Friday 25 January 2013
Question 1: [Marks 15]
Let us consider that there is a logical address 1027 and a page table given below for process A. Let us consider
that logical address space is of 16-bit with a 2Kilobyte page size and physical address space is also of 16-bit.
a) Calculate value of p [Marks 4]
b) Calculate value of d [Marks 3]
c) Write down the physical address in both binary and decimal form to which logical address 1027 will be
mapped. Also mention the intermediate steps. If you will not write down the intermediate steps and if you
will just write only the physical address then you will get zero marks. [Marks 8]
Page Table:
P F
0 9
1 7
2 3
Question 2 [Marks 5]
Let us consider that a resource type R has 19 units and there are 5 processes A, B, C, D and E in the system. Let
us consider that process A has 4, B has 3, C has 4, D has 1 and E has 3 instances of resource type R. Suppose that
process A requires 3, B requires 6, C requires 4, D requires 1 and E requires 3 more instances of resource type R.
Now let us suppose that at time instance T1, Process B requests 3 instances of resource type R and those 3
instances has been granted to process B. Does there exist any safe sequence in this situation? If yes then write
down the safe sequence and if not then give reason/justification to support your answer?
Let us consider that there is a logical address 1027 and a page table given below for process A. Let us consider
that logical address space is of 16-bit with a 2Kilobyte page size and physical address space is also of 16-bit.
a) Calculate value of p [Marks 4]
b) Calculate value of d [Marks 3]
c) Write down the physical address in both binary and decimal form to which logical address 1027 will be
mapped. Also mention the intermediate steps. If you will not write down the intermediate steps and if you
will just write only the physical address then you will get zero marks. [Marks 8]
Page Table:
P F
0 9
1 7
2 3
Question 2 [Marks 5]
Let us consider that a resource type R has 19 units and there are 5 processes A, B, C, D and E in the system. Let
us consider that process A has 4, B has 3, C has 4, D has 1 and E has 3 instances of resource type R. Suppose that
process A requires 3, B requires 6, C requires 4, D requires 1 and E requires 3 more instances of resource type R.
Now let us suppose that at time instance T1, Process B requests 3 instances of resource type R and those 3
instances has been granted to process B. Does there exist any safe sequence in this situation? If yes then write
down the safe sequence and if not then give reason/justification to support your answer?
