Question

Let T1 transfer $500 from A to B, and T2 transfer 30% of the balance from A to B. Taking this scenario as example, explain the following
a. Serial Schedule ( T1 followed by T2)
b. Serial Schedule ( T2 followed by T1)
C. List out the advantages and limitations of serial scheduling in transaction processing

Answer 1

As per the given question,

$T_1$ transfers $500 from A to B and $T_2$ transfers 30% of the balance from A to B

a) $T_1$ followed by $T_2$

Transaction $T_1$

read(A)

A:=A-500

write (A)

read(B)

B:=B+500

write(B)

Transaction $T_2$

read(A)

temp:=A*0.3

A:=A-temp

write(A)

read(B)

B:=B+temp

write(B)

b) Serial schedule $T_2$ followed by $T_1$

Transaction ($T_1$)

read(A)

A:=A-500

write(A)

Transaction $(T_2)$ :

read(A)

temp:=A*0.3

A:=A-temp

write(A)

Transaction ($T_1$)

read(B)

B:=B+500

write(B)

Transaction $(T_2)$ :

read(B)

B:=B+temp

write(B)

c) The main advantages of serial scheduling, it gives the guarantee for data consistency.

It have the high average waiting time, low response time and low throughput could be possible.