Transcript OS-2-by-Keith-Ancowitz-Brian-Henderson-James-Mauss

OS/2
CS-450-3 Operating Systems
Section 3 Fall 2003
By
Keith Ancowitz
Brian Henderson
James Mauss
Danielle Miller
Kyle Nevins
Outline
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OS/2 History
File Management System
Memory Management
Process Management
Scheduler
OS/2 Warp History
OS/2 1.0
Began as a joint venture with Microsoft to replace the
current DOS 3.x system.
OS/2 1.1
First implementation of a GUI in the operating
system.
OS/2 1.3
First version of OS/2 released by IBM without
Microsoft’s assistance.
OS/2 2.0
First version of the 32-bit system.
OS/2 2.1
Released to allow users to have Windows 3.1
compatibility.
OS/2 Warp 3.0
First version of Warp to appear.
OS/2 Warp Connect
P2P functionality and networking support.
OS/2 Warp 4.0
Included Java and VoiceType
OS/2 vs. DOS File Systems
OS/2 v1.2
DOS
File System
High Performance File System (HPFS)
File Allocation Table (FAT)
Max. Characters in
Filename
255
11
Filename Format
Capable of multiple extensions of varying lengths.
This.my.filename
8dot3 (8 character filename and a single 3
character extension)
Max. Path Length
260
64
File and Dir Tracking
Sector Level
Cluster Level
File Attributes
Last Modified, Type of Data Stored, Native Language,
etc.
Min. Allocation Unit
Sector (512 bytes) ≈ file node (FNODE)
Cluster (4kb or more)
Directory Structure
Sorted Binary Tree
Unsorted Linear List
Caching Technique
Store entire file and dir structure in cache
File System Update
Installable File System
N/A
XCOPY for a 5 MB file
21.6 Seconds
39.4 Seconds
Build an index of 4600
records in a 2.3 MB file
161 Seconds
973 Seconds
Installable File System
Memory Management
Selector
13
1
Offset
32
2
13 bit number for the segment number
1 bit to tell which table to look in LDT or GDT
2 bits to deal with protection
Segment Table
+
Linear Address
Page Number
10
10
Page offset
12
Physical Address
Page Directory
Page Frame
Page Table
SMP
Symmetrical Multi-Processing
• Testing Applications
• Increased Performance for Cheaper
• “Greatest Advantage” of OS/2 over Windows
Process/
Page
Life
Cycle
Process Scheduling
• RING 3 Scheduling
– Four types of threads
• Normal Level
– 32 microseconds
• Time Critical
– 8 microseconds
• Idle-time
• Foreground Server
– Priority and Round Robin
Process Scheduling
• RING 0 Scheduling
– Same Levels
– Contexts
• Init Mode
• Interrupt Mode
– Highest Priority
– Dependant on IRQ levels
• Kernel Mode