GUADEC 2017 - Rolling Releases, The One True Way

Transcript

1. Richard Brown openSUSE Chairman rbrown@opensuse.org Rolling Releases The One True Way How I learned to stop worrying and love change
2. “How best to deliver software to users?”
3. In the Beginning
4. Distributing Sofware 101 • Users need some method or ‘unit’ of consumption of sofware • All Sofware is versioned • “Apps”, “Services”, “Operating Systems” - diferent names for similar units of sofware
5. Open Source, Unique Challenges Upstream sofware projects move very fast • Linux Kernel – New version every 3 months • GNOME – New version every 6 months • KDE Plasma – New version every 3 months • Docker – New version every 3 months • SaltStack – New version every 3-6 months
6. Anatomy of a Linux Distribution • “How to condense thousands of packages from thousands of diferent people into something which people can use?n” • Must be coherent, consistent, and operational • Linux Kernel + Toolchain + 1000’s of additional sofware packages
7. Regular Releases aka “Traditional Distributions” • Most Linux Distributions follow a “Regular Release” model • Release every X months/years • Freeze/Reluctantly upgrade package versions between Releases • Backport patches/fixes for frozen package versions • e.g. Debian, Fedora, openSUSE Leap, Ubuntu
8. Dev Branches • Most Linux Distributions rely on a Dev Branch to seed their Regular Releases • Always Released • Nothing Frozen/Backported • Normally Broken • e.g. Debian sid, Fedora Rawhide, openSUSE Factory, Ubuntu Daily
9. The Problems for Developers • Developers need their system to be as close as possible to their relevant upstream/distribution projects • Dev Branches accomplish this, but at the cost of stability • If it’s not stable, Developers will not use it, they have work to do
10. The Problems for Distributions • Fewer Users/Contributors of the Dev Branch is a serious, but common problem • Fewer bugs found before each Regular Release • Less innovation/new features in your codebase • Increasing Technical Debt, making each Release more ‘expensive’ to clear that debt • Stagnation/Decline, ofen with very public development probs
11. The Problems for Upstream Developers • Upstream Developers want to put their sofware in the hands of users as fast as possible • Dev Branches do not accomplish this, neither do Regular Releases • Containerised Apps promise to solve this, but it’s not that easy
12. The Problems for Users • Many Linux Users are enthusiasts with a keen interest in the upstream projects of their choice • These users don’t want to wait, but when they use it they want it to work • Consistency, ‘well put together’, ‘feels right’, UX, are key requirements • These enthusiasts are the prime candidates to become contributors of tomorrow
13. Rolling Releases to the Rescue
14. Rolling Releases to the Rescue • No Release Schedule • Frequent Updates to all Packages • Updates delivered “when they're ready” • e.g. Arch, Gentoo, openSUSE Tumbleweed
15. Rolling Releases – Common Problems • Unstable • Unreliable • Hard to Live With
16. Unstable • “Always Changing” • A fast moving codebase is going to include changes, that’s the point • Changes must be built, tested, and integrated consistently • Users must be shielded from behavioural changes so they can just focus on getting their work done, then change when they’re ready
17. Unreliable • “Always Breaking” • Thousands of moving parts from thousands of upstream projects are a challenge to get working together • Changes must be built, tested, and integrated consistently • Test-at-the-submission & Test-as-a-whole; Distributions are not a collection of packages, but a cohesive product • Users must not be shipped something that doesn’t work
18. Passive Testing is not good enough! • Many distributions, incl. rolling releases, rely on “Passive Testing” • Put new packages in a “Testing Branch”, wait X days then assume “it’s good enough” and ship! • Works better or worse depending on size of developer & testing communities • Still basically Russian Roulette
19. Active Testing is required Rolling Releases SHOULD actively confirm: – “does the new package break something in isolation?n” – “does the new package break something when installed in a broader context?n” – “does the new package change behaviour users expect?n” • Answers to the above questions needed ideally BEFORE an Upstream Release or ASAP afer
20. Hard to Live With • The Arch Way - “Do it yourself, it’s a learning exercise” • The Gentoo Way - “Do it yourself, and you can read the Arch wiki while everything is compiling” • Something went wrong or changed in a way you don’t like?n Too bad, good luck undoing it, you can always start again
21. “Who said Rolling Releases needed to be difficult?”
22. Enter Tumbleweed
23. A Brief History of Tumbleweed • Originally created by Greg Kroah-Hartman • Merged with the 'Factory' rolling release on November 4th 2014 • Provides the latest updates 'at the pace of contribution', without the risk of major system issues • Tested by openQA continuously • Developer, Contributor & Enthusiast focus
24. OG Tumbleweed (Pre Nov 2014) • Tumbleweed was originally 'rolling updates' based on regular releases • Required an additional repository to your ‘traditional’ openSUSE release • Focus on Kernel, KDE, GNOME and some Apps • Would overwrite packages from regular release • “Reset-to-zero” every regular release
25. Original Tumbleweed, Original Troubles • “Partially-Rolling” does not work • Constant breakage over the growing chasm between the ‘stable base’ and ‘rolling top’ • Ad-hoc tinkering of the ‘stable base’ stops it being stable • “Reset-to-zero” rebase to a new stable base every 8 months was brutally disruptive for many users
26. Richard’s Rolling Release Rule “In order to move ANYTHING quickly, you need to be able to move EVERYTHING quickly”
27. Building Linux Better • Open Build Service started in February 2006 • Used to build the openSUSE® & SUSE® distributions • Can also build packages for other distributions (Fedora/Red Hat, Ubuntu, Debian, Arch, etc) • Also used by ownCloud, Linux Foundation, VideoLAN (VLC), Dell, Cray, Intel and more. http://openbuildservice.org
28. Testing Linux Better • openQA started in November 2009 • Able to fully test Linux distributions from install to user applications • Integral part of the openSUSE® Tumbleweed & Leap process • Used by SUSE® to test SUSE Linux Enterprise • Recently adopted by Red Hat to test Fedora http://open.qa
33. Help make openQA & Tumbleweed better • Main Website – http://open.qa • Documentation – http://open.qa/documentation/ • Bug Reports & Feature Requests – https://progress.opensuse.org/projects/openqav3
34. DevOps OS Development
35. “Fancy, but I don’t want to wait for all that build & test nonsense”
36. Working with Upstream Projects • GNOME 3.22 – Shipped <48 hours afer Upstream Release • KDE Plasma 5.9 – Shipped on Upstream Release Day • “GNOME:Next” – Tumbleweed derivative testing GNOME git – LiveCD’s provided for Upstream Release Day • openSUSE Krypton – Tumbleweed derivative testing KDE git
37. A “quiet” Tumbleweek • 3 Snapshots • 146 Package Updates • 15 New Packages on the DVD • 38 Packages Removed from the DVD • 1 new Kernel
38. A “quiet” Tumbleweek • 3 Snapshots • 146 Package Updates • 15 New Packages on the DVD • 38 Packages Removed from the DVD • 1 new Kernel QUIET?!
39. Another Tumbleweek • 5 Snapshots • 298 Package Updates • 47 New Packages on the DVD • 42 Packages Removed from the DVD • 2 new Kernels
40. btrfs & snapper – our secret sauce • Tumbleweeds default install uses btrfs & snapper • Automatically configured to snapshot root filesystem when packages are installed • Unwanted changes can be safely rolled back, even from GRUB
41. “What about openSUSE Factory?”
42. Who needs a Dev Branch anyway? + = Tumbleweed
43. “What about the openSUSE Regular Release?”
44. Tumbleweed
45. The New openSUSE Distributions • openSUSE Tumbleweed – Rolling Release – Continuously Updated & Tested – Perfect for Developers & Power Users • openSUSE Leap – Regular Release – Shared Core with SUSE Linux Enterprise – Perfect for SysAdmins, Enterprise Developers, and Users Tumbleweed
46. SUSE® Linux Enterprise
47. Tumbleweed Shared Core >8000 Packages Community Developed Rolling Updates Rolling Base System openSUSE Leap Over 6000 Packages Community Developed SUSE® Linux Enterprise Enterprise Packages SUSE Developed Stable Base System Regular Updates Stable Base System Regular Updates Shared Core
48. Tumbleweed and SUSE Linux Enterprise SLE 15 Leap 15.0 openSUSE Tumbleweed Leap 42.2 SLE 12 SP2 Core 12.2 Leap 42.3 SLE 12 SP3 Core 12.3 Core 15
49. In Review
50. Tumbleweed for Developers • Keep close to your chosen upstream projects • Get the latest and greatest versions of everything • “It just works”, and if it doesn’t work the way you want any more, snapper rollbacks keep you working • Something not quite perfect?n Please contribute back, so we can help make Tumbleweed even better for you
51. Tumbleweed for Upstream Developers • Roll with us and you get packaging experts to help, cross-distro packaging tools, and unparalleled automated functional testing • Containerised Applications are cool for those ‘other’ distributions, but are more work for you
52. Tumbleweed for Users • Get the latest and greatest versions of everything • “It just works”, and if it doesn’t work the way you want any more, snapper rollbacks keep you working • Having a lot of fun?n Please contribute back, so we can help make Tumbleweed even better for you
54. “Rolling Releases are the future of Linux Distributions”
55. Join Us at www.opensuse.org
56. License This slide deck is licensed under the Creative Commons Attribution-ShareAlike 4.0 International license. It can be shared and adapted for any purpose (even commercially) as long as Attribution is given and any derivative work is distributed under the same license. Details can be found at https://creativecommons.org/licenses/by-sa/4.0/ General Disclaimer This document is not to be construed as a promise by any participating organisation to develop, deliver, or market a product. It is not a commitment to deliver any material, code, or functionality, and should not be relied upon in making purchasing decisions. openSUSE makes no representations or warranties with respect to the contents of this document, and specifically disclaims any express or implied warranties of merchantability or fitness for any particular purpose. The development, release, and timing of features or functionality described for openSUSE products remains at the sole discretion of openSUSE. Further, openSUSE reserves the right to revise this document and to make changes to its content, at any time, without obligation to notify any person or entity of such revisions or changes. All openSUSE marks referenced in this presentation are trademarks or registered trademarks of SUSE LLC, in the United States and other countries. All third-party trademarks are the property of their respective owners. Credits Template Richard Brown rbrown@opensuse.org Design & Inspiration openSUSE Design Team http://opensuse.github.io/branding- guidelines/