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I.

Li ni u ........................................................................................... Error! Bookmark not defined. Lch s hnh thnh......................................................................................................................... 3 H iu hnh Amoeba ................................................................................................................... 4

II. Tng quan H iu Hnh Amoeba 1 2

III. Qun l tin trnh H iu Hnh Amoeba..5 1 2 IV. V. Tin trnh....................................................................................................................................... 5 Qun l tin trnh .......................................................................................................................... 8 Kt Lun.11 Ti Liu tham kho.12

1 Nhm H iu hnh tin tin Lp Khoa hc my tnh K51

I.

Li ni u

Trong nhng nm qua, cng vi s pht trin nh v bo ca khoa hc k thut, ngnh cng ngh thng tin cng bin i khng ngng p ng vi mi nhu cu mi ca con ngi. Trong s nhng pht minh v i nht ca th k trc, mng my tnh ( Computer Network) l mt h thng em li nhiu li ch to ln nht cho nhn loi. Mng my tnh ngy nay cho php hng t my tnh trntri t v ang kt ni v lm vic vic vi nhau vi tc cao ( t vi chc n hng nghn kbps). iu k diu trn tr thnh hin thc v ngy cng pht trin mnh m hn na ch khi c mt nhn t quan trng lm nn tng c s l thuyt cho chng c nghin cu. chnh l nhng l thuyt nghin cu lin quan n h phn tn. Nh c l thuyt h phn tn, m cc vi x l n l - nm trn cc my tnh n l (km theo l cc thit b ngoi vi v cc thit b u cui lm vic t xa)- m chng vn thng c gi l cc h thng tp trung(Centralized Systems) c kt ni li, lm vic trn nhiu giao thc, nhiu kiu kt ni v trn nhiu lnh th khc nhau. V khi cc h thng tp trung c kt ni li theo nhiu nhm, nhiu cch thc khc nhau v lm vic da trn nhng nguyn l c bn ca h phn tn th chng s c gi l cc h thng phn tn (Distributed Systems), in hnh nht ca cc h phn tn chnh l mng my tnh m chng a ang s dng ngy nay.

2 Nhm H iu hnh tin tin Lp Khoa hc my tnh K51

II.

Tng quan H iu Hnh Amoeba

1. Lch s hnh thnh H iu hnh Amoeba: H iu hnh Amoeba l mt h iu hnh phn tn c pht trin bi Gio s Andrew S. Tanenbaum v nhm sinh vin ca ng gm Frans Kaashock, Sape J. Mullender, Robbert van Renesse, Leendert van Doorn, Kees Verstoep ti i hc Vrije , Amsterdam, Netherland vo nm 1981.

Phin bn u tin ca h iu hnh c ra i vo nm 1983 (Version 1.0) phin bn gn y nht c cng b l Amoeba Version 5.3 vo nm 1996, h tr nhiu kin trc vi x l nh 68030, i80386, i486, SPARC, Sun 3/60...

3 Nhm H iu hnh tin tin Lp Khoa hc my tnh K51

2. Mc tiu ca h iu hnh Amoeba: Amoeba c xy dng t nhng scratch, khng da trn bt k mt h iu hnh no trc v s dng ngn ng Python xy dng nn Platform ny. N c giao din tng tc vi ngi dng ging nh UNIX Timesharing System. Ban u Amoeba c xy dng l 1 h iu hnh chia s thi gian chy trn my trm trong mng my tnh. Mt trong nhng mc ch c bn ca nhng ngi pht trin H iu Amoeba l mun thit k mt h thng phn tn cho php ngi dng c th ng nhp vo h thng mt cch trong sut, c ngha l n i nhng phn phc tp ca h phn tn i vi ngi dng, ngi dng Amoeba khng cn tp trung vo s lng Processors trong h thng cng nh h c th khng bit a ch ca nhng my client khc v servers (ging nh Filesystem server). im phn bit H iu hnh Amoeba vi cc h thng phn tn khc l Amoeba khng c khi nim mthome machine.Bn cnh Amoeba cn cung cp cho ngi dng mt mi trng phn loi v tnh ton song song. Mt h thng Amoeba th mt chuwong trnh hay dng lnh c th s dng nhiu processors tng hiu nng tnh ton. Ngi dng n gin ch cn yu cu mt thao tc v Amoeba OS s quyt nh cch tt nht thc thi yu cu . Amoeba s quyt nh nhng processor no l thch hp cho yu cu thc hin yu cu thm na ngi dng c th t to mt mi trng c th lm vic tin li hn da trn mi trng m Amoeba cung cp. V d nh Amoeba h tr cho deverlopment t to mt chng trnh song songv d nh Ngn ng lp trnh song song Orca

4 Nhm H iu hnh tin tin Lp Khoa hc my tnh K51

Ameoba cn cung cp cho mt giao thc mng thc thi tnh ton hiu nng cao trn mng l FLIP (Fast Local Internet Protocol). Khi FLIP c pht trin th khng mt protocols no vo thi im c th h tr cho h phn tn, FLIP thc thi rt gn gng, n gin v hiu qu vic truyn thng, k ni gia cc nodes trong h thng. Trong bo co ny chng ta s tm hiu v vn qun l tin trnh trong h iu hnh Amoeba. III. Qun l tin trnh trong Amoeba:

1. Tin trnh trong H iu hnh Amoeba Mt Process l mt i tng trong Amoeba. Thng tin v 1 process trong Amoeba c cha trong 1 Process Capability v c m t chi tit trong 1 cu trc d liu c gi l Process decriptor, th m thng c s dng to process v dng process hoc di tr process. Process Decriptor bao gm 4 thnh phn sau:

5 Nhm H iu hnh tin tin Lp Khoa hc my tnh K51

Process Descriptor Host Descriptior cung cp nhng yu cu cho h thng ni m process phi chy bi nhng m t nhng g m my c th chy Capabilities bao gm kh nng ca process vi th m mi client cn v quyn hn vi 1 handler th m giao tip vi signals v gii phng process. Segment m t layout ca khng gian a ch mc thp. Thread m t trng thi ca mi thread mc thp trong process v cc thng tin ca n nh IP, Stack Amoeba h tr m hnh n thread, khi 1 process khi ng n s c t nht mt thread, s lng thread l bin ng, trong qu trnh thc thi th process c th to thm thread v c th ngt cc thread ang tn ti. Tt c cc threads c qun l bi kernel. im tin li ca thit k ny l 1 thread s lm 1 RPC 6 Nhm H iu hnh tin tin Lp Khoa hc my tnh K51

( Remote procedure call ), kernel c th ngn chn thread v lp lch cho thread khc trong cng process nu n sn sng.

Ba phng php c Amoeba cung cp cho vic ng b thread l Mutexes: ging nh mt c nh phn, c th cho 1 trong 2 trng thi l : locked hay unlocked. Khi c gng locked mt unlocked mutex s lm cho thread b kha sau qu trnh gi thead vn tip tc. Nu c gng kha 1 mutex th n s ngay lp tc b locked l nguyn nhn khi gi thread ngn chn cho n khi 1 thread khc unlock mutex. Semaphores: l cch th hai ng b threads (m c Semaphores). Chm hn phng php mutexe nhng i khi cn phng php ny. 1 semaphore khng th ph nh v d nh khi c gng gim 1 zero semaphore s l cho vic gi thread b kha cho n kh 1 thread thc thi hnh ng up semaphore.

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Signals: l nhng ngt khng ng b gi t 1 thread n thread khc trong cng 1 process. Tn hiu c th c tng, bt ly hoc b qua. Ngt bt ng b gia cc process s dng dng h thng ang chy. Khi mt process c to th process cha ca n s c trao quyn i vi process con va c to nh quyn suspended, restarted, signaled, or destroyed. 2. Qun l tin trnh trong m hnh Amoeba Distributed System: Qun l tin trnh trong Amoeba c chia lm 3 mc Qun l bi Process Servers y l nhim v ca Microkenel Qun l bi Library procedures c hot ng nh 1 interfaces Qun l bi server ni quyt nh process no s c chy. Hu ht tin trnh s c to ra v qun l bi cc b bin dch dng lnh, nhng c mt s tin trnh cng c th to theo mt cch mi. Tt c u c yu cu l kh nng cho php truyn thng vi Amoeba Kernel. Hu ht ngi s dng s c th truy cp n cluster to ra kh nng cho Amoeba Kernel chy c trn trm lm vic ca chnh chng. iu ny c ngha rng, ngi s dng c th to ra mt tin trnh mi trn trm lm vic ca chnh chng. Kh nng cho vic to ra tin trnh trn b x l chung s c c trng bi dch v Processor Pool m s hot ng nh l mt tc nhn cho chng trnh ang chy thay cho tin trnh ca ngi s dng. S cn li c lu tr bi dch v Processor Pool khi n dng b x l chung mt cch thn trng.

8 Nhm H iu hnh tin tin Lp Khoa hc my tnh K51

Processor pool Mc d cluster him khi di chuyn n mt host mi sau khi khi ng, nhng di tr l mt khi nim trung tm trong c ch qun l tin trnh ca AMOEBA. Bi v l vic load cluster mi trong b nh, thc hin check-point, v g li t xa. Tt c tng t nh l s di tr cluster. Thc t, nu chng ta c th di tr mt cluster t mt my ny sang my khc th vic download, checkpoint, g li s l n gin. Phn load cn li bi s di tr cluster l khu vc t c hiu v n khng r rng khng bit n rt hu ch vi cc loi hin ti ca trm lm vic v mng. Cho v d, vic di tr 5MB cluster s mt ti thiu 7s, bi v l thi gian mt giao thc truyn nhanh copy ni dung b nh trn 10Mbit Ethernet. Chng trnh 5MB l khng ph bin, c bit nh l ng c vin cho s di tr: Nhng cluster c cng thng rng nh th. Do s di tr l kh t, v li ch ca hot ng di tr phi ln xng ng vi s tr gi trn.

9 Nhm H iu hnh tin tin Lp Khoa hc my tnh K51

Mc d nh th, nhng chng ta tin tng rng di tr hu ch. Khi mt owner ca trm lm vic log off vo bui ti, trm lm vic c th tr thnh Pool Processor v to dch v thc thi tin trnh cho phn cn li ca h thng. Tuy nhin, khi owner quay tr li vo bui sng v log on, th cluster khch ang chy c th b nh bt ra bi vic di tr chng sang mt trm lm vic khc. Kernel thc thi c ch di tr cluster. Chng khng thc thi chnh sch, s quyt nh di tr mt cluster v ni di tr n c thc hin trong cp cao ca dch v. Chng ta s khng i theo vic quyt nh s lm nh th no. Tin trnh m ra lnh di tr s c gi l Process Server. Khi mt cluster di chuyn t mt my ny n my khc, kernel mt my c to ra ni dung b nh v nhn cluster ca cluster sn sng n kernel ca my mi. Kernel trn my mi ti cluster vo trong b nh v khi ng n. Chng ta s gi hai kernel ny l Old Host v New Host. V d di tr cluster t im m Process Server quyt nh di tr cluster n New Host. Processor phi thit lp gii quyt cc tn hiu cluster nh l g li cluster. u tin, Process Server gi tn hiu n cluster, ci m lm cho Old Host ng bng n trong track ca n v gi nhn cluster n Process Server (Process Server hot ng nh l b g li cho cluster .) Sau , Process Server gi nhn cluster n New Host trong mt yu cu RunCluster. New Host, khi n nhn yu cu RunCluster th s to phn on cn thit, khi to chng bi vic gi yu cu Seg_Read n Old Host v sp xp chng vo mt khng gian a ch cluster mi. C hai client (New Host) v server (Old Host) c th gi v nhn trc tip m khng cn sp xp b nh, do ni dung b nh c th c copy trn Ethernet vi tc tt nh trn (khong MB/s) 10 Nhm H iu hnh tin tin Lp Khoa hc my tnh K51

Khi tt c ni dung ca phn on c copy, New Host khi ng cluster v gi mt reply c cha dung lng cluster mi n Process Server . Sau , Process Server xa cluster c ng thi yu cu DeleteCluster n Old Host. Ch rng, trong khi di tr ang tin hnh, cluster tn ti trn old host ca n vi iu kin ng bng. Do , Kernel phi reply n tt c message cho cluster ng bng vi 1 message Hy th li ln na, Cluster ny ang b ng bng. Sau khi cluster b xa, message ca chng s i li trong mt vi im, v sau kernel s reply tng t nh Cng ny khng c trong a ch ny. Tip theo, sender thc hin hot ng nh v tm ra pha mi ca cluster, v qu trnh truyn thng s c thit lp li. Giao thc cho vic gii quyt giao dch message trong sut qu trnh di tr l phc tp hn miu t trn. m bo ng ngha at-most-once ca giao dch message Amoeba, client v server cn s dng cng truyn thng duy nht hot ng nh v c th khng chu thua a ch ca mt server sai. IV. Kt Lun H iu hnh Amoeba tuy cha c ng dng rng ri nhng vi u th l min ph v m ngun m , Amoeba ang l mt h iu hnh phn tn tim nng trong vic nghin cu khoa hc, tnh ton song song trong tng lai. Cui cng do thi gian nghin cu cn cha c nhiu cha c dp thc hnh trn h iu hnh Amoeba nn bo co ca chng em cn nhiu thiu xt mong thy ch dn thm cho chng em . Nhm chng em cng xin cm n thy gio Tun Anh hng dn v gip v ti liu chng em hon thnh bi tp ln mn hc ny. Nhm sinh vin 11 Nhm H iu hnh tin tin Lp Khoa hc my tnh K51

V.

Ti liu tham kho http://amoebaos.org/ http://en.wikipedia.org/wiki/Amoeba_distributed_operating_system http://staff.um.edu.mt/csta1//courses/lectures/csm202/os22.html http://www.cs.vu.nl/pub/amoeba/ Distributed_systems_principles_and_paradigms_prentice_hall_2002

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Phn cng cng vic:TT 1 2 3 H tn Nguyn Th Thu H Cao Minh Qunh Nguyn Th Minh Cng vic Tng quan h iu hnh AMOEBA Qun l tin trnh + Bo co Di tr tin trnh + Bo co

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