Question: Assume a uniprocessor system has three processes (P1, P2, and P3) and P1 needs four
(4), P2 needs six (6), and P3 needs three (3) seconds CPU time. Each of which needs
five (5), two (2), three (3) seconds of input waiting time respectively and three (3),
four (4), three (3) seconds of output waiting time respectively. How long will it take
to complete the processes in:
a. Batch processing system
b. Multiprogramming processing system
Also, calculate the time efficiency.
https://www.youtube.com/watch?v=VOujubrovpE&list=PLlqmJM8g9yirpfgriSa1UAcsMXBHBi69Z
Solution:
A)
Here,
C = Completion
I = Input
O = Output
Batch Processing
Completion is 33s
We know,
Efficacy formula : (Total CPU Time) / Completion Time
Efficacy = (4+6+3) / 33
= 39.3%
B)
Here,
C = Completion
I = Input
O = Output
Multiprogramming Processing System
Completion is (5+4+6+6)= 21s
We know,
Efficacy formula : (Total CPU Time) / Completion Time
Efficacy = (4+6+3) / 21
= 61.4%
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