RONG LIU

(Operating System Comparison)

Introduction(1)

What is Linux?

The free UNIX written from scratch by Linus Torvalds, assistance from a loosely-knit team of hackers from across the internet.

A modern, fully fledged UNIX: true multitasking, virtual memory, shared libraries, demand loading, shared, copy-on-write executables, proper memory management, and TCP/IP networking.

Introduction(2)

History of Unix

• In April, 1969, Ken Thompson, Brian Kernighan and Dennis Ritchie sketched out an operating system that would meet Bell Labs' needs, soon become Unix.

• In 1973, UNIX, was rewritten in C as Version 4 by Dennis Ritchie and Brian Kernighan.• Two major hot-beds of Unix development were at the University of California, Berkeley, which later became BSD (Berkeley Software Distribution), and M.I.T., which eventually gave us the Free Software Foundation and the GNU project, and the X Window System.

Introduction(2) (Cont...)

History of Unix

• Unix today has two major versions: System V (or SVR4 from Unix System) and BSD (Berkeley Software Distribution).

• UNIX (upper case) is a trademark of The Open Group.

• Unix refers to Unix versions in general, regardless of the source; usually it is simply referred to as SVR4 or BSD 4.4.

Linux operating system overview

• Memory Management:– Page Allocation– The Linux Page Cache– The Swap Cache

• Processes• The Linux Networking• Linux PCI Initialization

Processes

Processes have following states: • Running• Waiting• Stopped• Zombie

The Linux Networking

Linux supports the following socket address families or domains:

• UNIX -- Unix domain sockets.• INET -- communications via TCP/IP.• AX25 -- Amateur radio X25.• IPX -- Novell IPX• AppleTalk -- AppleTalk DDP• X25 -- X25

Linux PCI Initialization

PCI Device Driver A. builds a linked list of data structures describing the

topology of the system. B. numbers all of the bridges that it finds.

PCI BIOS provides the services described in bib-pci-bios-specification.

PCI Fixup tidies up the system specific loose ends of PCI

initialization.

Unix operating system overview

OS Structure File System Directories Structure Common Control Keys Unix Shells

Unix OS Structure

Hardware

Kernel

Shell Editors,

Private User programsC

ompi

ler

Com

pone

nts

Com

pile

r

Unix file system

Unix Directories Structure

1). Every directory and file is listed in its parent directory.

2). Each file assigned inode number, an inode is a special file designed to be read by the kernel to learn the information about each file.

3). The system does not require any particular structure for the data in the file itself. i.e. It can be ASCII, binary or a combination.

4). There's no header, trailer, label information or EOF character as part of the file.

-C: Standard interrupt key;

-U: The key deletes the entire line;

-H: Use to erase the characters;

-W: Deletes the word you are entering;

-R: Moves cursor to next line;

-D: Logs out from shell prompt;

-S: Stops terminal accepting input;

-Q: Starts terminal accepting input.

Unix Common Control Keys

CONTROL

CONTROL

CONTROL

CONTROL

CONTROL

CONTROL

CONTROL

CONTROL

Unix Shells

The shell sits between you and the operating system, acting as a command interpreter. The common shells as follow:

1). Bourne shell, sh($) was the original shell. 2). C shell prompt is %. 3). Korn shell, ksh has nearly all the features

of Bourne Shell, maximixes execution speed of scripts.

Linux compares with Unix

The File systemsShared Virtual Memory

Inter-Process Communication

Identifiers

Executing Programs

EXT2 File System

Similarity of Linux and Unix

Compare Linux2.2 with Solaris7.0(1)

OS convenience

Bugfixes and other updates

Linux 2.2 Solaris 7.0

Freely download able, and available on CD. Both a stable and a bleeding-edge version is available.

Some (all???) minor updates/bugfixes can be downloaded freely.Subscription customers get's major upgrades on CD.

Run a GUI app on one machineDiaplay it on another .

yes yes

Virus no no

Compare Linux2.2 with Solaris7.0(2)

OS

Single Unix Specification v.1

(UNIX95)

Linux 2.2 Solaris 7.0

Single Unix Specification v.2

(UNIX98)

yes

Address space

no no

no

no

yes

Multiple CPU's SMP up to 16 CPU's, much improved performance in comparison to 2.0.*, clustering SMP on both Sparc and Intel 64 CPU's on

sparcMax. file size

2 GB (ext2) 1 TB (on UltraSparc)

Max. file system size 16 TB (ext2) 1 TB (on UltraSparc)

OS FlavorDesigned from scratch to be Posix and now Unix98 compliant.

Has some backwards SysV R4

Compare Linux2.2 with Solaris7.0(3)

OS(Con.)

Linux 2.2 Solaris 7.0

Memory protection Yes Yes

POSIX.1 certification

A posix.1 certified Linux 2.0.* kernel is available from Unifix.The main kernel is designed to be posix complient, but haven't been certified.

Yes

Threads posix 1003.1c posix 1003.1c

XPG4 base 95

no Yes

Compare Linux2.2 with Solaris7.0(4)

Provider

Linux 2.2 Solaris 7.0

ManufactorDeveloped, programmed and maintained by a big group of people from all over the world.

Sun Microsystems Inc.901 San Antonio RoadPalo AltoCA 94303 USA

Pricing free

pay-ware or 2 year subscriptions

Compare Linux2.2 with Solaris7.0(5)

Hardware

Linux 2.2 Solaris 7.0

Peripherals Most PC hardware.

All current Sparc peripherals, some PC peripherals.

PlatformsPC >= 386, Digital Alpha, Sparc, UltraSparc, PPC, StrongARMMore are in development

Sparc and PC >= 386

Reference:

1)."Linux at work ( building Strategic Applications for Business)" by Marcus Concalves.

2). "Peter Norton's Complete Guide to Linux" by Peter Norton and Arthur Grifficth.

3). “UNIX System V(Practical Guide) “by Mark G. Sobell.

4). “Operating Systems” by William Stallings.

5). Web page at http://www.cs.utexas.edu.

6). Web page at http://www.idealcorp.com.

7). Web page at http://www.Linuxrx.org.