VirtualīMemoryīManagement
KlaraīNahrstedt/SamīKing
October 5, 2007
October
ī
5,
ī
2007
Prepare for your exams
Study with the several resources on Docsity
Earn points to download
Earn points by helping other students or get them with a premium plan
Guidelines and tips
Prepare for your exams
Study with the several resources on Docsity
Earn points to download
Earn points by helping other students or get them with a premium plan
Virtual Memory Management: Midterm Preparation Material, Assignments of Operating Systems
Information about the virtual memory management midterm for cs 423g operating systems course. It includes topics covered, exam format, and important dates. Students are expected to understand concepts related to mono-programming, multiprogramming, swapping, paging, page replacement algorithms, and memory management strategies.
Typology: Assignments
Pre 2010
1 / 40
This page cannot be seen from the preview
Don't miss anything!
Related documents
Partial preview of the text
Download Virtual Memory Management: Midterm Preparation Material and more Assignments Operating Systems in PDF only on Docsity!
Virtual
Memory
Management
Klara^ Nahrstedt/Sam
King
October 5, 2007October
5,^2007
AdministrativeAdministrative
ā¢^ Midterm
ā^ October
8,^ Monday,
10 ā10:50am
,^
y,
-^1304 SC
- onācampus
students
-^3405 SC
- local^ Internet
students
T^ iā¢ Topics^ ā^ see^ newsgroup
for^ reading
list
-^ no VMM and memory management on midtermno^ VMM
and^ memory
management
on^ midterm
ā¢^ HW
ā deadline
October
5,^ Friday,
midnight
-^ Submission
on^ compass,
-^ Submission
format^
pdf or^ doc
-^ Length
- as^ much
as^ you^ need
to^ explain
the^ problems
Memory
Management (
) (Review)
-^ Basic^ Memory
Management
-^ Monoāprogramming
without^ Swapping
or^ Paging
-^ Multiprogramming
with^ Fixed
Partitions
-^ Swapping
blā Variable^ Partitions
-^ Virtual
Memory^
Management
-^ PagingP^ T blā^ Page^ Table ā^ Multiālevel
Page^ Tables
-^ TLB^ ā Translation
Lookaside Buffers
-^ Page Replacement Algorithmsā^ Page^ Replacement
Algorithms
-^ Optimal ā¢^ FIFO ā¢^ Second^ ChanceLRUā¢^ LRU ā¢^ Clock^ Page
Replacement
-^ Working^ Set
Basic^ Memory
Management
Monoprogramming
without^
Swapping
or^ Paging
Three simple ways of organizing memory Three^ simple
ways^ of
organizing
memory
ā^ an^ operating
system
with^ one
user^ process
Multiprogramming
with^
Fixed Partitions
-^ Fixed^ memory
partitions
-^ separate
input^ queues
for^ each^ partition
-^ single input queue single^ input
queue
Modeling
Multiprogramming^ Degree^ of^ multiprogramming
CPU^ utilization
as^ a^ function
of^ number
of^ processes
in^ memory
Relocation RegisterRelocation
Register Base RegisterBase RegisterBA
Memory
CPUInstruction^
MA
PhysicalAddress LogicalAddress^
Memory
InstructionAddress
MA^
MA+BA
ProtectionProtection
ā¢^ Problem:Problem:^ ā^ How
to^ prevent
a^ malicious
process
to^ write
or
jump into other user
's or OS partitions?
jump^ into
other^ user s
or^ OS^ partitions?
SwappingSwapping
ā¢^ What is swapping?What
is^ swapping?
ā¢^ Why
was^ swapping
introduced?
10/3/^
CS^ 423g^ ā^ Operating
Systems,^ Klara Nahrstedt^
Variable
Partitions
and^ Fragmentation
Monitor^
Job 1^
Job 2^
Job 3^
Job 4^
Free
1 Monitor
Job 1^
Job 3^
Job 4^
Free
2 Monitor
Job 1^
Job 3^
Job 4^
Free
2 Monitor
Job 1^
Job 3^
Job 4^
Free
Job 5 3 Monitor
Job 3^
Job 4^
Free
Job 5^
Job 6
4 Monitor
Job 3^
Free
Job 5^
Job 6
Job 7^
Job 8
55^ Memory
wasted^ by
External
Fragmentation
10/3/^
CS^ 423g^ ā^ Operating
Systems,^ Klara Nahrstedt^
Storage Placement StrategiesStorage
Placement
Strategies
ā¢^ Analogy:Analogy:^ ā Shoe
FittingValet parking
ā Valet
parking
ā¢^ Best
Fit Fi t Fit
ā¢^ First
Fit
ā¢^ Next
Fit.
ā¢^ Worst
Fit.
Virtual
Memory
Virtual
Memory
h^
d f^
f h
The^ position
and^ function
of^ the
MMU
Paging
Request
1 Page Table
Real Memory
Request Page 3
3 1 2 Memory^
1 2 Page TableVM Frame^234 1 2
3 4
3 4
Virtual Memory Stored on Disk
Disk
1 2
3 4
5 6
7 8
Paging
1 Page Table
Real Memory
Request Page 1
3 1 1 2 Memory^
1 2 Page TableVM Frame^1 1 2
3 4
3 4
1 2 Virtual Memory Stored on Disk
3 4
Disk
1 2
3 4
5 6
7 8