Persistent Technical Question Paper

Persistence paper SGSITS

If there r n proceses and each process waits p time in waiting state then cpu utilization is-:
a) n(1-p)
b) n*p

A string of pages were given and no of page faults have to be found in LRU algorithm 
here is a file server which provides locking for mutual exclusion . if any procees locks the file and abruptly terminated this will result in indefinitely locking .The solution they found is to implement a timer for locking of file i.e. if time outs then server assumes that file is indefinitely locked and terminate the process –
a) this solution is perfect for mutual exclusion
b) this will solve indefinite locking
c) this will result in interleaving of file between processes

A critical section is –
ans a set of instruction which is shared by many processes
There was a question on automata ans – the resultant string will have even no of c
CFG was given 
S -> 1 S 1
S-> 0 S 0
S -> 1 1
S -> 0 0
Find out the string

One singly circular ordered list is there if M elements are ti be inserted what will be the complexity of time
a) O(M*N) 
b) O(M*(M+N))
c) O ((M+N) * log(M+N))

find postfix and prefix of 
A + B * ( C + D ) / E + F 

Find out shortest path from A to B 
A B C D E
A 0 m
B m 0 2 2 m
C 0 5
D 0 6
E 0

From the following when 43 will not be found by binary search (a series was given with last element 43 in each)
From 100 – 999 find the prob. Of getting 3 digit no with no 7 in any of its digit
a) 18/25
b) 10/25
c) 729/1000

from the set {a,b,c,d,e,f}find no of arrangements for 3 alphabet with no data repeated
To save space which option is better 
a) write all join operation than select than project
b) ---------,,------------------than project----select
c) ----------,,-----------------in b/w select and project
Employee = { e_no , salary, fname, lname}
Works_On = {e_no, p_no, hrs}
Project = {p_no, p_name}
select e_no from Employee where salary = salary
a) query invalid

Select fname ,lname from Employee where e_no in (select e_no from works_on where p_no =(select * from project))
a) name of Employee who works on all project

B tree is different from other 
a) has fixed index file size
b) is better for queries like < <= > >= 
c) searching will be easy

func(char *s1,char * s2)
{
char *t;
t=s1;
s1=s2;
s2=t;
}
void main()
{
char *s1=”jack”, *s2=”jill”;
func(s1,s2);
printf(“%s %s ”,s1,s2);
}
OUTPUT jack jill
void main()
{
int a[5] ={1,2,3,4,5},i,j=2;
for (i =0;i<5;i++ )
func(j,a[i]);
for (i =0;i<5;i++ )
printf(“%d”,a[i]);
}
func(int j,int *a)
{
j=j+1;
a=a+j;
}
oid main()
{
for (a=1;a<=100;a++)
for(b=a;b<=100;b++)
foo();
} 
foo()
{ }
how many times foo will be called. 
a) 5050
b) 1010

A hash table has a sie of 11 and data filled in its position like{3,5,7,9,6}how many comparisons have to be made if data is not found in the list in worst case
a) 2
b) 6
c) 11

packet switching is better than circuit switching coz
a) it takes less time
b) it takes less bandwidth

Addition of two sparse matrix in 3 tuple notation ---time 30 min
24a tree has 1000000 nodes than how many search r required to search a node 
a) 25

A prgrm to arrange a string in order of occurrence of the character