Chương 6 Thuật toán loại trừ tương hỗ và bầu cử potx

NỘI DUNG
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Giới thiệu
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Loại trừ tương hỗ không dựa trên Token
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Loại trừ tương hỗ dựa trên Token
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Thuật toán bầu cử
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Kết luận
DUYTAN
UNIVERSITY
GIỚI THIỆU
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           
 !
"#$%
"#%&'()()*+(,(-
)./0#%123"#2!
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45-)6$loại trừ lẫn nhau7
,(-)0859$%5:;
DUYTAN
UNIVERSITY
Đồng bộ hóa tiến trình <3&&2(=%!
> Loại trừ tương hỗ ? 1 ,  truy
cập đồng thời@%.A
tài nguyên B dữ liệu được chia sẻ+
3loại trừ lẫn nhau;

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CDE
%&'7&FGH7
18I1J%;
DUYTAN
UNIVERSITY
Loại trừ tương hỗ K%1LM1&!
GIỚI THIỆU
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N.A()6,O1PQ(@
.A%)@%/.AR
 *  7   %  (  . 
()loại trừ tương hỗ.đồng bộ hóa
11),%&,(.
()(MS(%R&QGT1
MF1P%G:!
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C6$   E   % 6 MD( G
O.()U13+7
:F%&V+:8.+;;;!
DUYTAN
UNIVERSITY
GIỚI THIỆU
Loại trừ tương hỗ K%1LM1&!
> N7 MF 1P -   6$ &F GH - ./
0
"W()*XB1+*
) . ./0718I1J% .O
OYE,&Z&FGH5[GT
16%&'/1[

>8I6R\E,%?
"W7%.1* 
"23%3&
"K3&&%3&
"#G.%%13&
DUYTAN
UNIVERSITY
Loại trừ tương hỗ đối với hệ thống tập trung
GIỚI THIỆU
>C18I6R\O.A&
]E.BE
6AE 8@%
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^%RO718I1J%
D?
_;<6RG%)C3
`;<6REG%)C3
a;<6RG%)b
Loại trừ tương hỗ đối với hệ thống phân tán
Phương pháp tiếp cận dựa trên Token
>K'3!G(56%&'T%
&3
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K&36.#2@%&Q
T3;
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8I1J%6OOQ.3
1G(5;
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#)7?C3c+c%"

d%e%1%23G
DUYTAN
UNIVERSITY
> 2F GH % B - .f 1)   E
6%VT%&37M:&3
&Z.#23;
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 #   ) 7? #3%1 #G%+
c%"d%e%1%
Phương pháp tiếp cận không dựa trên Token
DUYTAN
UNIVERSITY
Phương pháp tiếp cận dựa trên Quorum
>K\&3()*&7#2I
@%&36X1&87
*!;
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g%b59 %&3;
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#&3(:7OOY
h()*6Q5 1[;
DUYTAN
UNIVERSITY
Thuật toán Central Coordinator
>
K6 *X1-.)
G%!
>
N- .)D5,(-7.
#2

"N7#2+Fi()*
.A- .).&%$O1$
$ % $  ,   7  H .A 
E.!;
"CO1$I-.),(-.#2;
"2%E.#2+
E-.)
DUYTAN
UNIVERSITY
Thuật toán Central Coordinator
DUYTAN
UNIVERSITY
>
6(1RO.G];
>
#16(fjh%i\1*()
*&FGH)#2;
Vấn đề xãy ra ?
"N-.)7Q,OiV%
"N-.)kl58@%%1?
mn-.):3+-.)A
O68
mN-.)71T
8 % 7 ( +    * F S 6
8(7X.h-.)A
6X;
Thuật toán Central Coordinator
DUYTAN
UNIVERSITY
Thuật toán Ricart-Agrawala

•
C E 6$ D +   ( &F
GH1%&.1E&FGH
-.)D!;
>
oO:)(-E3
,(ipqpr;
>
 2F GH % 18 E ? cLbsL2C .
cL<t
DUYTAN
UNIVERSITY
>
C()*0.#2O?
"28E %?
mqG3U3%3qu+3&&qu!
mC)()
mnSvG5$%%G5$%
*%!
"oQE()*5O 
8%.A/()
"n6.#25O
SO1$i(
"C(.0+&FGH()
Thuật toán Ricart-Agrawala
DUYTAN
UNIVERSITY
>
W()*?
"nkhông quan tâm?QrW

Q
"n%Q#2?WEO1$.add
()*.
"n.I%vQE?
m2&S$%2A5&Zi
mn%?QOK
mni+EO1$.add
.
•
WM)#2
"oQrW5O)
Thuật toán Ricart-Agrawala
DUYTAN
UNIVERSITY
Thuật toán Ricart-Agrawala
DUYTAN
UNIVERSITY
>
Vấn đề xãy ra:
  " C  1    16 16 (  
i+fj`"_!i.#2?"_!
()*."_!O1$;
"258@%59%%0B
8EH
B6;
Thuật toán Ricart-Agrawala
DUYTAN
UNIVERSITY
Thuật toán Lamport
•

K\G(()*
"#()*18I1J%
•
Yêu cầu critical section?
"C<
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Qrequest(i, T
i
)5G3
"t)*.:w))@%
"W_<
x
()*+O 
S$%ack
Lamport time
DUYTAN
UNIVERSITY
Đăng nhập vào CS:
"<6iackB release!I\
.AG5$%1ARC
"t)*@%<G5$%&A5
@%
"2.Ac%"d%e%1%?
mKX- Q18
mC,(:G%)M3()*@%1
&A5@%
Thuật toán Lamport
DUYTAN
UNIVERSITY
Releasing critical section?

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"oQ_S$%Erelease
"W6Erelease
+ 8j()*I@%
N-(7D(%G5$%&A
57(.#2

Thuật toán Lamport
DUYTAN
UNIVERSITY
Thuật toán Token Ring
•
NRO57O,(18I1J%?
&iM<_+<`+;;;;<.f1
•
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:%h@%11-@%
36A-
•
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token(R)
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DUYTAN
UNIVERSITY
•
Thuật toán
"C36Q8_;
"C36(-I_1
-@%,%.ff
"W_()*0.#2+&Z
_3I1-
)@%.&%T18+&% 15(
3.
"#2+&%$j#2+O183
M@%36-

"W,636E()*
.#2+%(1 (73GX.f
f;
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DUYTAN
UNIVERSITY
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n75I_"_i763;
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E()*3;
C(88O
B+M&5%6

3  . #2; n 8    
6$Oy;
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I.f;
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n,iT3EE+
G(576X+&Z8183..6,%GX
3.ff
Thuật toán Token Ring
DUYTAN
UNIVERSITY
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z7
"NOO18I6R\
"{:6 @%
"g6k"2%.%l()MS(%
&,1A
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#.5-MS(%
"n:5',!O
0R.8i
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WEOO3pqpr
"{S(%?E
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