!
!"
#
$
%
&$
'(
''(
'''(
) (*
+ ,
)-( .
+ ,
) ("
+ ,
+ /
-
0
!
$
$
-
332 )
+
$
)
(
12
(!
visit us at www.operatingsystemassignmenthelp.com or email us at - [email protected] or
call us at - +1 520 8371215
!
" #
0
- $
- $
!
-
!0
-
$$
+*
% $
.
% $
$
$
% $
$ -
.
(
-( 4
5
(5
( 54
*
) (
.
1
$ -
8
6
9
.6
6 '/0)
: ;
$
5.7
)
7
!
5( 6 !
5 6 45 5
(
Assume you have a page reference string for a process with m frames (initially all empty). The
page reference string has length p with n distinct page numbers occurring in it.For
it.For any pagepage
replacement algorithms,
a. What is a lower bound on the number of page faults?
visit us at www.operatingsystemassignmenthelp.com or email us at - [email protected] or
call us at - +1 520 8371215
b. What is an upper bound on the number of page faults? Give necessary conditions to hold for
both cases.
Answer:a. The lower bound is equal to the number of distinct pages n – one page fault per each page.
Necessary condition: m n
b. The upper bound is equal to the length of the reference string p . The necessary condition is
that every referenced page is not in the memory at the moment of the reference.
Question:Using the page reference sequence 1, 2, 3,4, 1, 2, 5, 1, 2, 3, 4, 5 determine the number of page
faults which will occur for FIFO, Optimal, and LRU page replacement algorithms. Assume that
three page frames are available and that they are initially empty Show why certain pages are
swapped-out when new pages are swapped-in.
Answer:-
FIFO
visit us at www.operatingsystemassignmenthelp.com or email us at - [email protected] or
call us at - +1 520 8371215
Optimal
$
visit us at www.operatingsystemassignmenthelp.com or email us at - [email protected] or
call us at - +1 520 8371215
9
$
$
-
!0
<
)
#
("
/<2
,
-( "
*'*8
,
("
=<2
#(
,
("
,
( /<2
:
-( *'*8
:
( =<2
:
(0
>
#
-
-
#
>
#
-$
(
3-
# 5 >
-
)
?
!
visit us at www.operatingsystemassignmenthelp.com or email us at - [email protected] or
call us at - +1 520 8371215