Consider three CPU-intensive processes, which require 10, 20 and 30 time units and arrive at times 0, 2 and 6, respectively. How many context switches are needed, if the operating system implements a shortest remaining time first scheduling algorithm? Do not count the context switches at time zero and at the end.

Consider three CPU-intensive processes, which require 10, 20 and 30 ti

1.	Consider three CPU-intensive processes, which require 10, 20 and 30 time units and arrive at times 0, 2 and 6, respectively. How many context switches are needed, if the operating system implements a shortest remaining time first scheduling algorithm? Do not count the context switches at time zero and at the end.
A.	1
B.	2
C.	3
D.	4
Answer» C. 3

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