a cng: HD: s hiu FF8hVi a mm: FD: s hiu FF0h

- Du hiu kt thc 1 chui Cluster l FFFh hoc FFFFh

V d:a mm 1.44MB vi FAT12

Starting Cluster: 6:

tng tc truy nhp, ngay ln truy nhp u tin lm vic vi a t, h thng s

FF0

FFF

8

5

FFF

9

4

7

3


26/55

- 25 -

c lun FAT v ROOT vo RAM, nh vy h thng ch cn truy nhp v o b nh ly thng tin, khng cn phi truy nhp li a t do vy tngc tc v gim cdi chuyn c kh ca u t.

c FATuses crt,MSDOS;

const S16:string[16]='0123456789abcdef';

var B:array[0..511]of byte;

i,j:integer;start:word;

drv,cyl,head,sec,numsec,drive:byte;

Function R_sector (drive,cyl,head,sec,numsec:byte):integer;

var reg:registers;

begin

with reg do

begin

dl:=drive;dh:=head;ch:=cyl;

cl:=sec;al:=numsec;ah:=2;

es:=seg (b);bx:=ofs (b);

end;

intr ($13,reg);

end;

Function R_fat (var start:word):word;

var k,k1,k2,k3,tg,l:integer;ch:char;

beginfor i:=0 to 511 do b[i]:=0;

if (drv=0)or (drv=1)then

begin

drive:=0;head:=0;

end else

begin

drive:=$80;head:=1;

end;

i:=start;

if (drv=0)or (drv=1)then

begin

j:= (i*3)div 2;k:=j div 512;

tg:=R_sector (drive,0,head,2+k,1);

j:=j mod 512;

l:=memw[seg (b[j]):ofs (b[j])];

if odd (i) then l:=l shr 4

else l:=l and $0fff;

end

else

begin

j:=i*2;k:=j div 512;

tg:=R_sector (drive,0,head,2+k,1);

j:=j mod 512;

l:=memw[seg (b[j]):ofs (b[j])];

l:=l and $0fff;

end;

k1:=l shr 8+1;k2:= (l shr 4)and $0f+1;k3:=l and $0f+1;

write (s16[k1],s16[k2],s16[k3],' ');

if (s16[k1]+s16[k2]+s16[k3]'fff')then R_fat:=l elsebegin

writeln;writeln ('End of file press any case:');

ch:=readkey;

if (ch='q')then halt (1);

end

end;

Begin clrscr;

write ('Ten odia:');readln (drv);

for start:=7 to 150 do i:=r_fat (start);

End.


27/55

- 26 -

D/ Partition

Bao gm: 4 phn t, mi phn t 16byte chia thnh 4 trng, mi trng 4byte.Mi phn t khc khng xc nh 1 phn t c s dng nh 1 a t c lp

Nu bit a ch vt l u c th tnh c a ch logic u, cc tham s cn li

a ch vt l u: 4byte

SYS: byte h thngBng 00h nu a l a lm vic

Bng 80h nu l a h thng (phn cha h thng ct tn l a C)

H: cha s u cS: cha s sectorCYL: s cylinder

a ch vt l cui: 4byte

TYPE:00h: cm c ghi (khng cho php truy nhp)

01h: p dng cho a c dung lng nh hn 4MB (FAT 12)04h: p dng cho a c dung lng nh hn 32MB (FAT 16)06h: p dng cho a c dung lng lnhn 32MB (FAT 16)

0Ch: p dng cho a c dung lng ln hn FAT32

SYS:

Bng 80h nu l a h thng TYPE = 51 (DM: disk manager)Bng 05h: loi m rng (extended) cu trc logic nh mt a cng vt l

v vy tn ti master boot ring, c partition ring.

V d:Vi FAT16: a ch bt u ca Partition l 1BEh

80 01 01 00 06 3F FF 4D 3F 00 00 00 41 00 34 00

00 00 00 00...00 00

00 00

55 AA

/c V/l u T ng s Sector/c V/l cu i /c Logic cu i

SYS H CYSS

TYPE H SYSS


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c MBRuses crt,MSDOS;

const s16:string[16]='0123456789abcdef';

var reg:registers;

B:array[0..511]of byte;

i:integer; j,k:byte;ch:char;

begin clrscr;

with reg do

begin

dl:=$80;dh:=0;

cl:=1;ch:=0;

al:=1;ah:=2;

bx:=ofs (b);es:=seg (b);

end;

intr ($13,reg);

for i:=$1be to 511 do

begin

j:=b[i]shr 4+1;

k:=b[i]and$0f+1;

write (s16[j]:2,s16[k]);

if (i+1)mod 16 =0 then

begin

write (' ':5);

for j:=i-15 to i doif (b[j]


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Chng III: QUN L B NH

3.1. t vn B nh l 1 ti nguyn khng th thiu c, ng vai tr lu tr thng tin x l v

vy n c lin quan ti tc x l.Mt phn b nh trong dng lu tr nhn (kernel) ca h thng- tp cc chng trnh

iu khin thng xuyn c mt b nh trong thc hin khi cn.

Chc nng khc ca h iu hnh l bo v chng trnh v d liu khi b h hng,truy nhp mt cch khng hp thc khi cc chng trnh khc hot ng.

Cc bc x l chng trnh:

Chng trnh ngun: Ccchng trnh c vit di dng ngn ng thut ton quachng trnh dch dch sang ngn ng my.

Cc php nh x: h thng phi chuyn i cc tn ngoi thnh tn trongTn ngoi: do ngi dng tTn trong: tn do h thng t trong qu trnh dch, dng phn phi b nh v xc lp

mi quan h n tr tn a ch (do hm a ch thc hin)Hm a ch xc lp quan h gia khng gian tn v khng gian b nh(b nh logic)

Modul dch ca chng trnh l chng trnh vit trn ngn ng my, nhng n mic xt c lp khng nhng vo quan h chung ca ton h thng v vy cn phi chuynthnh chng trnh thc hin.

Vic tp hp cc chng trnh modul dch thnh cc chng trnh dng thc hin dochng trnh bin tp (LINK) m nhim.

nh v chng trnh: np chng trnh vo b nh trong c th, t vo v tr xc nhv sa a ch cho thch hp vi mi trng khai thc c th.

Vi chng trnh .COM: dung lng nh hn 64KB nn c th t mt ni no vthc hin ngay khng cn sa i

Vi chng trnh .EXE: chng trnh c chun b gn dng thc hin nhng cha lprp v vy khi a vo b nh phi lp rp theo chng trnh iu khin (bin tp li)

Ch lp trnh: VLG: dung lng b nh logic

VPH: dung lng b nh vt l

Ch b nhthc:

Yu cu VLG< VPHnh vy b nh s dng nh hn b nh ta c Ch b nh o:Khng c rng buc gia VLG v VPHnh vy khi qun l khng gian b nh:

Logic: quan tm ti chng trnh c b tr nh th no\ Vt l: quan tm ti chng trnh v d liu

Tm li: quan tm ti vic xc lp quan h gia hai b nh

Q/l T/trnh

C.trnhngun

Tnngoi Tn trong

Modulthc hin

Moduldch

C.trnhthc hin

THCHIN

Qun l b nhChng trnh dch


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3.2. Qun l b nh logic - cu trc mt chng trnhMt chng trnh c th bao gm nhiu modul, cc modul c th c cng mt dng cu

trc hoc c nhng cu trc khc nhauChng trnh c th c cc dng cu trc:

- Tuyn tnh- ng- Overlay- Phn on- Phn trang

3.2.1. Cu trc tuyn tnhSau khi bin tp cc modul c tp hp thnh 1 chng trnh hon thin cha y

thng tin c th thc hinThc hin: nh v 1 ln vo b nh

u im:- n gin, ch vic tm cc mc ni- Khng c s g b v thi gian- Tnh lu ng cao: c th chuyn t ni ny ti ni khc

Nhc:- Lng ph b nh v phi s dng vng b nh ln hn mc cn thit

3.2.2. Cu trc ngTng modul c bin tp ring bitKhi thc hin ch vic np modul u tin vo b nhKhi cn modul khc ngi s dng phi s dng lnh macro h thng np nh v

modul hoc xo modul ra khi b nhV d: Lnh Macro

Attach: np, gn vo

Load: np modul vo nhng cha thc hin

Delete: xo modul khi b nh

Ngi dng c th tham gia trc tip vo qu trnh nh v

u im:- Tit kim b nh

Nhc:

- Yu cu ngi dng phi bit kch thc h thng- Thi gian thc hin ln, va thc hin va nh v- Km linh ng

3.2.3. Cu trc Overlay

Cc modul chng trnh c chia thnh tng lp- Lp 0: modul gc- modul u tin c gi- Lp 1: modul c modul lp 0 gi (khng cn c gi ng thi)- Lp 2: modul c modul lp 1 gi- B nh dnh cho chng trnh c chia thnh cc phn, mc b nh v mc chng

trnh

bit modul no thuc mc no ngi dng phi cung cp thng tin cho bit:- S mc, modul tng ng vi mc (gi l s overlay hay file Overlay - OVL)


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- Modul mc 0 c 1 file chng trnh ring, khi cn np modul no th hthng tm kim trong overlay v np vo b nh mc overlay tng ng

- Duy tr hot ng chng trnh theo s overlay gi l supervisor overlay

Khi np vo mc dng ri th modul c b xoV d:

u im:- Tit kim b nhngi dng khng phi can thip vo chng trnh ngun- Cc modul khng phi lu tr nhiu ln

Nhc:

- Ngi dng phi cung cp s overlay- Hiu qu s dng b nh tng dn ti 1 mc no th dng li- Hn ch 1 s cch gi chng trnh con

3.2.4. Cu trc phn onKhi chng trnh ca ngi dng c bin tp to thnh cc modul ring bit, tp hp

cc chng trnh l 1 bng iu khin cho bit chng trnh c th s dng nhng modul nothng qua SCB (segment control block)SCB cha 1 s thng tin tr gip nh v chng trnh, da vo SCB np modul vo

trong b nh.

Khi thc hin chng trnh da vo SCB kim tra xem modul c trong b nh haykhng, nu cha c trong b nh th chng trnh c np vo bt k vng nh no .

u im:

- Cc modul khng cn phi naptucj v khng cn c v tr c nh- Ngi dng khng cn phi khai bo bt k thng tin ph no- Thc hin nhanh hn so vi s overlay- Hiu qu tng dn theo kch thc b nh

Nhc:- Ph thuc cu trc ban u ca chng trnh ngun

3.2.5. Cu trc phn trangChng trnh ca ngi dng c chia thnh tng trang c kch thc ging nhau

c qun l bi bng qun l trang

Khi thc hin s np dn tng trang theo nhu cu v vy hn ch lng ph b nh

C s h tr ca phn cngy h s tch tr b nh ln cao


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Phn cp b nh:

Phn Trang:

ROM (384B):

Ghi c 1 ln Khng cn ngun gi Tc truy nhp cao

S cp: 640KB u tinExpended:

Phc v cho Vo/ra Processor cn lm vic trc tip vi b nh ny Extended: i hi ch m rng

Ngoi:

Disk: khi lng ln, thi gian lu tr lu diChuyn dng: CMOS (64KB): lu tr thng tin cu hnh R: truy nhp nhanh, phi phi hp vi CPU Buffer: hot ng nh 1 my tnh chuyn dng

Cache: phc v Vo/ra

3.3. Qun l b nh vt lB nh c lch thc c th v vy nhy cm vi cc kiu s dng c th

3.3.1.Phn chng c nhB nh c chia thnh n phn khng nht thit phi bng nhau, mi phn s dng nh

1 b nh c lp gi l ChngBao nhiu Chng th c by nhiu chng trnhMi chng trnh c 1 danh sch qun l b nh t do cha s dng ring

Chng trnh c np vo chng no s tn ti cho ti khi kt thcu im:- n gin- D bo v- Tn ti cng c bn trong b nh c th phn chia li h thng- C th phn loi cc chng trnh trc khi thc hin v vy c th t chc phc v

gn ti uNhc:- B nh b phn on nn khi phn chia li s thay i ng bin v vy thng tin b

xo

3.3.2. Ch phn chng ngCh tn ti 1 danh sch qun l b nh t do cho ton b h thng nh.Mi chng trnh khi xut hin c phn phi 1 vng nh ring lin tc c s dng

nh 1 b nh c lp

u im:

- H s song song cao, khng c nh- S chng trnh thc hin c th thay i- Khng b phn on nn c th thc hin 1 chng trnh bt k min l c b

nh


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- C ch i ch( b nh th lm vic)- H thng iu khin khng b sao chp i ni khc

Nhc:

- Hiu qu s dng b nh khng cao - Nu c s c k thut th chng trnh s b ph hu- S phc tp- Xut hin hin tng phn on ngoi

Khc phc:

- B tr li b nh tm thi im thch hp ln lt dng cc chng trnh ang cthc hin

- a 1 s chng trnh t vng nh trang sang nh ngoi

3.3.3. Ch phn onChng trnh c cu trc phn on. (c bin tp thnh cc modul ring bit Tn

to bng SCB)

Ngi dng hon ton khng quan tm ti SCB v chng trnh ca h c b tr nhth no trong b nh

SCB bao gm cc phn t, mi phn t tng ng vi 1 modul c lp.

Mi phn t bao gm 3 trng:

Trng D:

0: cha np vo b nh

1: np

Trng A: a ch ni np modul vo b nh

Trng L: di modulBan u D v L c gi tr, L ch kch thc modul v D=0 (cha np), SCB c xy

dng ngay khi bin tp

Khi thc hin SCB c np vo trong b nh, a ch ca n c a vo thanh ghiqun l on RS (register segment)

a ch truy nhp d liu c biu din di dng cp (s,d)

s: s hiu segment (modul) cn truy nhp

d: a ch tng i tnh t segmentTruy nhp: 2 ln hng ti b nh

- Ln 1: Ly ni dung ca thanh ghi (RS) ghp vi s truy nhp ti phn t th strong bng SCB

- Ln 2: da vo (khi D=1) ly a+d truy nhp ti d liuu im:

- p dng trn my bt k- Cho php s dng chung cc modul trong b nh

Nhc:- Hiu qu ph thuc cu trc ban u ca chng trnh ngun- Phn on ngoi: b tr li b nh

Nu xut hin nhu cu b tr li:

- a ra modul tn ti duy nht trong b nh- a ra modul c ln s dng cch ay lu nht- a ra modul c tn sut s dng thp nht

D A L


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3.3.4. Ch phn trang(nh x b nh logic thnh vt l)B nh vt l c chia thnh tng phn bng nhau gi l Trang, cc trang c nh

s th t 0,1,2..Chng trnh phi c cu trc trang

Trang trong chng trnh phi c cng kch thc trang vt l

1 trang vt l: 256byte-4KB

Khi lm vic chng trnh c bin tp theo tng trang to ra cc PCBPCB: l tp hp cc phn t mi phn t ng vi 1 trang ca chng trnh

Bao gm 2 trng:

Trng D: du hiu cho bit trang c np vo b nh hay cha0: cha

1: np

Trng AP: a ch trangKhi thc hin :

PCB c np vo b nha ch u c a vo thanh ghi RP

a ch d liu c biu din di dng: (p,d)p: s hiu trang

d: offset tnh t u trang

Truy nhp d liu: 2 hng ti b nh- Ln 1: ly RP+p truy nhp ti trang p trong PCB

- Ln 2: i d=1 ly Ap ghp vi d truy nhp d liu

u:- Khng c hin tng phn on ngoi- Hn ch vic thiu b nh- Khi thiu b nh c th gii phng bng cch a 1 trang ra ngoi

o Trang tn ti lu nht trong b nho Trang c s ln s dng cch ay lu nht o Trang c tn sut s dng thp nht

Nhc:

- Bng PCB c th c kch thc ln

3.3.5. Ch kt hp phn trang v phn onB nh c t chc theo kiu phn trang

Chng trnh c t chc theo kiu phn on (Tn ti SCB)Mi modul c bin tp theo ch phn trang v vy mi modul c 1 PSB ring

Mi phn t ca SCB s qun l cc PCB tng ng ca modul

D: xc nh PCB vo b nh hay chaA: a ch u PCB

L: di ModulKhi thc hin mt chng trnh SCB c np vo trong b nh. a ch u ca n

c a vo thanh ghi RsB nh c chia thnh 3 phn:

D AP


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Phn1: cha SCB

Phn2: cha cc PCBPhn3: cha cc trang chng trnh v d liu

Truy nhp:a ch biu din: (s,p,d)

Trong :

s: modul cn truy nhpp: trang cn truy nhp

d: a ch offset tnh t u trangTruy xut nh: Mi ln truy nhp cn 3 ln hng ti b nh

- Ln1: ly ni dung RS+s: truy nhp phn t s ca SCB- Ln2: d=1: ly A+p truy nhp phn t th p ca PCB th s

- Ln3: Dp=1: ly AP ghp vi d truy nhp d liu

u:- Kt hp u ca phn on v phn trang

- Chng hin tng phn on ngoi- m bo s dng hiu qu b nh

3.4. Qun l b nh IBM PC ca MSDOSH thng MSDOS c chia thnh 4 mc 0,1,2,3

- Mc 0: Nhn h iu hnh (Kennel)- Mc 1: Qun l thit b, File

- Mc 2: Chng trnh phc v h thng- Mc 3: Chng trnh ng dng

Mc u tin 0-3

Mt chng trnh ch c quyn truy nhp ti chng trnh v d liu cng mc utin hoc km mc u tin hnB nh phn phi cho 1 chng trnh chia lm 2 loi:

B nh chung:

- Vng nhm mi chng trnh u c bit v c quyn truy nhp- C bng tham siu khin GDT (Global Descreption Table)B nh ring:

- Phn phi cho chng trnh no th ch c chng trnh c bit v c quyntruy nhp

2


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- C bng tham s LDT (Local Descreption Table)

Vi my PC c 2 ch lm vic l:- Ch thc (Real mode)- Ch bo v (protect mode)Nguyn tc:

B nh c chia thnh tng khi

Real mode:o Dung lng khi


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Chng IV: QUN L TIN TRNH

4.1. Qun l tin trnh

4.1.1. Khi nimPhng php tip cn:

Coi tin trnh l nhm cc byte c ni dung thay i theo 1 lut no , lut hng dn

Processor thc hin. Saltzer: Tin trnh l chng trnh do 1 processor logic thc hin

Dijkstra: Tin trnh l nhng g lin quan n h thng tnh ton xut hin khithc hin 1 chng trnh

nh ngha ca Horning & Randell: Tin trnh nh 1 qu trnh chuyn t trngthi ny sang trng thi khc di tc ng ca hm hnh ng v xut pht ttrng thi ban u no

Hm hnh ng : nh x trng thi sang hnh ng, hnh ng da votrng thi ban u

T chui cc trng thi n cng vic

s0 s1 s2 s3 s4 s5 s6 s7 sn-1 sn sn+1

Quan im ca ngi dng: Tin trnh l mt qu trnh thc hin chng trnh

4.1.2. T chc tin trnhT chc

Tin trnh tng ng cu trc thng tin cho php xc nh n tr tin trnh (cu trcthng tin ny gi l khi m t thng tin bao gm):

- Bin trng thi thng tin : Trng thi hin ti ca tin trnh

- Vng b nh lu tr gi tr ca cc thanh ghi tin trnh s dng

- Thng tin v ti nguyn tin trnh ang s dng hoc c quyn s dng.Hnh thnh tin trnh

- Khung chng trnh gn cho cc gi tr v ti nguyn c th

- Thng tin c xy dng khi c yu cu v hu b khi cng vic hon thnh

Phn loi tin trnh- TT tun t : mt tin trnh ch btu sau khi tin trnh kia kt thc

- TT song song: Thi im bt u ca tin trnh ny nm gia thi im bt u vkt thc ca mt tin trnh khc.

Quan h:c lp: 2 tin trnh khng c quan h trc tip g vi nhau

Yu cu : bo v thng tin sao cho mt tin trnh khng lm hng d liu vchng trnh ca tin trnh khc, nh vy phi phn phi ti nguyn hp l

Tin trnh trao i thng tin vi nhau: mt tin trnh c th gi thng bo cho tin trnhkhc, t chc cc vng nh lm hm th.

Phn lp: Trong qu trnh hot ng ca mt tin trnh c th khi to mt tin trnhkhc hot ng song song: (chng trnh chnh, chng trnh con)

C ch cp pht ti nguyn:

- Phn tn: Phn phi ti nguyn cho c chng trnh chnh v chng trnh con

- Tp chung: Ti nguyn chc phn phi cho tin trnh chnh


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Tin trnh ng mc: Nhng tin trnh c mt s ti nguyn s dng chung theo nguyntc ln lt.

4.3.3. iu tin trnh - Ti nguyn GngTi nguyn Gng: Ti nguyn phn phi cho mt ngi phc v, nh vy ti mt thi

im nu ng thi c nhiu tin trnh mun s dng ti nguyn Gng: iu tin trnh khng c khi no c mt tin trnh chim dng ti nguyn

on chng trnh c s dng ti nguyn Gng gi l on GngV d:

TTA ghi ni dung bin Dem vo TgA (bin cc b)

TTB ghi ni dung bin Dem vo TgBTTA tng TgATTB tng TgB

Nu khng k, c th hiu lm l bin Dem tng 2 n v. Song thc cht c 2 tintrnh A v B u tng ni dung Dem, song ni dung ny ch tng 1n v. Cn phi c cchgii quyt c th.

- Dem : Ti nguyn Gng- on chng trnh x l bin Dem : Chng trnh gng : on gng.Khc phc ng :

- Ti mt thi im c khng qu mt tin trnh nm trong on Gng- Khng mt tin trnh no c php lu v hn trong on Gng- Khng mt tin trnh no phi ch v hn ngoi on GngCng c iu tin trnh qua on gng :

- Cp thp: nm ngoi tin trnh c iu - Cp cao: nm trong tin trnhCng c iu cp thp :- Phng php kho trong- Phng php kim tra v xc lp

- K thut n boa,Phng php kho trong(Kim tra lun phin)Nguyn tc: hai hay nhiu tin trnh cng nh ghi vo mt a ch no ca b nh

trong th s k thut ch cho php mt tin trnh lm vic cn tin trnh khc phi chMi tin trnh: s dng mt byte trong vng b nh chung lm kho, khi vo c on

Gng, gn gi tr l 1, thng bo cho cc tin trnh khc bit c tin trnh s dng tinguyn gng

Gii thut DelkerBegin

k1 := 0; k2:= 0; tg:=1;

kt1:=1; kt2:=1;

beginrepeat

k1:=1;

While k2=1 do Ct2

if Tg=2 then begin

k1:=0;

While tg=2 do Ct2

k1:=1;

end;

k1:=0; tg:=2;

until kt1=0;

repeat


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k2:=1;

While k1=1 do Ct2

if Tg=2 then begin

k2:=0;

While tg=1 do Ct2

k2:=1;

end;

k2:=0; tg:=1;

until kt2=0;

uim- D t chc thc hin- C tnh cht vn nng p dng cho mi cng c v mi h thng.

Nhc:

- phc tp t l vi s lng tin trnh v s ti nguyn gng

- Mt tin trnh c th b ngn chn bi tin trnh th 3- Khi tc hai tin trnh kh chnh lch, mt trong hai tin trnh phi chb.Phng php kim tra v xc lp (Phng php Perterson)Tng ng vi phng php kho trong s dng cc gi tr kim tra l cc bin trng

thi: tham s (cc b, ton cc).

Gii thutPAR l mt lnh gm hai tham s: L: cc b (Local) G: ton cc (Global)

Chc nng PAR

Gn L = G v gn G = 1; Hai lnh trn phi c thc hin lin tc khng b chia r.

Mi tin trnh s s dng hai bin l bin local ca mnh v bin global caton Chng trnh.

Gii thutVar L1, L2, G: byte;Begin

G:=0;

begin

TT:=1;

repeat

L1:=1;

while L1=1 do PAR(L1);

{on gia tin trnh 1}G:=0;

{phn cn li ca tin trnh 1}until false

TT:=2;

repeat

L2:=1;while L2=1 do PAR(L2);

{on gia tin trnh 2}G:=0;


end;

End;

u im:

- Khc phc c phc tp ca thut ton, phc tp thut ton khng ph thucvo s lng tin trnh.


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Nhc im:

- Vn cn hin tng ch i tch cc.

c.KT n bo (Semaphore - Dijkstra)H thng s dng bin n bo nguyn c bit (Semaphore) s. Ban u s nhn mt gi

tr bng kh nng phc v ca ti nguyn gng. H thng c hai php thao tc trn s l P(s)v V(s).

P (s): Proberen (ting H Lan) c ngha l gimGim S i 1 n v

Nu s 0 tip tc thc hin tin trnhNgc li a tin trnh vo dng xp hng

V (s): Verhogen c ngha l kim tra

Tng S ln 1

Nu s 0 kch hot mt tin trnh ra hot ng

Gii thut:Var s: byte;

Begin

s:=1;

begintt:=1;

repeat

P(s)

{on gia tin trnh 1}V(s);


tt:=2;

repeat

P(s)

{on gia tin trnh 2}V(s);


end;

End;

- c im quan trng l 2 php P v V l lin tc, trong qu trnh thc hin P hoc Vth processor khng b ngt chuyn sang cng vic khc.

- Tuy nhin cc php x l ny c th khng tn ti trn cc my v P v V phi lmvic vi dng xp hng v thng tin lu tr kh ln. khc phc iu ny ngi ta xydng cc th tc procedure thc hin cc php x l ny.

+ u ca thn th tc bao gi cng ra lnh cm ngt tc l chn mi tn hiu voprocessor CLI, tr nhng tn hiu bt buc (ngt khng chec).

+ Cui thn th tc c lnh gii phng ngt (STI).

d. Cng c iu cp caochng trnh th k(Monitor)

c im:

- Nm ngoi tin trnh ca ngi s dng- Ngi s dng khng bit ti nguyn g v khi no thuc on gng

Chng trnh th k (Monitor): cu trc c bit bao gm cc th tc, cc bin v cutrc d liu hot ng trong ch phn chia th gian , h tr vic thc hin tin trnh, vicc thuc tnh:


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- Cc bin v cu trc d liu trong Monitor ch c th c thao tc bi cc th tcnh ngha bn trong Monitor

- Ti mt thi im, mt tin trnh duy nht c lm vic vi chng trnh th k

- Mi ln s dng ti nguyn mi, h thng gn chng trnh th k vi tin trnh

Trong mt Monitor c th nh ngha cc bin iu kin C v hai thao tc l Wait () vSignal ():

- Wait (C): chuyn trng thi tin trnh sang trng thi kho v t tin trnh vo hngi trn bin iu kin C- Signal (C): nu c mt tin trnh ang b kho trong hng i ca C th ti kch hot

tin trnh v tin trnh s i khi Monitor

Thut tonWait (C)

begin

status (p)=kho

enter (p, f (C)) { a p vo hng i}end;

Signal (C)

begin

if f (C)nil then

exit (q, f (C)) { a q ra khi hng i}end;

4.1.4. Tnh trngtc nghnTc nghn: Khi c nhiu ti nguyn gng trong mt tin trnh, cc tin trnh sri vo

tnh trng ch i ln nhau

Tnh trng tc nghn: hai hay nhiu tin trnh cng ch i mt s kin v nu khng ctc ng c bit t ngoi th s ch i y l v hn

- Phng chng:

- Phng nga : trnh khng tin trnh ri vo tnh trng tc nghn

- D bo v trnh : Kim tra xem tin trnh c ri vo tnh trng tc nghn hay khng,thng bo kp thi trc khi tc nghn sy ra

- Nhn bit v khc phc : Pht hin cc tin trnh b tc nghn v gii quyt

a. Phng nga

Xem xt cc iu kin tc nghn:- Thiuti nguyn Gng- Chv hn khi cha c vo on Gng

- Khng c h thng phn phi li ti nguyn

- Tn ti ch i vng

iu kin 1: Dng k thut SPOOL: Khi kt thc tin trnh th kt qu c chuynngc li ti nguyn vt l m sever yu cu, vic chuyn ngc ny theo nguyn tc ln ltv do chng trnh h thng m nhn nh vy khng xy ra xung t

iu kin 2: Phn phi trc ti nguyn, tin trnh ch c bt u khi nhn tinguyn trong mt s ln phn phi

iu kin 3: To cc im gc: H thng s lu li ton b thng tin trng thi tintrnh, nu cn thit c th hu tin trnh, gii phng ti nguyn, sau nu cho php s tiptc cng vic bng cch khi phc trng thi cui.

iu kin 4: Chi vng: Phn lp ti nguyn, tin trnh ch nhn c ti nguynmc cao hn sau khi tr li ti nguyn mc thp.


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b. D bo v phng trnh

Khng phng nga nhng mi ln phn phi ti nguyn th kim tra xem vic phn phi c kh nng y h thng vo tnh trng tc nghn khng? Nu xut hin nguy c trn thtm cch gii quyt c th trc khi tc nghn c th xy ra

Thut ton:

- C n tin trnh- H thng c k thit b- Tin trnh i yu cu ti a mt lc max (i) n v thit b c th thc hin, nhng

hin ch nhn c f(i) n v thit b- Tin trnh i kt thc kt (i)=true

Thut ton :t:=k;

for i:=1 to n do

begin

t:=t-f (i);

cl[i]:=max[i];

kt[i]:=false;

end;

Flag:=True;

While Flag do

beginflag:=false

For i:=1 to n do

if not kt[i] and (cl[i]


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Cc ti nguyn: R1, R2, R3

Tng cc ti nguyn ca h thng k = 9R1 + 3R2 + 6R3

Trng thi hin thi cc tin trnh:

Tin trnh Max (i) f (i) t

R1 R2 R3 R1 R2 R3 R1 R2 R3

P1 3 2 2 1 0 0 4 1 2P2 6 1 3 2 1 1

P3 3 1 4 2 1 1

P4 4 2 2 0 0 2

Gi s P2 c yu cu 4R1 v 1R3, khi vic tho mn P2 c y h thng ti tnhtrng tc nghn hay khng?

4.1.5. Ngt(Interupt)Phng tin cc thit b trong h thng bo cho Processor bit vic thay i trng

thi ca mnh - cng c chuyn iu khin ti mt tin trnh khc

- Ngt l hin tng tm ngng thc hin mt tin trnh chuyn sang thc hin mttin trnh khc khi c mt s kin xy ra trong h thng tnh ton.

Ct gi cc thanh ghi

Khi phc cc thanh ghi

Chng trnh chnh Chng trnh con

- C th hiu tm ngha thc hin mt tin trnh l thc hin mt Chng trnh, tintrnh b ngt c th coi l Chng trnh chnh, cn tin trnh x l ngt c th coi l Chngtrnh con.

- Chng trnh con x l ngt l mt Chng trnh ngn ng my hon ton bnhthng. Chng trnh ny a ch kt thc bng lnh IRET (Interupt RETurn), n ra lnh chob x l quay v thc hin tip Chng trnh chnh ng t ch m n b ngt.

- i vi cc h thng tnh ton vic gi ngt dng cho vic cc b phn khc nhau cah thng tnh ton bo cho processor bit v kt qu thc hin cng vic ca mnh.

Phn loi ngt:- Ngt trong: ngt do cc tn hiu ca procesor bo cho processor- Ngt ngoi: ngt do cc tnh hiu bn ngoi bo cho processor- Ngt cng: ngt c gi bi cc Chng trnh c cng ho trong cc mch in

t.o Ngt che c: (Maskable Interupt):

L ngt c th dng mt n ngn cho khng ngt hot ng. Ta c th tcc bt trong mt l bng lnh CLI (CLear Interupt flag).V d: Ngt chut l ngt cng c th b che

o Ngt khng che c (Non Maskable Interupt):


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L ngt khng th dng mt n che c (c u tin cao nht)V d: Ngt 2 bo hiu c li trong b nh.

- Ngt mm: ngt c gi bng mt lnh trong Chng trnh. Lnh gi ngt tChng trnh ngn ng my l lnh INT (INTerupt), cc lnh gi ngt t Chngtrnh ngn ng bc cao s c dch thnh lnh INT.

- Cc ngt khcX l ngt

Lu c trng s kin gy ngt vo ni quy nh Lu trng thi ca tin trnh b ngt vo ni quy nh Chuyn iu khin ti Chng trnh x l ngt Thc hin Chng trnh x l ngt, tc l x l s kin Khi phc tin trnh b ngt

Vc t ngt:- Khi ngt c to ra, ni pht sinh n khng cn bit a ch ca Chng trnh x l

ngt tng ng m ch cn bit s hiu ngt. S hiu ny ch n mt phn t trongmt bng gi l bng cc vector ngt nm vng c a ch thp nht trong b nhv cha a ch ca Chng trnh con x l ngt. a ch btu ca mi Chngtrnh con c xc nh bi a ch on v a ch offset c t trc on.

- Hai a ch ny u l 16 bit (2 byte), nh vy mi a ch ngt chim 4 byte trongb nh. My tnh PC c 256 ngt khc nhau c nh s t 0 n 255 do vy di ca c bng do vy s l 256*4 = 1024. Bng vector ngt chim cc nh t ach 0 n 3FFh. S th t ca ngt bng s th t ca vector ngt. a ch caChng trnh x l s i c cha trong bng vc t ngt t a ch offset 4*(i-1)n 4*(i-1) + 3.

Mt s ngt thng dng

STT S hiungt

Chc nng STT S hiungt

Chc nng

1 00 Ngt chia cho 0 7 20H Kt thc Chng trnh

2 04 Ngt trn s 8 21H Gi cc hm ca DOS

3 08 Ngt thi gian 9 25H/26H c/ghi a4 09 Ngt bn phm 10 27H Kt thc nhng thng tr

5 10H Ngt phc v mn hnh 11 33H Ngt phc v chut

6 19H Ngt khi ng h thng 12 67H Qun l b nh m rng

(Tham kho thm Vi x l)

4.2. Qun l Processor

t vn Chng trnh khng th thc hin c nu n khng c np vo b nh, song ngay

c khi c np vo b nh nu n khng c quyn s dng Processor th vn khng th

thc hin c.- Processor: Ti nguyn phc v cho vic thc hin chng trnh. n v cng vic

giao cho processor phc v l tin trnh, nhiu tin trnh c th sn sinh t chngtrnh.

- Tin trnh: i tng m ta c th phn phi Processor cho n.

4.2.1. Processor vtl v Processor logicProcessor vt l: tt c cc h iu hnh thc hin song song u do mt Processor ca

h thng Processor vt l iu khin.


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Processor logic:ngi s dng nh gi hot ng ca Processor trn c s quan st vnh gi chng trnh ca mnh c thc hin nh th no. Processor m ngi s dngquan st v nh gi c gi l Processor logic - lin quan ti vic thc hin tin trnh.

Vi ch x l k tip n chng trnh (Tin trnh tun t): PVL PLGVi cc tin trnh hot ng song song quan tm cc chin lc iu Processor( iu

tin trnh mc Processor).Vn cn quan tm:

Nn to ra bao nhiu Processor logic l thch hp

di khong thi gian gn lin tc Processor vt l cho Processor logic l bao nhiuth hp l

Sau khi mt Processor logic ht quyn s dng Processor vt l th cn chn tin trnhno phn phi Processor vt l.

4.2.2. Phn phi ProcessorTrong ch a nhim, mi tin trnh c th thuc mt trong ba trng thi: Sn sng Thc hin Ngt

Trng thi Thc hin: Nu h thng ch c mt Processor th mi thi im ch c mttin trnh dnh c Processor thc hin lnh ca mnh. Tin trnh ny nm trong trngthi thc hin.

Trng thi Ngt: Nu tin trnh khng th thc hin tip c v b thiu mt vi iukin no tin trnh s nm trong trng thi ngt. Tin trnh gi ti mt mun nhngmun cha c np v nh v trong b nh. Khi tin trnh c th c lu tr ti bnh ngoi.

Trng thi Sn sng: Tin trnh c phn phi y ti nguyn (tr Processor): tintrnh nm trong trng thi sn sng, khi processor ri tin trnh s c thc hin.

Tin trnh c th ri b trng thi Thc hin bi mt trong ba l do: Tin trnh hon thnh mi vic cn thit, khi n tr li processor v

chuyn sang ch x l kt qu. T ngt: Tin trnh chuyn sang trng thi ngt khi n ch mi s kin no . Tin trnh s dng ht thi gian processor vt l dnh cho n v c chng

trnh iu chuyn n t trng thi thc hin sang trng thi sn sng (phnphi li ti nguyn h thng).

4.3.3.iu tin trnhMt trong nhng chc nng ca chng trnh iu l chn tin trnh thc hin

(chn tin trnh sn sng v phn phi processor vt l cho n).Mi tin trnh sn sng c gn mt th t u tin, th t ny c xc nh da vo

cc yu t: Thi im hnh thnh

Khi to Sn sng Thc hin End

Ngt


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Tng thi gian tin trnh c thc hin Thi gian ngi s dng d bo kt thc tin trnh. Tiu chun nh gi cht lng iu : Thi gian ch i x l thi gian mt

tin trnh trng thi sn sng ch c phn phi Processor vt l. Cc chin lc thng gp v c ch t chc ca cc chin lc

A. Ch mt dng xp hngNguyn tc: m bo cho mi tin trnh c phc v nh nhau, khng c mt tin

trnh no phi ch i lu hn tin trnh khc. nh gi cht lng iu ta c th da vo thi gian ch i trung bnh

ca cc tin trnh. Thi gian ch i ca cc tin trnh c tnh t khi tin trnh trng thi sn

sng ti khi tin trnh chuyn sang trng thi thc hin. Vi mi tin trnh ta o khong thi gian ny nhiu ln, khi c th tnh c

thi gian trung bnh. Kt hp vic o thc nghim v phn tch gii thut iu nh gi cht

lng iu c c thi gian ch i trung bnh chnh xc cho cc tintrnh.

Quan st v thng k thi gian ca tng tin trnh rt ra thi gian ch i trung

bnh ca h thng.a. Chin lc phc v bnh ng FCFS(First Come First Served)

m bo mi tin trnh u c mt thi gian ch i trung bnh nh nhau, cc tin trnhc phc v n khi n kt thc hoc khi phi chuyn sang trng thi ngt.

u im:

Processor khng b phn phi li Chi ph thp: khng phi thay i th t u tin iu

Nhc im: Tin trnh ngn cng phi ch nh tin trnh di Thi gian ch i trung bnh tng v hn khi h thng tim cn ti kh nng

phc v ca mnh Khi gp tin trnh b ngt, cc tin trnh khc s b xp hng lu.

b.Chin lc u tin nhng tin trnh c thi gian thc hin ngn nht SJN (Shortest JobNext)

Xc nh th t u tin iu trong qu trnh thc hin tin trnh ch khng phi lckhi to.

c im: Khng phn phi li Processor Thi gian ch i ca cc tin trnh ngn nh hn so vi phng php FCFS Thi gian ch i ca cc tin trnh di ln hn so vi phng php FCFS Khng d on c khi no tin trnh di c thc hin.

c. Chin lc u tin cc tin tr

nh c thi gian c

n li t nht SR

T (Shortest Remaining

Time)

Nhc im ca FCFS l cc tin trnh ngn phi ch i nh tin trnh di, vi SJN thkhng d on c khi no tin trnh di c thc hin. Khc phc cc nhc im ny: sosnh thi gian thc hin ca tin trnh di ang c thc hin vi thi gian thc hin tintrnh ngn c d bo trc xem xt u tin

Nu thi gian thc hin ca tin trnh di ang thc hin cn li l nh hn th tip tcthc hin tin trnh di, ngc li a tin trnh v trng thi ngt v thc hin tin trnh ngn.

d. Chin lc xp hng ln lt RR (Round Robin) phn phi li Processor


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Nguyn tc: mi mt tin trnh trong dng xp hng ln lt c phn phi mt lngt thi gian thc hin. Sau khong thi gian , nu tin trnh cha kt thc hoc khng rivo trng thi ngt th n c chuyn v cui dng xp hng: tin trnh xp hng vng trn.

Khi c mt tin trnh mi, n s c a vo dng xp hng vng trn v c t v tr c phc v ngay lp tc.

Vi cc tin trnh di: phn thnh m lp, lp th i tin trnh c phc v vi khongthi gian Ti, sau khi c thc hin, tin trnh cha kt thc hoc khng b ngt n cchuyn sang lp th i+1 vi thi gian phc v Ti+1 > Ti.

B. Chin lc nhiu dng xp hngDa vo thng tin do ngi s dng cung cp v kt qu phn tch ca h thng, phn

lp cc tin trnh v a ra chin lc phc v tng ng.Cc tin trnh c th c phn thnh cc lp: Tin trnh thi gian thc Tin trnh ca ch s dng tp th phn chia thi gian Tin trnh x l l

CU HI V BI TP

4.1. Anh ch hy cho bit trn h iu hnh ang dng hin s dng chin lc iu khintin trnh no? Cho v d minh ha4.2. So snh nguyn tc, u nhc im ca cc chin lc iu tin trnh trong ch mt dng xp hng.4.3. Xy dng chng trnh nhn 1 k t ch thng t bn phm v chuyn thnh k t chhoa.4.4. Xy dng chng trnh thng tr gim st cc ng dng thc hin trn h iu hnhWindows


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Chng V: H IU HNH NHIU PROCESSOR

5.1. H iu hnh nhiu ProcessorS kt hp ca cc Processor trong mt h thng tnh ton, s kt hp ca cc h thng

tnh ton n Processor.Mc ch:S chuyn mn ho cc Processor lm gim gnh nng x l Hot ng n nh v nng sut cao tin cy cao Lm cho cc ti nguyn c gi tr cao, mang tnh kh dngi vi bt k ngi

dng ngi dng no trn mng. Tng tin cy ca h thng nh kh nng thay th khi xy ra s c i vi mt

my tnh no

5.1.1. Cu hnh nhiu ProcessorTn ti nhiu phng thc kt ni hai hay nhiu Processor.S kt hp ca my tnh vi cc h thng truyn thng, c bit l mng vin thng

to ln m hnh tp trung cc my tnh n l c kt ni vi nhau cng thc hin cng

vic. Mi trng lm vic nhiu ngi dng, cho php nng cao hiu qu khai thc ti nguynchung t nhng v tr a l khc nhau (b nh, chng trnh, nhim v...)Cu hnh phn cp: Client/ Server: mt Processor ngoi vi v c th hot ng c lp

trong khi gii quyt nhim v ca mnh.c im:- Chng trnh d t chc

- Chng trnh iu khin khng phi sao chp nhiu ln.- Khng phi t chc kiu module vo/ra nhiu ln

- Thc hin ngt tng.

S lin kt mm linh hot: Cc processor c quan h bn ph thuc

- Mi processor x l tin trnh ca mnh t khi hnh thnh ti khi kt thc.- Cc processor c th lin h, trao i thng tin v chuyn giao tin trnh trc khi

n c bt u thc hin.

c im:

- Gim gnh nng x l ti mt processor

- Cc processor c th trao i tin trnh, c ch iu n ginS lin kt bnh quyn:Cc processor c coi nh tp cc ti nguyn cng loiThay cho vic thc hin tng chng trnh trn tng processor, phn chia cng vic

iu khin cho tt c cc processor. Nh vy mt tin trnh c th bt u processor nynhng c th kt thc processor khc.

c im:- Gim gnh nng x l ti mt processor

- Cc processor c th trao i tin trnh, c ch iu n gin- Kh nh gi kt qu thc hin tin trnh

5.1.2. H iu hnh nhiu processor:Tn ti mt h iu hnh c chc nng qun ly d liu, tnh ton v x l mt cch

thng nht: H thng nh vy gi l h iu hnh nhiu processor.

Vi cc tip cn:


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- Tp trung: Tn trng h iu hnh cc b c trn cc h thng tnh ton, h iuhnh nhiu processor c ci t nh mt tp cc chng trnh tin ch chy trnh thng.

- Phn tn: B qua h iu hnh cc b c trn cc h thng, ci t mt h iuhnh thun nht trn ton mng

Vi m hnh tp trung:

- Cung cp cho mi ngi dng mt tin trnh ng nht lm nhim v cung cp mtgiao din ng nht vi tt c cc h thng cc b c

- Tin trnh ny qun l c s d liu cha thng tin v h thng cc b v v ccchng trnh v d liu ca ngi dng thun tu: B x lnh

Dng cc lnh ca ngi dng ngn ng lnh ca h thng gi ti P thc hin

- c im: n gin, khng lm nh hng ti cc h thng cc b c Kh thc hin I/O

Vi m hnh Phn tn:

- M hnh tin trnh: Mi ti nguyn c qun l bi mt tin trnh no v hiu hnh iu khin s tng tc gia cc tin trnh

- M hnh i tng: Coi cc tin trnh v cc i tng, mi i tng c mt kiu,mt biu din v mt tp cc thao tc c th thc hin trn n

o Nh vy:o Tin trnh ca uses phi c php thao tc trn i tngo H iu hnh qun l vic thao tc ca tin trnh trn i tng.

5.2. H iu hnh phn tn (Distribute Operating System)

5.2.1. Khi nim:

Tp cc chng trnh phc v tp trung nh mt giao din qu trnh ng dng v hthng tnh ton nhm t c tnh hiu qu an ton, d s dng h thng tnh ton.

Chc nng ca h iu hnh :

- iu Processor- ng b gia cc qu trnh tng tc

- Qun l ti nguyn h thng- m bo iu khin truy nhp v bo v tnh ton vn h thng, phc hi v cung

cp giao din ngi dngQuan nim v h iu hnh:

- My o: Tru tng ho h thng my tnh (mc tiu thit k c bn)

- Qun tr ti nguyn : Phng tin t c mc chNh vy:- H iu hnh tp trung: Quan tm ti vic qun tr ti nguyn h thng

- H iu hnh phn tn: Tru tng ho my tnh

Vo thi im mi ra i: Cc h iu hnh c thit k tp trung chy trn cc hthng c mt hay nhiu b x l (Processor)

Vi tip cn mng my tnh ngy nay: Cc h thng lm trn phm vi rng, phn tn nhiu a im khc nhau i hi c ch qun l phn tn.


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5.2.2.c trng ca h iu hnh phn tn

a. So vi PCKh nng dng chung d liu:- Nhiu PC dng trn nhiu bn sao ca d liu ti nhiu ni, v vy chi ph cho vic

ng b qun l truy nhp v bo mt tn km- MSDOS: Dng trn mt s t cc bn d liu, chi ph gim

Kh nng dng chung thit b:- Mi PC phi trang b y cc thit b ngoi vi song nu c kt ni trong mi

trng MSDOS cc thit b ngoi vi c th c s dng chung bi nhiu ngidng trong h thng, nh vy tit kim v hiu qu

Kh nng truyn thng:

- Kt ni ca PC nh dch v mng vin thng, thi gian ch i c phc v lkhng an ton.

- Vi MSDOS: mi trng phn tnTnh linh hot:- Vic phn chia li ti nguyn gy ra chi ph tn km: lu chuyn ti liu, thit b, d

liu...- MSDOS: S dng cc chc nng chuyn bit ca h thng

b. So vih iu hnh tp trungTc :Nng lc k ton cao khi tp trung mt s b vi x l trn mt my tnh

Tnh kinh t: T sut gi c hiu nng cao

Tnh phn b: Lin kt cc ng dng trn cc my ring bitTnh n nh v tin cy: H thng vn lm vic khi mt my gp s cTnh m: C th tng bc m rng quy m h thng

c. Hn ch ca h iu hnh phn tn- Phn mm: i hi h iu hnh, cc ngn ng hnh thc, cc chng trnh ng

dng ph hp: thit k, ci t kh, phc tp- Vn mng: Thay th ton b h thng c

- Vn truyn thng: an ton d liu, lu lng ng truyn, qu trnh thay th khic s c.

- Vn bo mt: Gi thnh cao, kh s dng chung d liu, chng trnh

d. Yu cu thit k h iu hnh phn tnTnh trong sut

- Tnh trong sut vi ngi dng: ngi dng ngh rng h thng phn tn ch l mttp my tnh hot ng ch phn chia thi gian

- Tnh trong sut h thng: h thng trong sut i vi chng trnh, li gi h thngphi c thit k sao cho s c mt ca nhiu processor l khng th thy c tchng trnh

Th hin:- Trong sut v nh v:ngi dng khng th ni chnh xc cc ti nguyn nm

u (ti nguyn c m ho v tr)- Trong sut v nh x:tn ti nguyn khng thay i khi di chuyn t my ny sang

my khco Trong sut v lp li: h thng c th (v cn thit) lu mt s bn sao ca

cng mt ti nguyn m ngi dng khng bit


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o Trong sut ng thi: nhiu tin trnh c th cng truy nhp mt ti nguyn,cc tin trnh c th khng cn bit ti s c mt ca tin trnh khc

o Trong sut song song: nhiu hot ng song song c che i vi ngidng

o Trong sut li:c ch phc hi li trong h thng c che i vi ngidng

o Trong sut kch thc: cho php h hng m rng qui m dn dn ma khng

tc ng ti ngi dngo Trong sut v quan st: im nhn phn mm khng th thy c i vingi dng.

Tnh modul ho: H thng c phn chia lm nhiu modul nh cho php b sung, thayi d dng

Tnh kh m: qui m h thng thng xuyn thay i do cc yu cu nng cp

Tnh c lp, quy m: M rng quy m m nng lc h thng khng thay i

Tnh chu li:Thng xuyn sao lu phc hi li

5.3. Qun l ti nguyn trong h iu hnh phn tn

5.3.1. Qun l thit b, qun l File

Khi nim File: n v thng tin nh nht ca ngi dng, c qun l thng qua tnfile.

- Ngi dng phi l tr thng tin b nh ngoi v vy h iu hnh phi c vaitr sao cho ngi dng truy nhp thun tin

- Nhu cu dng chung (chia s) cc file d liu.

- Vn t ra i vi h thng qun l file: ngoi cc tnh cht v yu nh i vih qun l file trong h iu hnh tp trung, h qun l file trong h iu hnh phntn phi m bo:

- Tnh trong sut ca h thng- Dch v th mc

- Hiu nng h thng, tin cy- an ton.

Tnh trong sut- Tnh trong sut ng nhp: ngi dng c th ng nhp vo cc trm trong h

thng vi cng mt th tc ng nhp- Trong sut truy cp: Cc tin trnh chy trn h thng c cng c ch truy nhp vo

cc tp tin m khng cn xem tp l cc b hay t xa- S c lp v nh v tp tin: Cc tp tin c th c chuyn t v tr ny ti v tr

khc m khng lm thay i tn: trong sut i vi ngi dng- Tnh trong sut tng tranh:cc file c chia s bi nhiu ngi dng, vic truy

cp ti mt tp t mt tin trnh khng nh hng ti s thnh lp ca tin trnhkhc

- Trong sut lp: Cc tp c sao lu d phng cho php truy nhp ng b(ngi dng khng bit cc bn sao).

Thit k v thc hin h thng tp tin phn tni vi ngi dng, mt tp tin bao gm ba thnh phn logic:

- Tn tp v h thng tp- Cc thuc tnh- Cc n v d liu


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Cc tp v h thng tp

Cc tp c to ra bi ngi dng i km vi tn, khi truy nhp tp, tn tp s xcnh gi tr ID ca tp v gi tr ny cng l gi tr duy nht xc nh v tr vt l ca tp

Cc thuc tnh: Cc thng tin v quyn s hu, quyn truy nhp, dng tp, kch thc,du hiu thi gian

Cc n v d liu

n v d liu : Byte, khiC ch truy nhp:- Tun t: Con tr nh v tp c duy tr bi h thng cho php xc nh v tr n

v d liu k tip c truy nhp gia cc tin trnh- Trc tip (truyn thng khng lin kt): V tr n v d liu cho vic c, ghi l r

rng. C ch ny lin quan ti kch thc ca n v d liu, cc thao tc c ghiphi bao hm cc thng tin iu khin.

- Ch s: n v d liu c a ch ho bi ch s hay kho i km mi khi dliu.

Vn bo mtBo v d liu: khng mt thng tin khi c s c k thut hoc chng trnh thm

ch truy nhp bt hp lK thut bo v d liu cho h phn tn:

Phng php m ho d liu vi thut ton DBS- Kho b mt: Thut ton gii m- Kho cng khai: sinh m:

Kerberos: S xc nhn l ng ca cc thnh phn da trn c s tin tng vo thnhphn th 3 (mt khu)

Ch k in t: Xc nhn tnh nguyn bn m cc vn bn (Digital Signature)

5.2.2. Qun l b nhNgoi cc phng php qun l b nh nh trong h iu hnh tp trung, vn quan

tm trong vic qun l b nh h iu hnh phn tn l vic m bo tnh chia s b nh.Chia s b nh: Truy nhp b nh t xa:Vic truy nhp c thc hin ti mt nt xa

- Khi d liu xa c di chuyn ti nt cc b: truy nhp cc b

- Khi d liu xa c sao lu li ti nt cc b: truy nhp ng b

Cc phng thc- c t xa (Read remote): Khi d liu dng chung khng c di chuyn hay sao

lu, my trm gi yu cu ti my ch, my ch gi tr li v d liu cho vic c,v bo nhn cho vic ghi.

- c/ghi nh x (Read/write migrate): Nh vic truy cp ti mt khi d liu t xa

m khi d liu c di chuyn ti tin trnh yu cu. Tin trnh s cp nhp tibng nh x khi vt l - trang o ca d liu

5.2.3. Qun l tin trnhKhi nim v tin trnh: n v thc hin c nh nht thy bi ngi dng

Lung (Thread): n v thc hin c nh nht thy bi h iu hnh, c h iuhnh cp pht thi gian Processor.

Quan h gia tin trnh v lung:


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Tin trnh l khng gian a ch trong lung c thc hin. Hai tin trnh cngkhng gian a ch - hai lung thuc mt tin trnh.

Qun l tin trnh: vic qun l cc tin trnh thng qua cc khi iu khin tin trnh.

Khi iu khin: Bn ghi cha cc khi iu khin cc lung, cc cng thng tin , ccti nguyn h thng m tin trnh ang s dng, cc thng tin trng thi tin trnh: Sn sng,thc hin v ngt

Qun l lung: Khi iu khin lung:

B m lnh: PC- Con tr ngn xp: SP

- Tp cc thanh ghi: Rs- Trng thi: Flag

Cc chc nng qun l tin trnh v lung thng tin chia lm ba loi- Truyn thng: m bo s lin kt gia cc tin trnh

- ng b: m bo thc hin cc tin trnh ti u

- iu : m bo cc tin trnh s dng ti nguyn chia s ng n

Ci t lung:

Trong khng gian ngi dng: Khi lung gi mt th tc h thng n thc hin lin ktvo th vin ng. Th tc th vin ng kim tra xem c cn treo lung khng, nu cnn treo lung ny v chuyn iu khin cho lung khc.

Trong nhn h thng: Khi lung gi mt th tc h thng, n s c gn vo nhn hthng.

Truyn thng gia cc tin trnhM hnh truyn thng OSI: mi tng c mt chc nng ring, thng ip truyn gia hai

ng dng da trn giao thc, khi qua mi tng n c gn thm vng header.M hnh Cilent/ Server- Client truyn thng ip cho server yu cu dch v- Server thc hin dch v tng ng v gi thng ip tr li

Cc vn :

- nh v yu cu t Clinet no:- Gn cho mi Client mt a ch ID- Client chn a ch ngu nhin, thng bo c gi cho taat c cc Server

a tn Server vo Client khi chy chng trnh.

- Ch chuyn thng ip: kho, khng kho:o Kho: khi c mt thng ip c chuyn, tin trnh ca Client b treo v ch

cho ti khi c tr li hoc bo lio Khng kho: tin trnh vn tip tc thc hin cc cng vic khc

- Ch c bo m v khng bo m:

o C bo m: Server nhn c thng ip t Client n s phc p li Client bit.o Khng bo m: khi tin trnh gi thng ip, n khng c bo m l

thng ip n chM hnh truyn thng nhm:Nhm: tp cc tin trnh, v vy khi mt thnh vin nhn c thng ip tt c cc tin

trnh trong nhm u c th c chia s.

ng b cc tin trnhng b: m bo th t thc hin ng n ca cc lung, cc tin trnh


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ng b ng h thi gian thc:

Gi s c tp .OBJ trn mt my c bin dch t tp A.ASM trn mt my khc. Tmt my th ba, ngi

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17303 - Bai Giang Nguyen Ly He Dieu Hanh