1. Pertemuan 12 Manajemen Memory (Lanjutan)
Matakuliah : T0316/sistem Operasi
Tahun : 2005
Versi/Revisi : 5
Pertemuan 12 Manajemen Memory (Lanjutan)
OFFCLASS02

2. Learning Outcomes
Pada akhir pertemuan ini, diharapkan mahasiswa
akan mampu :
menjelaskan pengelolaan memory tingkat lanjut, misalnya swapping, virtual memory (C2)

3. Outline Materi
Swaping
Memory management dgn Bit Map
Memory management dgn Linked List
Algoritma pengalokasian memori
Virtual memory
Page table

4. Swapping (1) Memory allocation changes as
processes come into memory
leave memory
Shaded regions are unused memory

5. Swapping (2) Allocating space for growing data segment
Allocating space for growing stack & data segment

6. Memory Management with Bit Maps
Part of memory with 5 processes, 3 holes
tick marks show allocation units
shaded regions are free
Corresponding bit map
Same information as a list

7. Memory Management with Linked Lists
Four neighbor combinations for the terminating process X

8. Algorithm for memory allocation
First Fit
Next Fit
Best Fit
Worst Fit
Quick Fit
To speed-up search:
Separate table for process and holes
Hole list is sorted (eg ascending)
 Best fit = first fit; next fit is unnecessary

9. Virtual Memory Paging (1)
The position and function of the MMU

10. Paging (2)
The relation between virtual addresses and physical memory addresses given by page table

11. Page Tables (1)
Internal operation of MMU with 16 4 KB pages

12. Page Tables (2) 32 bit address with 2 page table fields
Second-level page tables
Top-level
page table
32 bit address with 2 page table fields
Two-level page tables

13. Typical page table entry
Page Tables (3)
Typical page table entry

14. TLBs – Translation Lookaside Buffers
A TLB to speed up paging

15. Inverted Page Tables
Comparison of a traditional page table with an inverted page table