Gentoo Linux is a special flavor of Linux that can be automatically optimized and customized for just about any application or need. Extreme performance, configurability and a top-notch user and developer community are all hallmarks of the Gentoo experience. As a leader of Gentoo, I will provide an overview of how it works from a developer's and a user's point of view, and why you should be running it especially if you're: - In need of an awesome development environment; - Interested in learning what's inside the black box of Linux; - OCD about having a perfectly configured setup; or - Building an embedded, minimal system or a high-performance cluster. If there's interest, I can also talk about future developments on the horizon for Gentoo, package management in general, etc.

1. Gentoo Linux, or
Why in the World You Should
Compile Everything
Donnie Berkholz
Council Member & Sr. Developer
Gentoo Linux
dberkholz@gentoo.org
@dberkholz

2. Me in Gentoo

3. How I came to Gentoo

4. Overview

5. History

6. Gentoo features
• Beautiful splash screen, console and
colorful CLI
• Fully automated software installation
• Extremely easy maintenance
• Available in most architectures and OS's
• Configuration file protection and automerge

7. Gentoo features(con't)
• Advantages of compiling from source
• Multiple versions/implementations handling
• Binary package support

8. Portage features
• Customization of CFLAGS, LDFLAGS
• USE flags (more on that later)
• Various optional features - choose to suit
your own need through FEATURES variable
• Protection for live system
• FEATURES sandbox, collision-protect, protect-
owned
• Compilation speeding up
• FEATURES ccache, distcc
• System trimming
• FEATURES nodoc, noman, noinfo
• INSTALL_MASK

9. Portage features
(con't)
• SMP support
• emerge --jobs=JOBS --load-average=LOAD
• MAKEOPTS='-jN', where N is number of processors
+ 1
• FEATURES parallel-fetch
• Auto resuming after failure whenever
possible
• emerge --keep-going
• Blocker automatic solving
• com_err and ss V.S. e2fsprogs-libs
• Debugging support
• Adding "-g3 -ggdb3 -gdwarf-2" to CFLAGS
• FEATURES keepwork, nostrip, splitdebug,
installsources

10. Portage features
(con't)
• Embedded system support
• Features in portage 2.2
• License filtering
• Generic package sets
• FEATURES preserve-libs

11. Portage tree
• Gentoo's software repository
• One of the largest
• Bleeding edge packages
• Branches
• Overlays

12. Ebuild file
• Defines variables and functions used to
compile and install software
• KEYWORDS
• SLOT
• DEPEND, RDEPEND, PDEPEND
• LICENSE
• SRC_URI
• Functions - src_unpack(), src_compile(),
src_install()
• Eclasses

13. USE flags
• Map onto ./configure options
• Defaults defined by profile
• Define your own in addition to defaults
• Install only what you want
• Example:
• USE="-gnome kde qt -arts -nls"

14. Init system
• OpenRC
• Named run levels (boot, default)
• Smart dependencies
• Parallel startup
• Hotplug/Coldplug

15. Documentation
• Gentoo Handbook
• Desktop docs
• Upgrade guides
• System admin
• Developer docs
• Project docs

16. Gentoo Community
• Close contact with end users
• Many ebuilds submitted by users (sunrise
overlay)
• IRC
• Web forums
• Fully public bug tracking
• Developers attend FOSS events around the
world

17. Stay informed
• Main page - http://www.gentoo.org
• Planet - http://planet.gentoo.org
• Forums - http://forums.gentoo.org
• Gentoo Monthly Newsletter (GMN)
• http://www.gentoo.org/news/zh_cn/gmn/
• IRC channels
• http://www.gentoo.org/main/en/irc.xml
• Mailing lists
• http://www.gentoo.org/main/en/lists.xml
• Packages - http://packages.gentoo.org
• Gentoo Linux Security Announcements
(GLSA)

18. Is Gentoo for me?
• If you are lazy
• If you are a perfectionist
• If you like being in control
• If you want a stable and secure system
• If you want to know how a Unix-like
system works
• If you want to make the most out of your
hardware
• If you want to make your own distribution
• If you want to install GNU/Linux on your
PS3 and have it easily, regularly updated

19. EAPI: Ebuild API
• EAPI 0: Forever...
• EAPI 1: Nov 2007
• EAPI 2: Sept 2008
• EAPI 3: Jan 2010
• EAPI 4: Jan 2011

20. EAPI: Ebuild API
• 201499: single dependency variable
• DEPENDENCIES: “run+build: dev-libs/foo”
• 174412: remove EXPORT_FUNCTIONS
• Should be automated
• 179800: always-called eclass phase
functions
• Run something at src_prepare without making
sure ebuilds call $ECLASS_src_prepare when
overriding
• 185567: function to package source code
• Creating custom tarballs from upstream, e.g.
• 186454: move DESCRIPTION to metadata.xml
• package-wide, not per-ebuild

21. EAPI: Ebuild API
• 402167: move HOMEPAGE to metadata.xml
• 399019, 399307: move unpacking logic to
eclasses
• WIP
• remove need to dep on proper unpacker
• 354219: zero or one-of for REQUIRED_USE
• many cases of REQUIRED_USE would benefit from
a zero-of-or-one-of / at-most-one-of group.

22. Gentoo Linux, or
Why in the World You Should
Compile Everything
Donnie Berkholz
Council Member & Sr. Developer
Gentoo Linux
dberkholz@gentoo.org
@dberkholz

23. <http://dev.gentoo.org/~dberkholz/IntroToGentoo.odp>
Copyright 2006–2012 Rajiv Manglani, Zhang Le, Donnie
Berkholz. Some rights reserved.
The Gentoo Linux logo is Copyright 2002 Gentoo
Foundation, used with permission.
This work is licensed under the Creative Commons
Attribution-NonCommercial-ShareAlike License. To
view a copy of this license, visit <
http://creativecommons.org/licenses/by-nc-sa/2.0> or
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