tim hieu ve dien toan dam may doc

7/28/2019 Tim Hieu Ve Dien Toan Dam May Doc

1/31

CNG:

TI : TM HIU V IN TON M MYI.IN TON M MY.

1.1. Khi nim.

1.2.Cc c im ca in ton m my

1.3 u v nhc ca m hnh "in ton m my"

1.4.S cn thit ca in ton m my.

II.HOT NG CA IN TON M MY.

2.1.Kin trc ca ng dng in ton m my.

2.2.Kin trc ca my ch.

2.3.Map Reduce.

2.4.Hadoop.

III. IN TON M MY XU HNG CNG NGH MI TI VIT NAM.

IV. IN TON M MY CA MICROSOFT.

V. TNG KT.

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I. IN TON M MY

1.1. Khi nim.

in ton m my (Thut ng ting Anh: Cloud Computing, hay cn bit n

vi tn gi in ton my ch o) l m hnh my tnh da trn nn tng pht trinca Internet.

in ton m my l s nng cp t m hnh my ch mainframe sang m

hnh cleint-server. C th, ngi dng s khng cn phi c cc kin thc v chuyn

mc iu khin cc cng ngh, my mc v c s h tng, m cc chuyn gia trong

m my ca cc hng cung cp s gip thc hin iu .

Thut ng "m my" y l li ni n d ch mng Internet (da vo cch

c b tr ca n trong s mng my tnh) v nh mt lin tng v phc tp

ca cc c s h tng cha trong n. m hnh in ton ny, mi kh nng lin quan

n cng ngh thng tin u c cung cp di dng cc "dch v", cho php ngi

s dng truy cp cc dch v cng ngh t mt nh cung cp no "trong m my"

m khng cn phi c cc kin thc, kinh nghim v cng ngh , cng nh khng

cn quan tm n cc c s h tng phc v cng ngh .

V d nu mt website c cha trn mt my ch, ngi dng phi la chn

h iu hnh ci t (Linux/Windows/Mac), tin hnh cc thit l p my ch v

website c th hot ng. Tuy nhin, nu trang web c cha trn m my, ngi

dng s khng cn phi thc hin thm bt c iu g khc. iu ny cng m bo

yu t u t v phn cng c gim ti mc ti a.

S in ton m my, vi cc dch v c cung cp nm bn trong m

my c truy c p t cc my tnh bn ngoi.

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Cng sut x l nhanh hn do ti nguyn c t p trung. Ngoi ra, ngi

dng khng cn phi u t v ngun nhn lc qun l h thng.

Kh nng khai thc v hiu sut c ci thin hn 10-20% so vi h thng

my tnh c nhn thng thng.e. Vi tin cy cao, khng ch ginh cho ngi dng ph thng, in ton

m my ph hp vi cc yu cu cao v lin tc ca cc cng ty kinh doanh v cc

nghin cu khoa hc. Tuy nhin, mt vi dch v ln ca in ton m my i khi

ri vo trng thi qu ti, khin hot ng b ngng tr. Khi ri vo trng thi ny,

ngi dng khng c kh nng x l cc s c m phi nh vo cc chuyn gia t

m my tin hnh x l.

f. Kh nng m rng c, gip ci thin cht lng cc dch v c cung cp

trn m my.

g. Kh nng bo mt c ci thin do s t p trung v d liu.

h. Cc ng dng ca in ton m my d dng sa cha hn bi l chng

khng c ca t c nh trn mt m tnh no. Chng cng d dng h tr v ci

thin v tnh nng.

i. Ti nguyn s dng ca in ton m my lun c qun l v thng k

trn tng khch hng v ng dng, theo tng ngy, tng tun, tng thng. iu ny

m bo cho vic nh lng gi c ca mi dch v do in ton m my cung cp

ngi dng c th la chn ph hp.

1.3.2.Nhc im: Tuy nhin, m hnh in ton ny vn cn mc phi mt s nhc

im sau:

a. Tnh ring t:

Cc thng tin ngi dng v d liu c cha trn in ton m my c mbo c ring t, v liu cc thng tin c b s dng v mt mc ch no khc?

b. Tnh sn dng:

Liu cc dch v m my c b treo bt ng, khin cho ngi dng khng

th truy c p cc dch v v d li u ca mnh trong nhng khong thi gian no

khin nh hng n cng vic?

c.Mt d liu:

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Mt vi dch v lu tr d li u trc tuyn trn m my bt ng ngng hot

ng hoc khng tip tc cung cp dch v, khin cho ngi dng phi sao lu d liu

ca h t m my v my tnh c nhn. iu ny s mt nhiu thi gian. Thm ch

mt vi trng hp, v mt l do no , d liu ngi dng b mt v khng th phchi c.

D liu cha trn cc "m my" s phi giao ph ton b"s phn" cho "m my

d. Tnh di ng ca d liu v quyn s hu:

Mt cu hi t ra, liu ngi dng c th chia s d liu t dch v m my

ny sang dch v ca m my khc? Hoc trong trng hp khng mun tip tc sdng dch v cung cp t m my, liu ngi dng c th sao lu ton b d liu ca

h t m my? V lm cch no ngi dng c th chc chn rng cc dch v

m my s khng hy ton b d liu ca h trong trng hp dch v ngng hot

ng.

e.Kh nng bo mt:

Vn t p trung d liu trn cc m my l cch thc hiu qu tng

cng bo mt, nhng mt khc cng li chnh l mi lo ca ngi s dng dch v

ca in ton m my. Bi l mt khi cc m my b tn cng hoc t nh p, ton

b d liu s b chim dng. Tuy nhin, y khng thc s l vn ca ring in

ton m my, bi l tn cng nh cp d liu l vn g p phi trn bt k mi

trng no, ngay c trn cc my tnh c nhn.

1.4 S cn thit ca in ton m my.

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in ton m my c kh nng s m ra nhng gi tr v i cho cc ngun lc

ngoi (Outsourcing) ca ngnh CNTT v lm thay i b mt ca ngnh dch v

CNTT truyn thng.

Di y s l nhng g ngnh cng nghip Outsourcing ang phn ng tng

tc vi s pht trin ca in ton m my.

Cc hp ng dch v Outsourcing truyn thng lun mang nhng ni dung kh

r rng vi cc my ch, cc trung tm d liu, mng li, cc ch tiu k thut, hiu

sut cng vic v dng m sn phm. S xut hin ca in ton m my li ang

lm thay i tt c nhng iu nh s xut hin ca cc dch v CNTT nng ng

nh mt c s cn thit cho nhng vin cnh cng ngh dnh cho doanh nghip.

Nh cc dch v m my in ton, nhiu n v CNTT sn lng i trc mt

bc hn trong vic to ra cc ty bin: Chng gip cc hng CNTT dn loi b c

nhng chi ph vn kh tn km t c s h tng n cc phn mm tip cn khchhng v nhng vn trung gian khc. V h qu l, in ton m my ang lm thay

i hon ton b mt ca cc dch v CNTT truyn thng.

Susan Tan, gim c dch v CNTT v nghin cu ngun lc ca Gartner cho

rng: in ton m my l bc chuyn c bn ca cc cng ty trong vic chi tin

v tip cn cc dch v CNTT. Trn thc t, Gartner d on cho n nm 2012, 20%

cng vic kinh doanh s l o v khng c bt k ti sn CNTT no. y s l ngi

thay i cuc chi dnh cho cc nh sn xut dch v Outsourcing, t cc nh cung

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cp v t vn dch v onshore n dch v thu ngoi, cc nh tch hp h thng n

cc nh sn xut mi ring bit, nhm lm cuc chi tt hn hoc xu i.

Phil Fersht, sng lp vin ca cng ty t vn dch v thu ngoi Horses for

Sources cho rng:Nu in ton m my ch l mt ngnh khai thc cc c s h

tng t , rc ri v khng thn thin vi mi trng trong , Amazon v cc cng

ty khc phn phi cc nng lng in ton, th in ton m my n gin ch l

ngnh cung cp cc ch li v c s h tng. Tuy nhin, nu cc d liu v trnh

ng dng c lu gi bn ngoi m my, ngi s dng liu c cn phi t mnhqun l chng na khng? Ngi s dng c tht s cn phi t c cc li ch

cnh tranh i cng vi vic thc hin cc hp ng bo him? Hay n lc tm

kim cc nh cung cp dch v c chc nng qun l trnh ng dng, c s h tng c

lin quan v thc hin cc giao dch cha?

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Fersht gi cc dch v m my l nn tng cho cc gii php ngun dnh cho

doanh nghip th h k tip. ng tin rng cc dch v m my s lm cho qu trnh phn

phi truyn thng ca cc dch v CNTT hiu qu hn v tit kim chi ph hn. Chng

cng gip to ra mt c cu phn phi cho cc dch v gia cng thc s. Th h dch v

thu ngoi mi ny c kh nng m ra nhng gi tr to ln cho khch hng

II. HOT NG CA IN TON M MY

2.1. Kin trc ca ng dng in ton m my.

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Chng ta bit rng in ton m my l mt t hp tnh ton da trn cc thit

b h tng phn cng trong mt m my ca nh cung cp dch v. H tng phn

cng bao gm cc sn phm my ch cha d liu nh c kt ni li vi nhau nh

mt h thng phc v cho vic lu tr v x l d liu v cc ng dng tnh ton trn

cc ti nguyn khc. in ton m my gi mt ng dng chy trn my ch o nh

l n ang chy ti ch trn h tng phn cng phn tn trong m my. Nhng my

ch o c to ra theo nhng cch m nhng tha thun dch v (SLA) khc

nhau v s tin cy u c m bo. C th c nhiu thc th khc nhau ca cng

mt my ch o truy cp vo nhng phn sn sng ca c s h tng phn cng. iu

ny m bo rng c nhiu bn sao ca cc ng dng, khi xy ra li chng sn sng

khc phc. My ch o phn tn qu trnh x l vo c s h tng phn cng v sau

khi qu trnh tnh ton c hon thnh chng s tr v kt qu. Qu trnh ny cn cmt phn mm hoc h iu hnh x l cng vic qun l h thng phn tn, ging

nh k thut tnh ton li, gip qun l cc yu cu khc nhau n my ch o. C

ch ny s m bo vic to ra nhiu bn sao v c vic bo v s thng nht d liu

c lu trn c s h tng. ng thi h iu hnh cng c th t iu chnh nh

l khi gp qu ti cc tin trnh, phn chia x l hon thnh p ng yu cu. H

thng qun l cng vic nh vy c che du vi ngi dng, hay ni cc khc l n

vi ngi dng. S c lp vi ngi dng th hin ch n x l v tr v kt qu

t c, ch khng cn phi quan trng n u v n thc hin iu bng cchno. Ngi dng tr tin trn lu lng s dng h thng, nh ni dch v c

tnh bng chu k ca CPU hoc byte. Thc t s tin m khch hng phi tr thng

c tnh da vo lu lng dng CPU trn mt gi hoc s Gb d liu di chuyn

trong mt gi.

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2.2. Kin trc my ch:

in ton m my c to thnh bng cch s dng ti nguyn vt l ln t

nhiu my ch trong m my ca nh cung cp dch v. y l mt ng dng ca

nguyn tc kt hp vo trong bi ton cn mt h thng tnh ton ln m thit b hocc s vt cht khng cho php nn chng ta cn phi ghp nhng thit b, nhng h

thng nh li vi nhau tr thnh mt h thng ln p ng nhng nhu cu ln hn

cho ngi s dng trong nhng h thng yu cu tnh ton v lu tr ln . Nh ni

bn trn, dch v v ng dng ca in ton m my da trn my ch o c thit

k t ti nguyn gp li ny. C hai ng dng (hoc h iu hnh) s gip qun l cc

th hin trn my trong m my, cng nh qun l tt c cc ti nguyn ca cc th

hin my ch o. y l mt ng dng nguyn l tch khi vo trong h thng in

ton m my nhm tch bit phn cng phc tp ca h thng vi giao din bn

ngoi. Nhm to ra mt giao din ngi dng n gin, d s dng hn so vi phn

cng phc tp bn di v cng l tch bit giao din ngi dng vi h thng

phn cng, khi ngi dng ch cn quan tm n nhng ng dng m hc cn ch

khng cn quan tm n phn cng bn di c thc hin nh th no. ng dng

th nht l Xen hypervisor cung cp cc lp tru tng gia phn cng v h iu

hnh o, nh vy s phn tn ca cc ti nguyn v tin trnh c qun l ging nh

l ang thc hin trn mt my. ng dng th hai cng c s dng rng ri l h

thng qun l my ch o Enomalism, n c s dng qun l h tng phn cng

nn tng.

Khi Xen s dng cho cc lp o ca cc c s h tng my ch, mt lp phn

mm l Xen hypervisor c ci t gia my ch v h iu hnh. N cung cp

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mt lp tru tng cho php mi server vt l c th c chy nh l mt hoc nhiu

my ch o, tch ring h iu hnh v cc ng dng ca n khi lp phn cng vt l

bn di. Xen hypervisor l mt cng ngh m ngun m, c cng tc pht trin

bi Xen v cc k s ca hn 20 cng ty ni ting v trung tm d liu c tnh cht imi bao gm : AMD, Cisco, Dell, HP, IBM, Intel, Mellanox, Network Appliance,

Novell, Red Hat, SGI, Sun, Unisys, Veritas, Voltaire, and Citrix. Xen c ng k

bi GNU General Public License (GPL2) v c s dng khng c thay i v m

ngun v nh dng i tng. Xen Hypervisor cng c bit ngn - t hn 50.000

dng m. V vy chi ph dch m code rt thp v hiu sut gn ging nh trn my

nguyn thy. Xen ti s dng cc trnh iu khin thit b hin c (i vi c hai loi

l m v ng m ngun) t Linux, lm cho thit b qun l d dng. Hn na Xen rt

mnh m iu khin li v bo v c ngi dng v hypervisor khi cc vn vi

cc li t cc driver c hi.

H thng qun l my ch o Enomalism l mt nn tng h tng c s my

ch o hon chnh. Enomalism qun l nh hng gia cc ti nguyn trong h thng.

Enomalism c th s dng dn cc lung tnh ton vo m my ging nh l lung

t khch hng c i vo thc hin tnh ton trn mt my ch t xa. N mang tt c

nhng tnh nng nh: trin khai k hoch tnh ton, cn bng ti, trnh xung t ti

nguyn Enomalism cng l mt ng dng m ngun m, n c mt giao din ngidng da trn nn web rt n gin v d s dng. N c kin trc tng phn d dng

cho php to v thm vo h thng cc b sung v cc tin ch cn thit cho vic s

dng. N h trin khai t chc phn tn v to cc ng dng da trn tng quang

chung. N h tr qun l cc trng o khc nhau gm KVM/Qemu, Amazon EC2

and Xen, OpenVZ, Linux Containers, VirtualBox. N c ch phn quyn ngi

dng v t quyn truy cp.

2.3. Map Reduce.

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Map Reduce l mt m hnh lp trnh, c Google pht trin vo nm 2003,

h tr cho qu trnh tnh ton song song trn s lng tp cc d liu cc ln (vi t

byte) lu tr cc cm my tnh thnh phn trong m my in ton. Trong m hnh

ny, ngi dng nh ngha mt hm map tnh ton mt cp kha/gi tr u vo vto nn mt tp cc cp kha/gi tr tm thi, sau hm reduce s gom nhm tt c

nhng gi tr tm thi no c chung kha li vi nhau cho ra kt qu mong mun. Rt

nhiu cc tc v trong i sng thc c th c thc thi bng m hnh ny,chng ta

s xem xt c th hn phn sau.

Chng trnh c vit theo kiu chc nng ny c song song ha mt cch

t ng v c thc thi trn mt cm ln cc my tnh hng ha (cc my tnh

thnh phn cu to nn m my in ton). H thng khi chy s quan tm chi tit

phn vng ca d liu u vo, lp lch qu trnh thc thi chng trnh thng qua mt

tp cc my tnh thnh phn, x l li v qun l cc kt ni ni gia cc my tnh

thnh phn. iu ny cho php cc lp trnh vin ngay c cha c bt k kinh nghim

no trong cc h thng song song v phn tn u c th d dng ti u ha cc ti

nguyn ca mt h thng phn tn ln

Trong vng vi nm trc y, cc k s ca Google phi khi to hng trm

cc qu trnh tnh ton dnh cho cc mc ch c bit trn s lng ln cc d liu

th nh cc d liu mc ni, nht k cc trang web yu cuCc qu trnh tnh ton

ny dng cho nhiu mc ch khc nhau nh tm tt s lng cc trang c mc

ni bi tng host, tnh tn s truy xut ca 1 trang web, tm ra tp cc cu truy vn

c dng nhiu nht trong ngyHu ht cc tnh ton ny u khng phc

tp,nhng d liu u vo thng rt ln v qu trnh tnh ton cn phi c phn tn

cho hng trm ngn my nhm c th thc thi trong khong thi gian cho php. Ccvn v vic song song ha tnh ton,phn tn d liu v qun l li lm cho cc

qu trnh tnh ton vn n gin ny tr nn v cng phc tp.

gii quyt vn , cc k s ca Google thit k mt m hnh tru tng

cho php chng ta din t qu trnh tnh ton ny mt cch n gin nh vn d ca

n, ng thi che du i cc chi tit phc tp trong vic song song ha, chp nhn li,

cn bng np, phn tn d liu trong mt th vin ring. S tru tng ha ny c

ly tng t 2 thnh phn c bn l map v reduce trong Lisp v nhiu loi ngn

ng lp trnh hm khc. Chng ta c th nhn thy rng trong hu ht cc qu trnh

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tnh ton ca chng ta u bao gm mt thao tc map, nh x cc u vo vi cc gi

tr ca bn ghi thc hin vic tnh ton cc gi tr thnh 1 tp cc cp kha/gi

tr tm thi, sau ta li to thm mt thao tc reduce, thu gn cc gi tr m c cng

key li vi nhau v cho ra kt qu.Vic s dng m hnh hm chc nng map vreduce cho php chng ta c th thc thi song song cc tnh ton ln d dng v c th

s dng qu trnh thc thi li nh mt c ch chp nhn li.

Cc th mnh chnh ca phng php ny l cung cp cho chng ta mt giao

din n gin v mnh m, cho php song song ha v phn tn d liu trong cc php

ton ln mt cch t ng, gip cho ta thu c hiu nng cao nht trong s lng ln

cc cm my tnh thnh phn ca m my in ton. phn sau chng ta s ln lt

xem xt m hnh lp trnh c bn ca MapReduce v mt vi v d n gin

M hnh lp trnh

Qu trnh tnh ton nhn mt cp gi tr u vo gm kha/gi tr, v tnh ton

cho ra mt tp cc cp kha/gi tr u ra. Ngi dng s dng th vin MapReduce

din t qu trnh ny thng qua hai hm l Map vReduce.

Map l hm c nh ngha bi ngi dng, nhn mt cp gi tr u vo v

to ra cc cp gi tr trung gian.Th vin MapReduce nhm tt c cc gi tr trung gian

c lin quan ti key I li vi nhau v chuyn n cho hm Reduce.

HmReduce cng c vit bi ngi dng, chp nhn key I v cc tp gi tr

trung gian ca key I ny. Sau tin hnh hp nht cc gi tr ny thnh mt tp cc

gi tr nh hn nu c th. Mt ln na nguyn tc kt hp li c s dng trong h

thng in ton m my nhm phc v cho thut ton gii quyt yu cu bi ton, sau

khi chia nh cc chng trnh ln thnh cc phn nh thc hin tnh ton mt cch

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song song nhm lm gim thi gian thc hin mt bi ton th h thng tin hnh kt

hp cc kt qu tnh ton t cc tin trnh nh song song li vi nhau a ra mt kt

qu tnh ton thng nht ca chng trnh tnh ton m ngi dng yu cu . Thng

thng ch c mt gi tr output c a ra t hmReduce hoc khng c gi tr noc.

V d:

Gi s chng ta c mt bi ton l m s ln xut hin ca mt t trong mt

b ti liu ln, ngi dng cn phi vit mt on code tng t vi m gi sau y:

map(String key,String value)://key: tn ca ti liu

//value:ni dung ti liu

Vi mi ch ci w trong value :

EmitIntermediate(w,1);

reduce(String key,Iterator values):

//key: ch ci cn m

//values:danh sch cc s m trong map

int result = 0;

vi mi gi tr v trong values:

result += ParseInt(v);

Emit(AsString(result)) ;

Hm map thm vo mi t mt s tng ng vi s ln xut hin ca n (trong

v d n gin trn l 1). Hm reduce lm nhim v cng tt c cc s m ca t .

Sau , ngi dng cn phi thc hin thm cc th tc khai bo c t i

tng mapreduce vi tn ca cc file input, output v cc bin ty chnh. Ngi dng

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sau gi hm MapReduce, chuyn cho n i tng c t trn, lc ny cc

on code ca ngi dng c lin kt li thng qua th vin MapReduce.

Tng quan qu trnh thc thi

Qu trnh gi thc thi hmMap c phn tn trong nhiu cc my thnh vinca m my in ton bng cch t ng phn vng cc gi tr u vo thnh mt b

gm M phn. Cc phn ny c th c tnh ton song song bi cc my khc nhau.

Tng t hmReduce cng c phn tn bng cch phn vng cc kha gi tr trung

gian thnh R mnh bng cc hm phn vng (v d nh hash(key) mod R). S lng R

v hm phn vng c th c ch r bi ngi dng.

Hnh bn di cho chng ta ci nhn tng qut nht v lung thc thi mt thao tc

MapReduce.

Khi ngi dng gi hmMapReduce th cc tc v sau y s c din ra mt

cch tun t:

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Th vin MapReduce trong chng trnh ngi dng u tin s chia nh cc

file u vo thnh M mnh (thng thng kch thc mi mnh t 16-64MB,c th

iu chnh thng qua cc tham s ty chn). y, h thng in ton m my

a nguyn tc chia nh vo thc hin qu trnh tnh ton ca mnh. Vi mtchng trnh ln m tnh ton mt ln s tn rt nhiu thi gian v khng hiu qu,

tic kim thi gian thc thi chng trnh, h thng tin hnh chia chng trnh ln

thnh cc tin trnh nh thc hin tnh ton trn cc vi x l (h thng phn cng

song song to nn h thng in ton m my) tin hnh tnh ton chng trnh

song song cui cng gp li mt kt qu. Tip theo, n s to nhiu bn sao ca

chng trnh trn cm my tnh trong m my in ton. Nguyn tc sao chp cng

c a vo ng dng trong h thng in ton m my, trn mi cm my tnh

trong m my in ton thc hin mt tin trnh m chng trnh giao ph, tin trnh

ny s c to ra nhiu bn sao cho cc my tnh trong cm my tnh thc hin.

Mt trong s cc bn sao ca chng trnh s l chng trnh master. Cc

chng trnh cn li s l worker, l chng trnh s thc thi cc tc v do master giao

ph. C tt c l M tc v Map v R tc v Reduce cn c thc thi. Chng trnh

master chn cc worker rnh ri gn cho tc vMap hoc Reduce.

Worker c gn thc thi tc v Map c ni dung ca mnh gi tr u vo

tng ng, n phn tch gi tr u vo thnh cc cp kha/gi tr v chuyn chng n

cho hmMap ngi dng t nh ngha. Cc cp gi tr key/value trung gian (kt qu

ca hm Map) s c lu vo b nh m.

Sau , cc cp gi tr trong vng nh m ny s c ghi xung vng nh a

phng, v c phn thnh R vng. V tr ca cc cp kha/gi tr ny (trn b nh

a phng) s c chuyn v cho master. Chng trnh master sau s chuyn vtr ca chng cho cc worker c gn tc vReduce.

Khi mt worker thc thi tc vReduce nhn c cc v tr ca cc vng nh t

master, n dng cc li gi th tc t xa (RPC- Remote Procedure Call) c cc gi

tr ny. Sau khi worker c xong tt c cc cp gi tr trung gian ny, n s sp xp li

chng theo kha bng cch gom nhm cc cp c cng kha li vi nhau. Nu s

lng cc file trung gian ny qu ln so vi b nh th chng ta s phi cn c mt

hm sp xp ngoi

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Sau cc worker thc thi tc vReduce chuyn kha v tp cc d liu tng

ng n hm Reduce do ngi dng nh ngha, kt qu output thu c l kt qu

cui cng.

Sau khi tt c cc tc v Map vReduce u hon tt, chng trnh master gin chng trnh user program, tr v on code tip theo trong chng trnh.

Chp nhn li

Th vinMapReduce c thit k gip tnh ton trn cc lng d liu v

cng ln ca hng trm hng ngn my, do chng cn phi c c ch chp nhn li.

y l s p dng ca nguyn tc t phc v vo h thng in ton m my,

m my in ton c kh nng t phc hi li hot ng ca h thng khi xy ra mt

s li no trong cc qu trnh thc thi ca tng phn nh trong h thng tnh ton.

Li xy ra Worker

kim tra li worker,chng trnh master tin hnh ping cc my worker

sau mi mt khong thi gian nht nh, nu mt worker no khng tr li th Master

s xem nh n ang xy ra li, cc tc v map hay reduce ang thc thi worker li

s tin hnh reset li v gn cho worker khc. y c p dng nguyn tc linh ng

khc phc li h thng, chng trnh c chia nh thnh cc tiu trnh nn cc tiu

trnh ging nhau c th linh ng thc thi ti cc phn cng vi x l khc nhau v khi

mt tiu trnh b li th tiu trnh khc c th thay th thc hin nhim v ca h

thng giao ph.

i vi tc v map hon tt worker li cng phi tin hnh reset li do kt

qu trung gian c lu tr vng nh a phng v chng ta khng th truy cp n

chng. i vi tc v reduce th ngc li, ta khng cn phi reset chng v kt qu

cui cng ca tc v ny c lu trong vng nh ton cc, ta c th truy xut chngmt cch d dng.

Li xy ra Master

Nhm c th khi phc master trong trng hp xy ra li, master s tin hnh

ghi checkpoint sau khong thi gian c nh. Khi li xy ra th mt bn sao mi c th

bt u t on checkpoint lu. Nhng nu chng ta ch c 1 master th khi master

b li ton b qu trnh tnh ton MapReduce s b hy, client khi phi kim tra

trng hp ny v t khi ng li qu trnh nu mun.

Tc v backup.

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y l mt p dng ca nguyn tc d phng vo vic gii quyt bi ton trong

m my in ton, n gip cho hot ng tnh ton khng b mt khi s ra s c. Mt

trong cc nguyn nhn thng xy ra lm tng thi gian hon tt tc v MapReduce l

cc straggler. Straggler l cc my c khong thi gian hon tt mt trong s cctc v cui ca Map hoc Reduce di mt cch bt thng. Straggler c th l bt c

my no trong s cc my trong h thng m my ang c s dng. C rt nhiu

nguyn nhn to nn straggler, v d nh mt my tnh trong h thng c a cng

khng tt, khi hot ng c th gp mt s trc trc lm gim tc truy xut bnh

thng ca cng t 30Mb/s xung thnh 1Mb/s chng hn. H thng lp lch cho

cc cm my tnh lc ny phi gn tc v khc cho my l nguyn nhn lm chm tc

thc thi MapReduce (da trn s so snh tc CPU, truy xut b nh, h thng

lu tr ca my a phng, bng thng ca mng). Mt vn mi nht m Google

gp phi l mt li trong on code khi to tc v MapReduce, n lm cho cc cache

ca CPU khng th hot ng, qu trnh tnh ton ca my tnh b li do m gim

xung khong 100 ln.

Google to ra mt phng php nhm gim bt tc hi do cc straggler

gy ra. Khi cc tc v MapReduce gn hon tt, master s to ra cc tc v back up

cho cc tc v ang thc thi v gn cho cc workers rnh ri thc hin. Qu trnh

MapReduce s kt thc khi tc v nguyn thy hoc tc v back up hon tt. i vi

cc tc v MapReduce nh, phng php ny ch gip ci thin hiu nng mt vi

phn trm, nhng i vi cc tc v MapReduce ln th chng gip ci thin hiu

nng rt ng k.

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Bn trn l biu so snh tc thc thi ca chng trnh sp xp vit theo

MapReduce ca Google. Chng trnh thc hin sp xp khong 1 tetrabyte d liu.

Biu u tin l tc c cc gi tr input,biu bn di l tc thc hin sp

xp v cui cng l tc xut ra kt qu.Biu (a) th hin tc thc thi ca tc

v MapReduce hot ng bnh thng khng c cc straggler, biu (b) l khi thc

hin gp phi cc straggler trong ha trnh kt thc tc v m khng dng c ch

backup,biu (c) l khi dng c ch backup trong qu trnh thc thi MapReduce.

Chng ta nhn thy tc thc thi bnh thng vo khong 1057s, khi gp phi cc

straggler m khng c c ch backup ta s phi mt 1283s, v cui cng khi p dng

c ch backup v phi b i 200 tc v do cc straggler ny gy ra chng ta t c

tc l 933 giy ch hn 5% so vi tc thc thi bnh thng nhng li tng 44%

nu so vi tc thc thi khi gp phi cc straggler.2.4 Hadoop.

Hadoop cng ngh khai thc m vng trn Internet

(JICT) - Mong mun ca cc doanh nghi p l tn dnglng d liu khng l a ra quyt nh kinh doanh,Hadoop gip cc cng ty x l khi lng c terabyte

v thm ch l petabytes d liu phc tp tng i hiu qu vi chi ph thp hn.

Cc doanh nghip ang n lc tm kim thng tin qu gi t khi lng ln dliu phi cu trc c to ra bi cc web log, cng c clickstream, cc sn phm

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truyn thng x hi. Chnh yu t dn lm tng s quan tm n cng ngh mngun m Hadoop.

Hadoop, mt d n phn mm qun l d liu Apache vi nhn trong khungphn mm MapReduce ca Google, c thit k h tr cc ng dng s dngc s lng ln d liu cu trc v phi cu trc.

Khng ging nh cc h qun tr c s d liu truyn thng, Hadoop c thitk lm vic vi nhiu loi d liu v d liu ngun. Cng ngh HDFS ca Hadoopcho php khi lng ln cng vic c chia thnh cc khi d liu nh hn cnhn rng v phn phi trn cc phn cng ca mt cluster x l nhanh hn. Cngngh ny c s dng rng ri bi mt s trang web ln nht th gii, chng hnnh Facebook, eBay, Amazon, Baidu, v Yahoo. Cc nh quan st nhn mnh rngYahoo l mt trong nhng nh ng gp ln nht i vi Hadoop.

Cng ngh Hadoop ngy cng c s dng nhiu hn trong cc ngn hng,cng ty qung co, cc vin nghin cu, cc cng ty dc phm v cc cng ty CNTTkhc.

"Vi Hadoop bn c th ch cn mt v hai ngi l c th x l cng mt khilng d liu m mt s cng ty ln nht th gii ang x l.

Tynt, ngi s dng Hadoop, mt cng ty phn tch web, cung cp dch vphn tch cho hn 500.000 trang web. Sn phm chnh ca n l mt dch v cho phpcc nh cung cp dch v c c ci nhn su sc v vic cc dch v ca h cchia s nh th no. Mt ngy trung bnh Tynt thu thp v phn tch gn 1 terabyte dliu t hng trm triu ca cc tng tc web trn cc trang web m h quan st. Cngty chuyn sang Hadoop khong 18 thng trc, khi c s h tng d liu MySQL btu sp theo d liu m Tynt thu thp c.

Cu trc tp tin ca Hadoop cho php cc cng ty v c bn nm bt v cng ctt bt k loi tp tin d liu c cu trc v phc tp no, chng hn nh cc nht ktrn trang web, siu d liu, tp tin m thanh v video, dch v e-mail phi cu trc, dliu dng Twitter v dch v truyn thng x hi.

Do , cng ngh ny l l tng cho cc cng ty mun phn tch khi lngln d liu c cu trc v phi cu trc.

Ly d liu th t cc HDFS, tuy nhin, ch bin n khng phi l d dng haythun tin nh cc h thng c s d liu in hnh, bi v d liu khng c t chchoc cu trc, Befus ni. "V c bn nhng g Hadoop lm l a cc d liu bnngoi vo trong cc tp tin ln. N khng quan tm trong cc tp tin c g. N ch

qun l chng v m bo rng trong c nhiu bn sao ca cc tp tin."

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Ban u, ngi dng phi vit cng vic trong mt ngn ng lp trnh nh Java phn tch v sau truy vn d liu th trong Hadoop. Nhng cc cng c hin cth c s dng vit cc truy vn SQL nh d liu c lu tr trong Hadoop.

Hadoop c s dng nhiu hn cho cc ng dng kinh doanh thng minh thigian thc.

III. IN TON M MY XU HNG CNG NGH MI TI VIT NAM

D c th gii d on s l "cn sng thn cng ngh " song khi nim

in ton m my vn cn kh mi m ti Vit Nam.

IBM l doanh nghip tin phong khai trng trung tm in ton m my ti

Vit Nam vo thng 9/2008 vi khch hng u tin l l Cng ty c phn cng ngh

v truyn thng Vit Nam (VNTT). Sau , Microsoft l mt trong nhng i giatip bc in ton m my th trng Vit Nam, nhng hin vn ang trong giai

on pht trin th nghim.

Theo ng V Tn Long, Tng Gim c cng ty IBM Vit Nam: in ton

m my khng cn l xu hng m l thc t ang din ra. C th ni Vit Nam l

mt trong nhng nc u tin ASEAN a vo s dng in ton m my. T

nm 2008 n nay, ngy cng c nhiu khch hng tm n cc dch v in ton m

my ca IBM.

Tip n, in ton m my Vit Nam bt u c nhng tn hiu kh quan

khi khi FPT - nh cng ngh hng u ca Vit Nam khng nh v th tin phong

ca mnh trong cng ngh bng l k kt vi Microsoft chu -Trend Micro hp

tc pht trin "m my" chu . Nhn nh v hp tc ny, i din Trend Micro

cho rng, in ton m my s em li c hi cho Vit Nam bi cng ngh hon ton

mi s gip gii tr Vit Nam vn rt nng ng s c thm iu kin sng to v phthuy ti nng ca mnh. ng thi, vi tim nng v nhn lc, c s h tng v nht l

"tnh sn sng" ca FPT hai bn s khng ch dng li cung cp dch v v in ton

m my Vit Nam m s vn ra ton cu.

Sau cuc k kt mt tun, FPT tip tc hp tc cng "i gia" Microsoft vo

thng 05/2010. Tm im ca hp tc ny l mt tha thun nhm pht trin nn tng

in ton m my da trn cng ngh ca Microsoft. Hai bn u cng hng n

vic pht trin nn tng cho cc dch v m my bao gm truyn thng, hp tc, lutr d liu v cc dch v h tng, nhm phc v nhu cu ca ng o khch hng.

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Gn y nht, Journey to the cloud (Hnh trnh ti cng ngh in ton m

my) vi chm ngn New ways to do new things l ch hi tho do Microsoft t

chc hm 02/03/2001 va qua ti H Ni, thu ht s tham d ca hn 300 chuyn

gia IT v cc nh lnh o ca cc doanh nghip. iu ny chng t nhng vn vin ton m my hin ang thu ht s quan tm ca rt nhiu doanh nghip trong

nc, nhng ngi ang kim tm gii php nng cao nng sut cho doanh nghip.

Tuy vy, tip theo sau hi tho ngy 02/03, Vietnam Cloud computing Day

2011 (Ngy in ton m my Vit Nam 2011) din ra ngy 9/3 ti H Ni cng

a ra nhn nh: mc d in ton m my hin ang c ng dng rng ri

nhiu nc pht trin trn th gii bi li ch ng k m n em li, nhng Vit

Nam cc doanh nghip vn cha thc s mn m vi cng ngh ny. Tuy nhin theo

cc chuyn gia nhn nh, y chnh l gii php ti u cc doanh nghip nc ta

gim thiu chi ph cng nh tng hiu sut lm vic mc ti a.

V thc trng ng dng in ton m my cc doanh nghip Vit Nam, c

th rt ra kt lun nh sau: Hin nay c mt vi doanh nghip ln ti Vit Nam a

in ton m my vo ng dng v hiu sut kinh doanh c ci thin ng k. Tuy

nhin s lng l kh t. Phn ln vn ch dng mc quan tm v tm hiu.

Pht trin in ton m my ti Vit Nam cn nhiu thch thc

Khng nm ngoi xu th chung ca ngnh cng ngh thng tin th gii, Vit

Nam ang dn tip cn dch v m my thng qua cc d n ca mt s doanh

nghip nc ngoi nh Microsoft, Intel Cng ngh ny c coi l gii php cho

nhng vn m nhiu cng ty ang gp phi nh thiu nng lc cng ngh thng tin,

chi ph u t hn ch Hu ht cc nh lnh o cng ngh thng tin u kh k

vng khi nhn nh v cng ngh ny.

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ng Dng Dng Triu, Gim c iu hnh FIS chia s: Chng ti nhn ra

nhiu li ch khi ng hp tc xy dng trung tm d liu s dng cng ngh in

ton m my ca Microsoft. Hai bn chia s tm nhn v tng lai ca ngnh tin hc

-ni m cc dch v in ton m my s tr nn ph bin v c s dng rng ri

Vit Nam vo nm 2015- v chng ti c mc tiu tr thnh nhng ngi dn u

trong lnh vc mi m ny.

Theo ng Nguyn Huy Cng, CEO ca Tinh Vn Consulting, hin nay nhiu

cng ty ang hoang ph ti nguyn nh khng khai thc ht cng sut ca h thng

my ch, u t qu nhiu v mt con ngi. Trong khi , v l thuyt, cloud

computing s cho php doanh nghip khng cn tp trung qu nhiu cho c s h tnghoc nng cp ng dng, khng i hi ngun nhn lc ln v c th d dng thay i

quy m khi cn.

ng Hong L Minh, Vin trng Vin cng nghip phn mm v ni dung s

Vit Nam (NISCI), khng nh in ton m my l mc tiu m th gii cng nh

ngnh cng ngh thng tin trong nc hng ti v y chnh l nhn t thc y cc

qu trnh chuyn i kinh doanh.

Tuy nhin, theo cc chuyn gia ca Intel nhn nh th in ton m my chc

chn khng phi dnh cho tt c mi ngi v cho mi nhu cu. Mc d li ch ca

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in ton m my l khng th ph nhn, nhng cc doanh nghip cn cn nhc n

cc yu t khc nhau khi tnh n chuyn ng dng in ton m my, c th nh:

ro cn k thut, an ton thng tin, ngun vn hin i quy trnh kinh doanh bng

vic ng dng cng ngh thng tin, gim chi tiu cho phn cng, phn mm, an tonbng thu ngoi phn mm c s h tng, tnh linh hot v kh nng m rng ca

ngun lc cng ngh thng tin trc khi quyt nh ng dng in ton m my vo

sn xut kinh doanh. Vit Nam cng khng phi l mt ngoi l.

Bn l hi ngh Ngy in ton m my Vit Nam 2011, ng Phan Thanh

Sn, Gim c cng ngh ca cng ty Cisco, chia s cn nhiu kh khn trong vic

trin khai in ton m my ti Vit Nam. Theo ng, vn chnh sch, ng

truyn bng thng v nhn thc ca doanh nghip l nhng thch thc ln nht vi

cng ngh mi ny.

ng thi, mt s doanh nghip cho bit h v ang s dng cc dch v

m my min ph nh Google Apps, nhng vn cn thi gian tm hiu nhiu hn

nhng li ch cng nh ri ro v tnh an ton d liu. ng Nguyn Thin Tm, Gim

c khch hng ca Cng ty Sutrix Media Vit Nam, cho bit nu s dng cc dch v

in ton m my th i hi mi nhn vin phi c k nng nht nh v cng ngh

thng tin. Hin cng ty c s dng Google Docs, nhng ch dng mc trao i,

chia s ti liu.

Khng ch c vy, ng L c Quyt, Ph gim c Cng ty c phn Th gii

vn ti, cho bit ng vn cn e ngi khi a nhng thng tin lin quan n ti chnh

ca cng ty ln dch v in ton m my v khng bit c d liu ca mnh u

trn mng. ng Quyt cng ni m hnh ng dng in ton m my ph thuc

nhiu vo Internet m cha chc lc no cng c th truy cp vo Internet.Tm li, ngi vit mn li ca ng Hong L Minh - Vin trng Vin Cng

nghip phn mm v Ni dung s Vit Nam - kt thc bi vit ny: "Bn cht ca

in ton m my l s hi t cc thnh tu v nghin cu pht trin cc cng ngh

mi; cc quan im v ng dng CNTT hin nay trn th gii cng nh Vit Nam.

in ton m my cng l mt trong nhng khi nim m h nht t trc n nay

chng ta gp phi. N cng ging nh ci g trn cao, trong my, chng ta khng

th nhn bit c. Nhng cng chnh l mc tiu m hin nay ngnh CNTT truyn

thng ang hng ti".

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C th ni in ton m my ang to c hi cho cc doanh nghip hot ng

hiu qu, thng minh v tit kim chi ph hn. Cc doanh nghip Vit Nam ang c

iu kin thun li s dng nhng tin ch ny. Vn l bn lnh ca doanh

nghip c dm ng dng cng ngh mi vo qun l iu hnh sn xut kinh doanhhay khng m thi. V vy, d cng ty quy m ln hay nh, bn cng nn th dng

dch v ny, nu khng c th bn b l mt c hi kinh doanh trong tng lai.

IV. IN TON M MY CA MICROSOFT.

in ton m my: Xu hng chuyn i chnh ca Microsoft

in ton m my l trng tm pht trin ca Microsoft

Trc s cnh tranh mnh m ca cc i th cng ngh ln, Microsoft ang

to ra nhng chuyn bin mnh m v c tnh t ph, cung cp nhng sn phm a

dng v p ng tt hn na nhu cu ca th trng. in ton m my chnh p n

tt nht nhm gii quyt bi ton cnh tranh, tng cng sc mnh ca Microsoft, p

ng hn na nhu cu ca ngi dng,

R rng, c s pht trin trong chin lc pht trin cng ngh ca Microsoft.

Bn cnh cc sn phm phn mm truyn thng (Office)phn cng (cc HH

Windows 7, Windows 8..) lc ny Microsoft ang pht trin cc hnh thc cung cp v

cho thu cc dch v c ng dng ca in ton m my cho doanh nghip v ngi

dng. y s l m hnh pht trin, chuyn i chnh ca Microsoft trong tng lai.

Cng ngh in ton m my ca Microsoft

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Microsoft u t pht trin mnh m cc ng dng in ton m my

Microsoft pht trin cc ng dng, nn tng v cc lp c s h tng ca

cng ngh in ton theo tng lp c xy dng trong cc trung tm d liu khchhng, trung tm d liu Microsoft hoc trung tm cung cp dch v d liu (STB).

Sc mnh v tim nng ca in ton m my th hin qua nhng s liu c th:

- Office 365 phin bn beta thu ht hng trm ngi s dng, phin bn chnh

thc ca Office 365 t thnh cng ngoi mong i. Theo thng k, c 25 giy th c

thm 1 ti khon Office 365 mi.

- 10 ngn khch hng ang s dng nn tng Windows Azure.

- S lng ngy cng tng cc i tc pht trin ng dng thc t v cung cp

cc gii php in ton m my

- S lng cc i tc trn ton th gii s dng cc tin ch m my (Cloud

Essentials) v Accelerate tng 500% k t thng 7 nm 2010, s lng s dng tin

ch tng gp 23 ln, s lng i tc s dng dch v Office 365 tng gp 6 ln.

- S lng cc i tc thu dch v trc tuyn t Microsoft tng 250%.

- S lng khch hng in ton c nhn s dng dch v h iu hnh o ha

Hyper-V tng gp i trong 12 thng (k t WPC10).

- Theo thng k cha chnh thc, 57% i tc tham d WPC 2011 tuyn b s

pht trin cng ngh in ton m my.

Hin Microsoft c hn 640.000 i tc a phng trn khp th gii vi hn

15 triu nhn vin c trnh cao v to ra doanh thu a phng ln ti 537 t USD

(IDC 2009). Hng cng ang tng tc u t mnh m vo cc gii php in ton

m my, c s h tng nhm p ng cc nhu cu khc nhau ca ngi dng, doanhnghip. C th:

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- Tnh n cui nm 2011, c khong 90% trong tng s 40000 k s ca

Microsoft s nghin cc cc ng dng v dch v mi ca in ton m my.

- 55 t USD u t cho cc ng dng in ton m my vi mc ch pht

trin cng ng vo nm 2014. (Theo IDC, thng 06/2011)- 30% cc nh qun l trung tm d liu ln k hoch u t vo ng dng

in ton c nhn trong nm 2011 (theo Gartner)

- Chi ph u t cho ng dng cng ngh in ton m my s tng t 70 t

ln 136 t USD, chim khong 12% tng vn ngn sch u t cho lnh vc cng ngh

thng tin. (Ngin cu AMI, thng 05/2011)

Dch v in ton m my ca Microsoft phc v li ch khch hng

Cc dch v in ton m my ca Microsoft u hng n khch hng

Nhng dch v in ton m my do Microsoft ang cung cp hin nay rt a

dng, nhm p ng ti u hiu qu cng vic ca khch hng, gim chi ph sn xut,gip doanh nghip v c nhng c nhn c th tn dng ti a cc ti nguyn ng

dng:

- Cc dch v in ton m my dnh cho doanh nghip:

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Dch v in ton m my dnh cho cc doanh nghip

Dch v pht trin C s h tng Windows Server Hyper V: Cng ngh o ha

server th h mi ca Microsoft v l thnh phn quan trng trong h iu hnh

Windows Server 2008. Kin trc m ca Hyper-V cho php cc nhm pht trin ni

b v cc nh pht trin phn mm ca hng th ba ci tin cng ngh ny v cc cng

c. Vi Hyper-V, Microsoft cung cp mt nn tng o ha mnh v linh hot, c th

p ng nhu cu o ha mi cp cho mi trng doanh nghip.

Dch v nn tng Windows Azure: Window Azure l h iu hnh ca

Microsoft cho in ton m my, gip cc ng dng c kh nng tng gim bin

ty thuc vo yu cu ca doanh nghip. Gip cc chuyn gia phn mm ch cn sng

to trn nn tng sn sng h tr ngn ng ca h - .Net, PHP, Java hoc Ruby. Thm

vo , vi m hnh kinh doanh tr ph s dng, s khng phi tn chi ph cho

nhng dch v tng l cn thit nhng li khng bao gi s dng. iu ny mang li

li ch cho c hai bn.Cc dch v Phn mm:

Microsoft Office 365: c thit k lm vic vi cc phn mm, thit b, in

thoi, v cc trnh duyt sn c ti doanh nghip. iu ny gip nhn vin sc mnh

truy cp thng tin v gi nng sut trn tt c cc phng tin truy cp trong khi

vn m bo an ninh v vn gi c cc ng dng c.

Microsoft Dynamics CRM online: B gii php qun l doanh nghip h tr

vic qun l ti chnh, mi quan h khch hng v chui cung ng, thc y vic s

dng tng cng hiu sut, hp l ha cc quy trnh vn hnh nghip v t hiu

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qu tt hn, nng cao mc chc chn trong vic a ra cc quyt nh ng lc v

to ra nhiu n hng hn trong khi vn m bo mc bo mt thng tin tt nht.

- Cc dch v in ton m my dnh cho khch hng c nhn

Dch v in ton m my dnh cho khch hng c nhn

XBOX LIVE: h thng dch v online dnh cho vic chi game v cc ni dung

c phn phi vi Microsoft i vi h thng my xbox v xbox 360 .

Bing: Cng c tm kim do Microsoft cung cp cc kt qu tm kim tng hp

da trn nhng thut ng tm kim. Bing c nhiu ng dng nh tm kim hnh nh,

video, ti liu

Windows Live ID: dch v "ng nhp thng nht" c pht trin v cung cp

bi Microsoft cho php ngi dng ng nhp vo nhiu trang web m ch s dng

mt ti khon duy nht. Trc n c t v tr l dch v ng k n cho tt c

cc trang web thng mi.Windows Live Hotmail: Windows Live Hotmail l dch v lu tr, gi v nhn

mail. nm trong dng dch v Windows Live ca tp on Microsoft. S dng

Windows Live Hotmail, ngi dng c sn 5GB dung lng mail min ph, kh

nng qun l nhiu a ch mail cng lc, kh nng ty bin cao nh thay i giao din

theo phong cch, mu sc yu thch ca bn.

Windows Update: Windows Update l mt Web site tng tc cho php ngi

dng thng xuyn c c p nht cc bn sa li v bo mt, hiu nng v ci thin

tnh nng ph hp vi my tnh chy Windows.

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V.TNG KT.

in ton m my sn sng l mt bn quan trng trong ngnh cng nghip

cng ngh by gi v trong tng lai gn. Gn y n cung cp cc phng tin chocng ngh thng tin c phn pht cho ngi tiu dng nh l mt dch v. S lng

cc sn phm v cc ngh dch v trong khng gian in ton m my tip tc pht

trin v nhn mnh mt thc t l n l ni m mi th ang hng ti.

DANH SCH NHM 9

1. Dng Vn Tho

2. Nguyn Th Thng

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31/31

3. Nguyn ng Ton

4. Trn Minh Th

tim hieu ve dien toan dam may doc

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