How I Learned

To Stop

Worrying And Love The

Linux

Helen Tabunshchyk

• MSc in Computer Engineering

• Senior Software Developer • In industry since 2011 • Now specializing in high

performance • Commercial experience: C,

C++, Python, Boost, OpenCV, Qt, AMQP, RDBMS, NoSQL, Linux <3, #ihavenospaceleft

• Also into: VHDL, Erlang, Rust, machine learning, embedded, robotics and other fun stuff

History of Linux

UNIX

“Those who do not understand UNIX are condemned to reinvent

it, poorly.”

(c) Henry Spencer

• 1969: Ken Thompson, Dennis Ritchie and

others started working on the "little-

used PDP-7 in a corner" at Bell Labs

and what was to become UNIX.

• 1973: It was rewritten in C. This made

it portable and changed the history of

OS’s.

• Its architecture did not change much

till now (2017 AD, i.e. 47 years).

The Unix Philosophy

(c) Doug McIlroy

• Make each program do one thing well.

• Expect the output of every program to

become the input to another, as yet

unknown, program.

• Design and build software to be tried

early.

• Use tools in preference to unskilled

help to lighten a programming task.

“The whole philosophy of UNIX seems to stay out of

assembler.”

(c) Joseph Henry Condon

GNU

• 1983: Richard Stallman started the GNU project with the goal of creating a free UNIX-like operating system.

• Freedom rights: users are free to run the software, share it (copy, distribute), study it and modify it.

• By the early 1990s the GNU kernel failed to attract enough development effort, leaving GNU incomplete.

MINIX

• 1987: MINIX, a Unix-like system

intended for academic use, was

released by Andrew S. Tanenbaum to

exemplify the principles conveyed in

his textbook, Operating Systems:

Design and Implementation.

• While source code for the system was

available, modification and

redistribution were restricted.

Linux

• 1991: The Linux kernel is publicly

announced by the 21-year-old Finnish

student Linus Benedict Torvalds.

• 1992: The Linux kernel is relicensed

under the GNU GPL. The first Linux

distributions are created.

• 1994: 150,000 lines of code.

• 2017: 25+ million lines of code.

Linux Distributions

278 registered

Popularity

• 95% of all supercomputers

• 37% of websites

• 87.5% of global smartphone

market share (Android)

• 4% of desktop systems

System Requirements

• Intel 80386

• 2 megabytes of RAM

• Any video card

Minimum as in 1992

28 processor architectures

Now

Why Linux is so awesome?

Except it is completely open

and free

Monolithic Kernel

Security

User Privileges

• Linux Security Modules

(SELinux, AppArmor, Smack,

TOMOYO Linux and Yama)

• Firewall

• Memory protection

• chroot’ing a process

Linux Is a Fine-tunable System

• More than 600 penetration testing

tools included

• Custom kernel, patched for wireless

injection

• Developed in a secure environment

• GPG signed packages and repositories

• Single user, root access by design

• Network services (incl. bluetooth)

disabled by default

Kali Linux

• The central resource for open source software information, best practices, how-to’s: linux.com.

• The Linux Foundation YouTube channel: youtube.com/user/TheLinuxFoundation.

• The Art of Unix Programming. Book by Eric Steven Raymond.

• Systems Performance: Enterprise and the Cloud. Book by Brendan Gregg.

• Understanding the Linux kernel. Book by Daniel P. Bovet and Marco Cesati.

• Tech Blog “High Scalability”: highscalability.com.

Recommended Resources

Thank you!

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