1
GATE CSE 1995
Subjective
+5
-0
A computer installation has 1000K of main memory. The jobs arrive and finish in the following sequence.
Job 1 requiring 200k arrives
Job 2 requiring 350k arrives
Job 3 requiring 300k arrives
Job 1 finishes
Job 4 requiring 120k arrives
Job 5 requiring 150k arrives
Job 6 requiring 80k arrives

(a) Draw the memory allocation table using Best Fit and First fit algorithm.
(b) Which algorithm performs better for this sequence?

2
GATE CSE 1995
Subjective
+2
-0
If the disk in (a) is rotating at $$3600$$ rpm, determine the effective data transfer rate which is defined as the number of bytes transferred per second between disk and memory.
3
GATE CSE 1995
Subjective
+5
-0
If the overhead for formatting a disk is $$96$$ bytes for $$40000$$ bytes sector, Compute the unformatted capacity of the disk of the following parameters:
Number of surface: $$8$$
Outer diameter of the disk : $$12cm$$
Inner diameter of the disk: $$4cm$$
Inter track space: $$0.1mm$$
Number of sectors per track: $$20$$
4
GATE CSE 1995
Subjective
+5
-0
The head of a moving head disk with $$100$$ tracks numbered $$0$$ to $$99$$ is currently serving a request at tract $$55.$$ If the queue of requests kept in $$FIFO$$ order is $$10, 70, 75, 23, 65$$ Which of the two disk scheduling algorithms $$FCFS$$ (First Come First Served) and $$SSTF$$ (Shortest Seek Time First) will require less head movement? Find the head movement for each of the algorithms.