Chapter 8: Memory Management

More documents

Recommendations

Info

Contiguous Allocation (Cont.)!Multiple-partition allocation" Hole – block of available memory; holes of various size arescattered throughout memory" When a process arrives, it is allocated memory from a holelarge enough to accommodate it" Operating system maintains information about:a) allocated partitions b) free partitions (hole)"OS"OS"OS"OS"process 5"process 5"process 5"process 5"process 9"process 9"process 8"process 10"process 2"process 2"process 2"process 2"Operating System Concepts!8.22! Silberschatz, Galvin and Gagne ©2005!
Dynamic Storage-Allocation Problem!How to satisfy a request of size n from a list of free holes"First-fit: Allocate the first hole that is big enough"Best-fit: Allocate the smallest hole that is big enough;must search entire list, unless ordered by size. Producesthe smallest leftover hole."Worst-fit: Allocate the largest hole; must also searchentire list. Produces the largest leftover hole."First-fit and best-fit better than worst-fit in terms ofspeed and storage utilization"Operating System Concepts!8.23! Silberschatz, Galvin and Gagne ©2005!
Page 1 and 2: The image cannot be displayed. Your
Page 5 and 6: Multistep Processing of a User Prog
Page 7 and 8: Memory-Management Unit (MMU)!Hardwa
Page 9 and 10: Swapping!A process can be swapped t
Page 11 and 12: Demand Paging!Bring a page into mem
Page 13 and 14: Valid-Invalid Bit!With each page ta
Page 15 and 16: Steps in Handling a Page Fault!Oper
Page 17 and 18: Important Dates!"" Apr 16 Prog Assi
Page 19 and 20: Contiguous Allocation!Main memory u
Page 21: HW address protection with base and
Page 25 and 26: Fragmentation!External Fragmentatio
Page 27 and 28: Address Translation Scheme!Address
Page 29 and 30: Paging Example !Operating System Co
Page 31 and 32: Free Frames!Before allocation"After
Page 33 and 34: Associative Memory! Associative mem
Page 35 and 36: Effective Access Time!Associative L
Page 37 and 38: Valid (v) or Invalid (i) Bit In A P
Page 39 and 40: Virtual Memory! Elusion to expand m
Page 41 and 42: Transfer of a Paged Memory to Conti
Page 43 and 44: Page Table When Some Pages Are Not
Page 45 and 46: What happens if there is no free fr
Page 47 and 48: Hierarchical Page Tables!Break up t
Page 49 and 50: Two-Level Page-Table Scheme!Operati
Page 51 and 52: Stop Here 4/23!Operating System Con
Page 53 and 54: Hashed Page Table!Operating System
Page 55 and 56: Inverted Page Table Architecture!Op
Page 57 and 58: Shared Pages Example!Operating Syst
Page 59 and 60: User’s View of a Program!Operatin
Page 61 and 62: Stop here!Operating System Concepts
Page 63 and 64: Segmentation Architecture (Cont.)!R
Page 65 and 66: Address Translation Architecture !O
Page 67 and 68: Sharing of Segments!Operating Syste
Page 69: MULTICS Address Translation Scheme!
Page 72 and 73:
Linux on Intel 80x86!Uses minimal s
show all

Chapter 8: Memory Management

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?