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1485 lines
55 KiB
ReStructuredText
1485 lines
55 KiB
ReStructuredText
============================================
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Contributing to Ceph: A Guide for Developers
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============================================
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:Author: Loic Dachary
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:Author: Nathan Cutler
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:License: Creative Commons Attribution-ShareAlike (CC BY-SA)
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.. note:: The old (pre-2016) developer documentation has been moved to :doc:`/dev/index-old`.
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.. contents::
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:depth: 3
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Introduction
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============
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This guide has two aims. First, it should lower the barrier to entry for
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software developers who wish to get involved in the Ceph project. Second,
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it should serve as a reference for Ceph developers.
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We assume that readers are already familiar with Ceph (the distributed
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object store and file system designed to provide excellent performance,
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reliability and scalability). If not, please refer to the `project website`_
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and especially the `publications list`_.
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.. _`project website`: http://ceph.com
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.. _`publications list`: https://ceph.com/resources/publications/
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Since this document is to be consumed by developers, who are assumed to
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have Internet access, topics covered elsewhere, either within the Ceph
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documentation or elsewhere on the web, are treated by linking. If you
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notice that a link is broken or if you know of a better link, please
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`report it as a bug`_.
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.. _`report it as a bug`: http://tracker.ceph.com/projects/ceph/issues/new
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Essentials (tl;dr)
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==================
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This chapter presents essential information that every Ceph developer needs
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to know.
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Leads
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-----
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The Ceph project is led by Sage Weil. In addition, each major project
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component has its own lead. The following table shows all the leads and
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their nicks on `GitHub`_:
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.. _github: https://github.com/
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========= =============== =============
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Scope Lead GitHub nick
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========= =============== =============
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Ceph Sage Weil liewegas
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RADOS Samuel Just athanatos
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RGW Yehuda Sadeh yehudasa
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RBD Jason Dillaman dillaman
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CephFS John Spray jcsp
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Build/Ops Ken Dreyer ktdreyer
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========= =============== =============
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The Ceph-specific acronyms in the table are explained in
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:doc:`/architecture`.
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History
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-------
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See the `History chapter of the Wikipedia article`_.
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.. _`History chapter of the Wikipedia article`: https://en.wikipedia.org/wiki/Ceph_%28software%29#History
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Licensing
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---------
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Ceph is free software.
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Unless stated otherwise, the Ceph source code is distributed under the terms of
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the LGPL2.1. For full details, see `the file COPYING in the top-level
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directory of the source-code tree`_.
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.. _`the file COPYING in the top-level directory of the source-code tree`:
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https://github.com/ceph/ceph/blob/master/COPYING
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Source code repositories
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------------------------
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The source code of Ceph lives on `GitHub`_ in a number of repositories below
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the `Ceph "organization"`_.
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.. _`Ceph "organization"`: https://github.com/ceph
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To make a meaningful contribution to the project as a developer, a working
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knowledge of git_ is essential.
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.. _git: https://git-scm.com/documentation
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Although the `Ceph "organization"`_ includes several software repositories,
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this document covers only one: https://github.com/ceph/ceph.
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Redmine issue tracker
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---------------------
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Although `GitHub`_ is used for code, Ceph-related issues (Bugs, Features,
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Backports, Documentation, etc.) are tracked at http://tracker.ceph.com,
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which is powered by `Redmine`_.
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.. _Redmine: http://www.redmine.org
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The tracker has a Ceph project with a number of subprojects loosely
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corresponding to the various architectural components (see
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:doc:`/architecture`).
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Mere `registration`_ in the tracker automatically grants permissions
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sufficient to open new issues and comment on existing ones.
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.. _registration: http://tracker.ceph.com/account/register
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To report a bug or propose a new feature, `jump to the Ceph project`_ and
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click on `New issue`_.
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.. _`jump to the Ceph project`: http://tracker.ceph.com/projects/ceph
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.. _`New issue`: http://tracker.ceph.com/projects/ceph/issues/new
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Mailing list
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------------
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Ceph development email discussions take place on the mailing list
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``ceph-devel@vger.kernel.org``. The list is open to all. Subscribe by
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sending a message to ``majordomo@vger.kernel.org`` with the line: ::
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subscribe ceph-devel
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in the body of the message.
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There are also `other Ceph-related mailing lists`_.
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.. _`other Ceph-related mailing lists`: https://ceph.com/resources/mailing-list-irc/
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IRC
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---
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In addition to mailing lists, the Ceph community also communicates in real
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time using `Internet Relay Chat`_.
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.. _`Internet Relay Chat`: http://www.irchelp.org/
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See https://ceph.com/resources/mailing-list-irc/ for how to set up your IRC
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client and a list of channels.
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Submitting patches
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------------------
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The canonical instructions for submitting patches are contained in the
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`the file CONTRIBUTING.rst in the top-level directory of the source-code
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tree`_. There may be some overlap between this guide and that file.
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.. _`the file CONTRIBUTING.rst in the top-level directory of the source-code tree`:
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https://github.com/ceph/ceph/blob/master/CONTRIBUTING.rst
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All newcomers are encouraged to read that file carefully.
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Building from source
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--------------------
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See instructions at :doc:`/install/build-ceph`.
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Using ccache to speed up local builds
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-------------------------------------
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Rebuilds of the ceph source tree can benefit significantly from use of `ccache`_.
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Many a times while switching branches and such, one might see build failures for
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certain older branches mostly due to older build artifacts. These rebuilds can
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significantly benefit the use of ccache. For a full clean source tree, one could
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do ::
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$ make clean
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# note the following will nuke everything in the source tree that
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# isn't tracked by git, so make sure to backup any log files /conf options
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$ git clean -fdx; git submodule foreach git clean -fdx
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ccache is available as a package in most distros. To build ceph with ccache one
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can::
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$ cmake -DWITH_CCACHE=ON ..
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ccache can also be used for speeding up all builds in the system. for more
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details refer to the `run modes`_ of the ccache manual. The default settings of
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``ccache`` can be displayed with ``ccache -s``.
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.. note: It is recommended to override the ``max_size``, which is the size of
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cache, defaulting to 10G, to a larger size like 25G or so. Refer to the
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`configuration`_ section of ccache manual.
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.. _`ccache`: https://ccache.samba.org/
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.. _`run modes`: https://ccache.samba.org/manual.html#_run_modes
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.. _`configuration`: https://ccache.samba.org/manual.html#_configuration
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Development-mode cluster
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------------------------
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See :doc:`/dev/quick_guide`.
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Backporting
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-----------
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All bugfixes should be merged to the ``master`` branch before being backported.
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To flag a bugfix for backporting, make sure it has a `tracker issue`_
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associated with it and set the ``Backport`` field to a comma-separated list of
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previous releases (e.g. "hammer,jewel") that you think need the backport.
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The rest (including the actual backporting) will be taken care of by the
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`Stable Releases and Backports`_ team.
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.. _`tracker issue`: http://tracker.ceph.com/
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.. _`Stable Releases and Backports`: http://tracker.ceph.com/projects/ceph-releases/wiki
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What is merged where and when ?
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===============================
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Commits are merged into branches according to criteria that change
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during the lifecycle of a Ceph release. This chapter is the inventory
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of what can be merged in which branch at a given point in time.
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Development releases (i.e. x.0.z)
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---------------------------------
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What ?
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^^^^^^
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* features
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* bug fixes
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Where ?
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^^^^^^^
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Features are merged to the master branch. Bug fixes should be merged
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to the corresponding named branch (e.g. "jewel" for 10.0.z, "kraken"
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for 11.0.z, etc.). However, this is not mandatory - bug fixes can be
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merged to the master branch as well, since the master branch is
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periodically merged to the named branch during the development
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releases phase. In either case, if the bugfix is important it can also
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be flagged for backport to one or more previous stable releases.
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When ?
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^^^^^^
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After the stable release candidates of the previous release enters
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phase 2 (see below). For example: the "jewel" named branch was
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created when the infernalis release candidates entered phase 2. From
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this point on, master was no longer associated with infernalis. As
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soon as the named branch of the next stable release is created, master
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starts getting periodically merged into it.
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Branch merges
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^^^^^^^^^^^^^
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* The branch of the stable release is merged periodically into master.
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* The master branch is merged periodically into the branch of the
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stable release.
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* The master is merged into the branch of the stable release
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immediately after each development x.0.z release.
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Stable release candidates (i.e. x.1.z) phase 1
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----------------------------------------------
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What ?
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^^^^^^
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* bug fixes only
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Where ?
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^^^^^^^
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The branch of the stable release (e.g. "jewel" for 10.0.z, "kraken"
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for 11.0.z, etc.) or master. Bug fixes should be merged to the named
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branch corresponding to the stable release candidate (e.g. "jewel" for
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10.1.z) or to master. During this phase, all commits to master will be
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merged to the named branch, and vice versa. In other words, it makes
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no difference whether a commit is merged to the named branch or to
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master - it will make it into the next release candidate either way.
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When ?
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^^^^^^
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After the first stable release candidate is published, i.e. after the
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x.1.0 tag is set in the release branch.
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Branch merges
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^^^^^^^^^^^^^
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* The branch of the stable release is merged periodically into master.
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* The master branch is merged periodically into the branch of the
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stable release.
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* The master is merged into the branch of the stable release
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immediately after each x.1.z release candidate.
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Stable release candidates (i.e. x.1.z) phase 2
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----------------------------------------------
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What ?
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^^^^^^
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* bug fixes only
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Where ?
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^^^^^^^
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The branch of the stable release (e.g. "jewel" for 10.0.z, "kraken"
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for 11.0.z, etc.). During this phase, all commits to the named branch
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will be merged into master. Cherry-picking to the named branch during
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release candidate phase 2 is done manually since the official
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backporting process only begins when the release is pronounced
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"stable".
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When ?
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^^^^^^
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After Sage Weil decides it is time for phase 2 to happen.
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Branch merges
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^^^^^^^^^^^^^
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* The branch of the stable release is merged periodically into master.
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Stable releases (i.e. x.2.z)
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----------------------------
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What ?
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^^^^^^
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* bug fixes
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* features are sometime accepted
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* commits should be cherry-picked from master when possible
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* commits that are not cherry-picked from master must be about a bug unique to the stable release
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* see also `the backport HOWTO`_
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.. _`the backport HOWTO`:
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http://tracker.ceph.com/projects/ceph-releases/wiki/HOWTO#HOWTO
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Where ?
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^^^^^^^
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The branch of the stable release (hammer for 0.94.x, infernalis for 9.2.x, etc.)
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When ?
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^^^^^^
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After the stable release is published, i.e. after the "vx.2.0" tag is
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set in the release branch.
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Branch merges
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^^^^^^^^^^^^^
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Never
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Issue tracker
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=============
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See `Redmine issue tracker`_ for a brief introduction to the Ceph Issue Tracker.
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Ceph developers use the issue tracker to
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1. keep track of issues - bugs, fix requests, feature requests, backport
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requests, etc.
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2. communicate with other developers and keep them informed as work
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on the issues progresses.
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Issue tracker conventions
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-------------------------
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When you start working on an existing issue, it's nice to let the other
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developers know this - to avoid duplication of labor. Typically, this is
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done by changing the :code:`Assignee` field (to yourself) and changing the
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:code:`Status` to *In progress*. Newcomers to the Ceph community typically do not
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have sufficient privileges to update these fields, however: they can
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simply update the issue with a brief note.
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.. table:: Meanings of some commonly used statuses
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================ ===========================================
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Status Meaning
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================ ===========================================
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New Initial status
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In Progress Somebody is working on it
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Need Review Pull request is open with a fix
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Pending Backport Fix has been merged, backport(s) pending
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Resolved Fix and backports (if any) have been merged
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================ ===========================================
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Basic workflow
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==============
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The following chart illustrates basic development workflow:
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.. ditaa::
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Upstream Code Your Local Environment
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/----------\ git clone /-------------\
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| Ceph | -------------------------> | ceph/master |
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\----------/ \-------------/
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^ |
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| | git branch fix_1
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| git merge |
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/----------------\ git commit --amend /-------------\
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| make check |---------------------> | ceph/fix_1 |
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| ceph--qa--suite| \-------------/
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\----------------/ |
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^ | fix changes
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| | test changes
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| review | git commit
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/--------------\ /-------------\
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| github |<---------------------- | ceph/fix_1 |
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| pull request | git push \-------------/
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\--------------/
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Below we present an explanation of this chart. The explanation is written
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with the assumption that you, the reader, are a beginning developer who
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has an idea for a bugfix, but do not know exactly how to proceed.
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Update the tracker
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------------------
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Before you start, you should know the `Issue tracker`_ number of the bug
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you intend to fix. If there is no tracker issue, now is the time to create
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one.
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The tracker is there to explain the issue (bug) to your fellow Ceph
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developers and keep them informed as you make progress toward resolution.
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To this end, then, provide a descriptive title as well as sufficient
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information and details in the description.
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If you have sufficient tracker permissions, assign the bug to yourself by
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changing the ``Assignee`` field. If your tracker permissions have not yet
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been elevated, simply add a comment to the issue with a short message like
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"I am working on this issue".
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Upstream code
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-------------
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This section, and the ones that follow, correspond to the nodes in the
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above chart.
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The upstream code lives in https://github.com/ceph/ceph.git, which is
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sometimes referred to as the "upstream repo", or simply "upstream". As the
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chart illustrates, we will make a local copy of this code, modify it, test
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our modifications, and submit the modifications back to the upstream repo
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for review.
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A local copy of the upstream code is made by
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1. forking the upstream repo on GitHub, and
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2. cloning your fork to make a local working copy
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See the `the GitHub documentation
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<https://help.github.com/articles/fork-a-repo/#platform-linux>`_ for
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detailed instructions on forking. In short, if your GitHub username is
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"mygithubaccount", your fork of the upstream repo will show up at
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https://github.com/mygithubaccount/ceph. Once you have created your fork,
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you clone it by doing:
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.. code::
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$ git clone https://github.com/mygithubaccount/ceph
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While it is possible to clone the upstream repo directly, in this case you
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must fork it first. Forking is what enables us to open a `GitHub pull
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request`_.
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For more information on using GitHub, refer to `GitHub Help
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<https://help.github.com/>`_.
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Local environment
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-----------------
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In the local environment created in the previous step, you now have a
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copy of the ``master`` branch in ``remotes/origin/master``. Since the fork
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(https://github.com/mygithubaccount/ceph.git) is frozen in time and the
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upstream repo (https://github.com/ceph/ceph.git, typically abbreviated to
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``ceph/ceph.git``) is updated frequently by other developers, you will need
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to sync your fork periodically. To do this, first add the upstream repo as
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a "remote" and fetch it::
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$ git remote add ceph https://github.com/ceph/ceph.git
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$ git fetch ceph
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Fetching downloads all objects (commits, branches) that were added since
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the last sync. After running these commands, all the branches from
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``ceph/ceph.git`` are downloaded to the local git repo as
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``remotes/ceph/$BRANCH_NAME`` and can be referenced as
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``ceph/$BRANCH_NAME`` in certain git commands.
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For example, your local ``master`` branch can be reset to the upstream Ceph
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``master`` branch by doing::
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$ git fetch ceph
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$ git checkout master
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$ git reset --hard ceph/master
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Finally, the ``master`` branch of your fork can then be synced to upstream
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master by::
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$ git push -u origin master
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Bugfix branch
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-------------
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Next, create a branch for the bugfix:
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.. code::
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$ git checkout master
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$ git checkout -b fix_1
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$ git push -u origin fix_1
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This creates a ``fix_1`` branch locally and in our GitHub fork. At this
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point, the ``fix_1`` branch is identical to the ``master`` branch, but not
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for long! You are now ready to modify the code.
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Fix bug locally
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---------------
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At this point, change the status of the tracker issue to "In progress" to
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communicate to the other Ceph developers that you have begun working on a
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fix. If you don't have permission to change that field, your comment that
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you are working on the issue is sufficient.
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Possibly, your fix is very simple and requires only minimal testing.
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More likely, it will be an iterative process involving trial and error, not
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to mention skill. An explanation of how to fix bugs is beyond the
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scope of this document. Instead, we focus on the mechanics of the process
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in the context of the Ceph project.
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A detailed discussion of the tools available for validating your bugfixes,
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see the `Testing`_ chapter.
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For now, let us just assume that you have finished work on the bugfix and
|
|
that you have tested it and believe it works. Commit the changes to your local
|
|
branch using the ``--signoff`` option::
|
|
|
|
$ git commit -as
|
|
|
|
and push the changes to your fork::
|
|
|
|
$ git push origin fix_1
|
|
|
|
GitHub pull request
|
|
-------------------
|
|
|
|
The next step is to open a GitHub pull request. The purpose of this step is
|
|
to make your bugfix available to the community of Ceph developers. They
|
|
will review it and may do additional testing on it.
|
|
|
|
In short, this is the point where you "go public" with your modifications.
|
|
Psychologically, you should be prepared to receive suggestions and
|
|
constructive criticism. Don't worry! In our experience, the Ceph project is
|
|
a friendly place!
|
|
|
|
If you are uncertain how to use pull requests, you may read
|
|
`this GitHub pull request tutorial`_.
|
|
|
|
.. _`this GitHub pull request tutorial`:
|
|
https://help.github.com/articles/using-pull-requests/
|
|
|
|
For some ideas on what constitutes a "good" pull request, see
|
|
the `Git Commit Good Practice`_ article at the `OpenStack Project Wiki`_.
|
|
|
|
.. _`Git Commit Good Practice`: https://wiki.openstack.org/wiki/GitCommitMessages
|
|
.. _`OpenStack Project Wiki`: https://wiki.openstack.org/wiki/Main_Page
|
|
|
|
Once your pull request (PR) is opened, update the `Issue tracker`_ by
|
|
adding a comment to the bug pointing the other developers to your PR. The
|
|
update can be as simple as::
|
|
|
|
*PR*: https://github.com/ceph/ceph/pull/$NUMBER_OF_YOUR_PULL_REQUEST
|
|
|
|
Automated PR validation
|
|
-----------------------
|
|
|
|
When your PR hits GitHub, the Ceph project's `Continuous Integration (CI)
|
|
<https://en.wikipedia.org/wiki/Continuous_integration>`_
|
|
infrastructure will test it automatically. At the time of this writing
|
|
(March 2016), the automated CI testing included a test to check that the
|
|
commits in the PR are properly signed (see `Submitting patches`_) and a
|
|
``make check`` test.
|
|
|
|
The latter, ``make check``, builds the PR and runs it through a battery of
|
|
tests. These tests run on machines operated by the Ceph Continuous
|
|
Integration (CI) team. When the tests complete, the result will be shown
|
|
on GitHub in the pull request itself.
|
|
|
|
You can (and should) also test your modifications before you open a PR.
|
|
Refer to the the `Testing`_ chapter for details.
|
|
|
|
Integration tests AKA ceph-qa-suite
|
|
-----------------------------------
|
|
|
|
Since Ceph is a complex beast, it may also be necessary to test your fix to
|
|
see how it behaves on real clusters running either on real or virtual
|
|
hardware. Tests designed for this purpose live in the `ceph-qa-suite
|
|
repository`_ and are run via the `teuthology framework`_.
|
|
|
|
.. _`ceph-qa-suite repository`: https://github.com/ceph/ceph-qa-suite/
|
|
.. _`teuthology repository`: https://github.com/ceph/teuthology
|
|
.. _`teuthology framework`: https://github.com/ceph/teuthology
|
|
|
|
If you have access to an OpenStack tenant, you are encouraged to run the
|
|
integration tests yourself using `ceph-workbench ceph-qa-suite`_,
|
|
and to post the test results to the PR.
|
|
|
|
.. _`ceph-workbench ceph-qa-suite`: http://ceph-workbench.readthedocs.org/
|
|
|
|
The Ceph community has access to the `Sepia lab
|
|
<http://ceph.github.io/sepia/>`_ where integration tests can be run on
|
|
real hardware. Other developers may add tags like "needs-qa" to your PR.
|
|
This allows PRs that need testing to be merged into a single branch and
|
|
tested all at the same time. Since teuthology suites can take hours
|
|
(even days in some cases) to run, this can save a lot of time.
|
|
|
|
Integration testing is discussed in more detail in the `Testing`_ chapter.
|
|
|
|
Code review
|
|
-----------
|
|
|
|
Once your bugfix has been thoroughly tested, or even during this process,
|
|
it will be subjected to code review by other developers. This typically
|
|
takes the form of correspondence in the PR itself, but can be supplemented
|
|
by discussions on `IRC`_ and the `Mailing list`_.
|
|
|
|
Amending your PR
|
|
----------------
|
|
|
|
While your PR is going through `Testing`_ and `Code review`_, you can
|
|
modify it at any time by editing files in your local branch.
|
|
|
|
After the changes are committed locally (to the ``fix_1`` branch in our
|
|
example), they need to be pushed to GitHub so they appear in the PR.
|
|
|
|
Modifying the PR is done by adding commits to the ``fix_1`` branch upon
|
|
which it is based, often followed by rebasing to modify the branch's git
|
|
history. See `this tutorial
|
|
<https://www.atlassian.com/git/tutorials/rewriting-history>`_ for a good
|
|
introduction to rebasing. When you are done with your modifications, you
|
|
will need to force push your branch with:
|
|
|
|
.. code::
|
|
|
|
$ git push --force origin fix_1
|
|
|
|
Merge
|
|
-----
|
|
|
|
The bugfixing process culminates when one of the project leads decides to
|
|
merge your PR.
|
|
|
|
When this happens, it is a signal for you (or the lead who merged the PR)
|
|
to change the `Issue tracker`_ status to "Resolved". Some issues may be
|
|
flagged for backporting, in which case the status should be changed to
|
|
"Pending Backport" (see the `Backporting`_ chapter for details).
|
|
|
|
|
|
Testing
|
|
=======
|
|
|
|
Ceph has two types of tests: "make check" tests and integration tests.
|
|
The former are run via `GNU Make <https://www.gnu.org/software/make/>`,
|
|
and the latter are run via the `teuthology framework`_. The following two
|
|
chapters examine the "make check" and integration tests in detail.
|
|
|
|
Testing - make check
|
|
====================
|
|
|
|
After compiling Ceph, the ``make check`` command can be used to run the
|
|
code through a battery of tests covering various aspects of Ceph. For
|
|
inclusion in "make check", a test must:
|
|
|
|
* bind ports that do not conflict with other tests
|
|
* not require root access
|
|
* not require more than one machine to run
|
|
* complete within a few minutes
|
|
|
|
While it is possible to run ``make check`` directly, it can be tricky to
|
|
correctly set up your environment. Fortunately, a script is provided to
|
|
make it easier run "make check" on your code. It can be run from the
|
|
top-level directory of the Ceph source tree by doing::
|
|
|
|
$ ./run-make-check.sh
|
|
|
|
You will need a minimum of 8GB of RAM and 32GB of free disk space for this
|
|
command to complete successfully on x86_64 (other architectures may have
|
|
different constraints). Depending on your hardware, it can take from 20
|
|
minutes to three hours to complete, but it's worth the wait.
|
|
|
|
Future sections
|
|
---------------
|
|
|
|
* Principles of make check tests
|
|
* Where to find test results
|
|
* How to interpret test results
|
|
* Find the corresponding source code
|
|
* Writing make check tests
|
|
* Make check caveats
|
|
|
|
Testing - integration tests
|
|
===========================
|
|
|
|
When a test requires multiple machines, root access or lasts for a
|
|
longer time (for example, to simulate a realistic Ceph deployment), it
|
|
is deemed to be an integration test. Integration tests are organized into
|
|
"suites", which are defined in the `ceph-qa-suite repository`_ and run with
|
|
the ``teuthology-suite`` command.
|
|
|
|
The ``teuthology-suite`` command is part of the `teuthology framework`_.
|
|
In the sections that follow we attempt to provide a detailed introduction
|
|
to that framework from the perspective of a beginning Ceph developer.
|
|
|
|
Teuthology consumes packages
|
|
----------------------------
|
|
|
|
It may take some time to understand the significance of this fact, but it
|
|
is `very` significant. It means that automated tests can be conducted on
|
|
multiple platforms using the same packages (RPM, DEB) that can be
|
|
installed on any machine running those platforms.
|
|
|
|
Teuthology has a `list of platforms that it supports
|
|
<https://github.com/ceph/ceph-qa-suite/tree/master/distros/supported>`_ (as
|
|
of March 2016 the list consisted of "CentOS 7.2" and "Ubuntu 14.04"). It
|
|
expects to be provided pre-built Ceph packages for these platforms.
|
|
Teuthology deploys these platforms on machines (bare-metal or
|
|
cloud-provisioned), installs the packages on them, and deploys Ceph
|
|
clusters on them - all as called for by the test.
|
|
|
|
The nightlies
|
|
-------------
|
|
|
|
A number of integration tests are run on a regular basis in the `Sepia
|
|
lab`_ against the official Ceph repositories (on the ``master`` development
|
|
branch and the stable branches). Traditionally, these tests are called "the
|
|
nightlies" because the Ceph core developers used to live and work in
|
|
the same time zone and from their perspective the tests were run overnight.
|
|
|
|
The results of the nightlies are published at http://pulpito.ceph.com/ and
|
|
http://pulpito.ovh.sepia.ceph.com:8081/. The developer nick shows in the
|
|
test results URL and in the first column of the Pulpito dashboard. The
|
|
results are also reported on the `ceph-qa mailing list
|
|
<http://ceph.com/resources/mailing-list-irc/>`_ for analysis.
|
|
|
|
Suites inventory
|
|
----------------
|
|
|
|
The ``suites`` directory of the `ceph-qa-suite repository`_ contains
|
|
all the integration tests, for all the Ceph components.
|
|
|
|
`ceph-deploy <https://github.com/ceph/ceph-qa-suite/tree/master/suites/ceph-deploy>`_
|
|
install a Ceph cluster with ``ceph-deploy`` (`ceph-deploy man page`_)
|
|
|
|
`ceph-disk <https://github.com/ceph/ceph-qa-suite/tree/master/suites/ceph-disk>`_
|
|
verify init scripts (upstart etc.) and udev integration with
|
|
``ceph-disk`` (`ceph-disk man page`_), with and without `dmcrypt
|
|
<https://gitlab.com/cryptsetup/cryptsetup/wikis/DMCrypt>`_ support.
|
|
|
|
`dummy <https://github.com/ceph/ceph-qa-suite/tree/master/suites/dummy>`_
|
|
get a machine, do nothing and return success (commonly used to
|
|
verify the integration testing infrastructure works as expected)
|
|
|
|
`fs <https://github.com/ceph/ceph-qa-suite/tree/master/suites/fs>`_
|
|
test CephFS
|
|
|
|
`kcephfs <https://github.com/ceph/ceph-qa-suite/tree/master/suites/kcephfs>`_
|
|
test the CephFS kernel module
|
|
|
|
`krbd <https://github.com/ceph/ceph-qa-suite/tree/master/suites/krbd>`_
|
|
test the RBD kernel module
|
|
|
|
`powercycle <https://github.com/ceph/ceph-qa-suite/tree/master/suites/powercycle>`_
|
|
verify the Ceph cluster behaves when machines are powered off
|
|
and on again
|
|
|
|
`rados <https://github.com/ceph/ceph-qa-suite/tree/master/suites/rados>`_
|
|
run Ceph clusters including OSDs and MONs, under various conditions of
|
|
stress
|
|
|
|
`rbd <https://github.com/ceph/ceph-qa-suite/tree/master/suites/rbd>`_
|
|
run RBD tests using actual Ceph clusters, with and without qemu
|
|
|
|
`rgw <https://github.com/ceph/ceph-qa-suite/tree/master/suites/rgw>`_
|
|
run RGW tests using actual Ceph clusters
|
|
|
|
`smoke <https://github.com/ceph/ceph-qa-suite/tree/master/suites/smoke>`_
|
|
run tests that exercise the Ceph API with an actual Ceph cluster
|
|
|
|
`teuthology <https://github.com/ceph/ceph-qa-suite/tree/master/suites/teuthology>`_
|
|
verify that teuthology can run integration tests, with and without OpenStack
|
|
|
|
`upgrade <https://github.com/ceph/ceph-qa-suite/tree/master/suites/upgrade>`_
|
|
for various versions of Ceph, verify that upgrades can happen
|
|
without disrupting an ongoing workload
|
|
|
|
.. _`ceph-deploy man page`: ../../man/8/ceph-deploy
|
|
.. _`ceph-disk man page`: ../../man/8/ceph-disk
|
|
|
|
teuthology-describe-tests
|
|
-------------------------
|
|
|
|
In February 2016, a new feature called ``teuthology-describe-tests`` was
|
|
added to the `teuthology framework`_ to facilitate documentation and better
|
|
understanding of integration tests (`feature announcement
|
|
<http://article.gmane.org/gmane.comp.file-systems.ceph.devel/29287>`_).
|
|
|
|
The upshot is that tests can be documented by embedding ``meta:``
|
|
annotations in the yaml files used to define the tests. The results can be
|
|
seen in the `ceph-qa-suite wiki
|
|
<http://tracker.ceph.com/projects/ceph-qa-suite/wiki/>`_.
|
|
|
|
Since this is a new feature, many yaml files have yet to be annotated.
|
|
Developers are encouraged to improve the documentation, in terms of both
|
|
coverage and quality.
|
|
|
|
How integration tests are run
|
|
-----------------------------
|
|
|
|
Given that - as a new Ceph developer - you will typically not have access
|
|
to the `Sepia lab`_, you may rightly ask how you can run the integration
|
|
tests in your own environment.
|
|
|
|
One option is to set up a teuthology cluster on bare metal. Though this is
|
|
a non-trivial task, it `is` possible. Here are `some notes
|
|
<http://docs.ceph.com/teuthology/docs/LAB_SETUP.html>`_ to get you started
|
|
if you decide to go this route.
|
|
|
|
If you have access to an OpenStack tenant, you have another option: the
|
|
`teuthology framework`_ has an OpenStack backend, which is documented `here
|
|
<https://github.com/dachary/teuthology/tree/openstack#openstack-backend>`_.
|
|
This OpenStack backend can build packages from a given git commit or
|
|
branch, provision VMs, install the packages and run integration tests
|
|
on those VMs. This process is controlled using a tool called
|
|
`ceph-workbench ceph-qa-suite`_. This tool also automates publishing of
|
|
test results at http://teuthology-logs.public.ceph.com.
|
|
|
|
Running integration tests on your code contributions and publishing the
|
|
results allows reviewers to verify that changes to the code base do not
|
|
cause regressions, or to analyze test failures when they do occur.
|
|
|
|
Every teuthology cluster, whether bare-metal or cloud-provisioned, has a
|
|
so-called "teuthology machine" from which tests suites are triggered using the
|
|
``teuthology-suite`` command.
|
|
|
|
A detailed and up-to-date description of each `teuthology-suite`_ option is
|
|
available by running the following command on the teuthology machine::
|
|
|
|
$ teuthology-suite --help
|
|
|
|
How integration tests are defined
|
|
---------------------------------
|
|
|
|
Integration tests are defined by yaml files found in the ``suites``
|
|
subdirectory of the `ceph-qa-suite repository`_ and implemented by python
|
|
code found in the ``tasks`` subdirectory. Some tests ("standalone tests")
|
|
are defined in a single yaml file, while other tests are defined by a
|
|
directory tree containing yaml files that are combined, at runtime, into a
|
|
larger yaml file.
|
|
|
|
Reading a standalone test
|
|
-------------------------
|
|
|
|
Let us first examine a standalone test, or "singleton".
|
|
|
|
Here is a commented example using the integration test
|
|
`rados/singleton/all/admin-socket.yaml
|
|
<https://github.com/ceph/ceph-qa-suite/blob/master/suites/rados/singleton/all/admin-socket.yaml>`_
|
|
::
|
|
|
|
roles:
|
|
- - mon.a
|
|
- osd.0
|
|
- osd.1
|
|
tasks:
|
|
- install:
|
|
- ceph:
|
|
- admin_socket:
|
|
osd.0:
|
|
version:
|
|
git_version:
|
|
help:
|
|
config show:
|
|
config set filestore_dump_file /tmp/foo:
|
|
perf dump:
|
|
perf schema:
|
|
|
|
The ``roles`` array determines the composition of the cluster (how
|
|
many MONs, OSDs, etc.) on which this test is designed to run, as well
|
|
as how these roles will be distributed over the machines in the
|
|
testing cluster. In this case, there is only one element in the
|
|
top-level array: therefore, only one machine is allocated to the
|
|
test. The nested array declares that this machine shall run a MON with
|
|
id ``a`` (that is the ``mon.a`` in the list of roles) and two OSDs
|
|
(``osd.0`` and ``osd.1``).
|
|
|
|
The body of the test is in the ``tasks`` array: each element is
|
|
evaluated in order, causing the corresponding python file found in the
|
|
``tasks`` subdirectory of the `teuthology repository`_ or
|
|
`ceph-qa-suite repository`_ to be run. "Running" in this case means calling
|
|
the ``task()`` function defined in that file.
|
|
|
|
In this case, the `install
|
|
<https://github.com/ceph/teuthology/blob/master/teuthology/task/install.py>`_
|
|
task comes first. It installs the Ceph packages on each machine (as
|
|
defined by the ``roles`` array). A full description of the ``install``
|
|
task is `found in the python file
|
|
<https://github.com/ceph/teuthology/blob/master/teuthology/task/install.py>`_
|
|
(search for "def task").
|
|
|
|
The ``ceph`` task, which is documented `here
|
|
<https://github.com/ceph/ceph-qa-suite/blob/master/tasks/ceph.py>`_ (again,
|
|
search for "def task"), starts OSDs and MONs (and possibly MDSs as well)
|
|
as required by the ``roles`` array. In this example, it will start one MON
|
|
(``mon.a``) and two OSDs (``osd.0`` and ``osd.1``), all on the same
|
|
machine. Control moves to the next task when the Ceph cluster reaches
|
|
``HEALTH_OK`` state.
|
|
|
|
The next task is ``admin_socket`` (`source code
|
|
<https://github.com/ceph/ceph-qa-suite/blob/master/tasks/admin_socket.py>`_).
|
|
The parameter of the ``admin_socket`` task (and any other task) is a
|
|
structure which is interpreted as documented in the task. In this example
|
|
the parameter is a set of commands to be sent to the admin socket of
|
|
``osd.0``. The task verifies that each of them returns on success (i.e.
|
|
exit code zero).
|
|
|
|
This test can be run with::
|
|
|
|
$ teuthology-suite --suite rados/singleton/all/admin-socket.yaml fs/ext4.yaml
|
|
|
|
Test descriptions
|
|
-----------------
|
|
|
|
Each test has a "test description", which is similar to a directory path,
|
|
but not the same. In the case of a standalone test, like the one in
|
|
`Reading a standalone test`_, the test description is identical to the
|
|
relative path (starting from the ``suites/`` directory of the
|
|
`ceph-qa-suite repository`_) of the yaml file defining the test.
|
|
|
|
Much more commonly, tests are defined not by a single yaml file, but by a
|
|
`directory tree of yaml files`. At runtime, the tree is walked and all yaml
|
|
files (facets) are combined into larger yaml "programs" that define the
|
|
tests. A full listing of the yaml defining the test is included at the
|
|
beginning of every test log.
|
|
|
|
In these cases, the description of each test consists of the
|
|
subdirectory under `suites/
|
|
<https://github.com/ceph/ceph-qa-suite/tree/master/suites>`_ containing the
|
|
yaml facets, followed by an expression in curly braces (``{}``) consisting of
|
|
a list of yaml facets in order of concatenation. For instance the
|
|
test description::
|
|
|
|
ceph-disk/basic/{distros/centos_7.0.yaml tasks/ceph-disk.yaml}
|
|
|
|
signifies the concatenation of two files:
|
|
|
|
* ceph-disk/basic/distros/centos_7.0.yaml
|
|
* ceph-disk/basic/tasks/ceph-disk.yaml
|
|
|
|
How are tests built from directories?
|
|
-------------------------------------
|
|
|
|
As noted in the previous section, most tests are not defined in a single
|
|
yaml file, but rather as a `combination` of files collected from a
|
|
directory tree within the ``suites/`` subdirectory of the `ceph-qa-suite repository`_.
|
|
|
|
The set of all tests defined by a given subdirectory of ``suites/`` is
|
|
called an "integration test suite", or a "teuthology suite".
|
|
|
|
Combination of yaml facets is controlled by special files (``%`` and
|
|
``+``) that are placed within the directory tree and can be thought of as
|
|
operators. The ``%`` file is the "convolution" operator and ``+``
|
|
signifies concatenation.
|
|
|
|
Convolution operator
|
|
--------------------
|
|
|
|
The convolution operator, implemented as an empty file called ``%``, tells
|
|
teuthology to construct a test matrix from yaml facets found in
|
|
subdirectories below the directory containing the operator.
|
|
|
|
For example, the `ceph-disk suite
|
|
<https://github.com/ceph/ceph-qa-suite/tree/jewel/suites/ceph-disk/>`_ is
|
|
defined by the ``suites/ceph-disk/`` tree, which consists of the files and
|
|
subdirectories in the following structure::
|
|
|
|
directory: ceph-disk/basic
|
|
file: %
|
|
directory: distros
|
|
file: centos_7.0.yaml
|
|
file: ubuntu_14.04.yaml
|
|
directory: tasks
|
|
file: ceph-disk.yaml
|
|
|
|
This is interpreted as a 2x1 matrix consisting of two tests:
|
|
|
|
1. ceph-disk/basic/{distros/centos_7.0.yaml tasks/ceph-disk.yaml}
|
|
2. ceph-disk/basic/{distros/ubuntu_14.04.yaml tasks/ceph-disk.yaml}
|
|
|
|
i.e. the concatenation of centos_7.0.yaml and ceph-disk.yaml and
|
|
the concatenation of ubuntu_14.04.yaml and ceph-disk.yaml, respectively.
|
|
In human terms, this means that the task found in ``ceph-disk.yaml`` is
|
|
intended to run on both CentOS 7.0 and Ubuntu 14.04.
|
|
|
|
Without the file percent, the ``ceph-disk`` tree would be interpreted as
|
|
three standalone tests:
|
|
|
|
* ceph-disk/basic/distros/centos_7.0.yaml
|
|
* ceph-disk/basic/distros/ubuntu_14.04.yaml
|
|
* ceph-disk/basic/tasks/ceph-disk.yaml
|
|
|
|
(which would of course be wrong in this case).
|
|
|
|
Referring to the `ceph-qa-suite repository`_, you will notice that the
|
|
``centos_7.0.yaml`` and ``ubuntu_14.04.yaml`` files in the
|
|
``suites/ceph-disk/basic/distros/`` directory are implemented as symlinks.
|
|
By using symlinks instead of copying, a single file can appear in multiple
|
|
suites. This eases the maintenance of the test framework as a whole.
|
|
|
|
All the tests generated from the ``suites/ceph-disk/`` directory tree
|
|
(also known as the "ceph-disk suite") can be run with::
|
|
|
|
$ teuthology-suite --suite ceph-disk
|
|
|
|
An individual test from the `ceph-disk suite`_ can be run by adding the
|
|
``--filter`` option::
|
|
|
|
$ teuthology-suite \
|
|
--suite ceph-disk/basic \
|
|
--filter 'ceph-disk/basic/{distros/ubuntu_14.04.yaml tasks/ceph-disk.yaml}'
|
|
|
|
.. note: To run a standalone test like the one in `Reading a standalone
|
|
test`_, ``--suite`` alone is sufficient. If you want to run a single
|
|
test from a suite that is defined as a directory tree, ``--suite`` must
|
|
be combined with ``--filter``. This is because the ``--suite`` option
|
|
understands POSIX relative paths only.
|
|
|
|
Concatenation operator
|
|
----------------------
|
|
|
|
For even greater flexibility in sharing yaml files between suites, the
|
|
special file plus (``+``) can be used to concatenate files within a
|
|
directory. For instance, consider the `suites/rbd/thrash
|
|
<https://github.com/ceph/ceph-qa-suite/tree/master/suites/rbd/thrash>`_
|
|
tree::
|
|
|
|
directory: rbd/thrash
|
|
file: %
|
|
directory: clusters
|
|
file: +
|
|
file: fixed-2.yaml
|
|
file: openstack.yaml
|
|
directory: workloads
|
|
file: rbd_api_tests_copy_on_read.yaml
|
|
file: rbd_api_tests.yaml
|
|
|
|
This creates two tests:
|
|
|
|
* rbd/thrash/{clusters/fixed-2.yaml clusters/openstack.yaml workloads/rbd_api_tests_copy_on_read.yaml}
|
|
* rbd/thrash/{clusters/fixed-2.yaml clusters/openstack.yaml workloads/rbd_api_tests.yaml}
|
|
|
|
Because the ``clusters/`` subdirectory contains the special file plus
|
|
(``+``), all the other files in that subdirectory (``fixed-2.yaml`` and
|
|
``openstack.yaml`` in this case) are concatenated together
|
|
and treated as a single file. Without the special file plus, they would
|
|
have been convolved with the files from the workloads directory to create
|
|
a 2x2 matrix:
|
|
|
|
* rbd/thrash/{clusters/openstack.yaml workloads/rbd_api_tests_copy_on_read.yaml}
|
|
* rbd/thrash/{clusters/openstack.yaml workloads/rbd_api_tests.yaml}
|
|
* rbd/thrash/{clusters/fixed-2.yaml workloads/rbd_api_tests_copy_on_read.yaml}
|
|
* rbd/thrash/{clusters/fixed-2.yaml workloads/rbd_api_tests.yaml}
|
|
|
|
The ``clusters/fixed-2.yaml`` file is shared among many suites to
|
|
define the following ``roles``::
|
|
|
|
roles:
|
|
- [mon.a, mon.c, osd.0, osd.1, osd.2, client.0]
|
|
- [mon.b, osd.3, osd.4, osd.5, client.1]
|
|
|
|
The ``rbd/thrash`` suite as defined above, consisting of two tests,
|
|
can be run with::
|
|
|
|
$ teuthology-suite --suite rbd/thrash
|
|
|
|
A single test from the rbd/thrash suite can be run by adding the
|
|
``--filter`` option::
|
|
|
|
$ teuthology-suite \
|
|
--suite rbd/thrash \
|
|
--filter 'rbd/thrash/{clusters/fixed-2.yaml clusters/openstack.yaml workloads/rbd_api_tests_copy_on_read.yaml}'
|
|
|
|
Filtering tests by their description
|
|
------------------------------------
|
|
|
|
When a few jobs fail and need to be run again, the ``--filter`` option
|
|
can be used to select tests with a matching description. For instance, if the
|
|
``rados`` suite fails the `all/peer.yaml <https://github.com/ceph/ceph-qa-suite/blob/master/suites/rados/singleton/all/peer.yaml>`_ test, the following will only run the tests that contain this file::
|
|
|
|
teuthology-suite --suite rados --filter all/peer.yaml
|
|
|
|
The ``--filter-out`` option does the opposite (it matches tests that do
|
|
`not` contain a given string), and can be combined with the ``--filter``
|
|
option.
|
|
|
|
Both ``--filter`` and ``--filter-out`` take a comma-separated list of strings (which
|
|
means the comma character is implicitly forbidden in filenames found in the
|
|
`ceph-qa-suite repository`_). For instance::
|
|
|
|
teuthology-suite --suite rados --filter all/peer.yaml,all/rest-api.yaml
|
|
|
|
will run tests that contain either
|
|
`all/peer.yaml <https://github.com/ceph/ceph-qa-suite/blob/master/suites/rados/singleton/all/peer.yaml>`_
|
|
or
|
|
`all/rest-api.yaml <https://github.com/ceph/ceph-qa-suite/blob/master/suites/rados/singleton/all/rest-api.yaml>`_
|
|
|
|
Each string is looked up anywhere in the test description and has to
|
|
be an exact match: they are not regular expressions.
|
|
|
|
Reducing the number of tests
|
|
----------------------------
|
|
|
|
The ``rados`` suite generates thousands of tests out of a few hundred
|
|
files. For instance, all tests in the `rados/thrash suite
|
|
<https://github.com/ceph/ceph-qa-suite/tree/master/suites/rados/thrash>`_
|
|
run for ``xfs``, ``btrfs`` and ``ext4`` because they are combined (via
|
|
special file ``%``) with the `fs directory
|
|
<https://github.com/ceph/ceph-qa-suite/tree/master/suites/rados/thrash/fs>`_
|
|
|
|
All integration tests are required to be run before a Ceph release is published.
|
|
When merely verifying whether a contribution can be merged without
|
|
risking a trivial regression, it is enough to run a subset. The ``--subset`` option can be used to
|
|
reduce the number of tests that are triggered. For instance::
|
|
|
|
teuthology-suite --suite rados --subset 0/4000
|
|
|
|
will run as few tests as possible. The tradeoff in this case is that
|
|
some tests will only run on ``xfs`` and not on ``ext4`` or ``btrfs``,
|
|
but no matter how small a ratio is provided in the ``--subset``,
|
|
teuthology will still ensure that all files in the suite are in at
|
|
least one test. Understanding the actual logic that drives this
|
|
requires reading the teuthology source code.
|
|
|
|
The ``--limit`` option only runs the first ``N`` tests in the suite:
|
|
this is rarely useful, however, because there is no way to control which
|
|
test will be first.
|
|
|
|
Testing in the cloud
|
|
====================
|
|
|
|
In this chapter, we will explain in detail how use an OpenStack
|
|
tenant as an environment for Ceph integration testing.
|
|
|
|
Assumptions and caveat
|
|
----------------------
|
|
|
|
We assume that:
|
|
|
|
1. you are the only person using the tenant
|
|
2. you have the credentials
|
|
3. the tenant supports the ``nova`` and ``cinder`` APIs
|
|
|
|
Caveat: be aware that, as of this writing (July 2016), testing in
|
|
OpenStack clouds is a new feature. Things may not work as advertised.
|
|
If you run into trouble, ask for help on `IRC`_ or the `Mailing list`_, or
|
|
open a bug report at the `ceph-workbench bug tracker`_.
|
|
|
|
.. _`ceph-workbench bug tracker`: http://ceph-workbench.dachary.org/root/ceph-workbench/issues
|
|
|
|
Prepare tenant
|
|
--------------
|
|
|
|
If you have not tried to use ``ceph-workbench`` with this tenant before,
|
|
proceed to the next step.
|
|
|
|
To start with a clean slate, login to your tenant via the Horizon dashboard and:
|
|
|
|
* terminate the ``teuthology`` and ``packages-repository`` instances, if any
|
|
* delete the ``teuthology`` security group
|
|
* delete the ``teuthology`` and ``teuthology-myself`` key pairs
|
|
|
|
Also do the above if you ever get key-related errors ("invalid key", etc.) when
|
|
trying to schedule suites.
|
|
|
|
Getting ceph-workbench
|
|
----------------------
|
|
|
|
Since testing in the cloud is done using the `ceph-workbench
|
|
ceph-qa-suite`_ tool, you will need to install that first. It is designed
|
|
to be installed via Docker, so if you don't have Docker running on your
|
|
development machine, take care of that first. The Docker project has a good
|
|
tutorial called `Get Started with Docker Engine for Linux
|
|
<https://docs.docker.com/linux/>`_ if you unsure how to proceed.
|
|
|
|
Once Docker is up and running, install ``ceph-workbench`` by following the
|
|
`Installation instructions in the ceph-workbench documentation
|
|
<http://ceph-workbench.readthedocs.org/en/latest/#installation>`_::
|
|
|
|
Linking ceph-workbench with your OpenStack tenant
|
|
-------------------------------------------------
|
|
|
|
Before you can trigger your first teuthology suite, you will need to link
|
|
``ceph-workbench`` with your OpenStack account.
|
|
|
|
First, download a ``openrc.sh`` file by clicking on the "Download OpenStack
|
|
RC File" button, which can be found in the "API Access" tab of the "Access
|
|
& Security" dialog of the OpenStack Horizon dashboard.
|
|
|
|
Second, create a ``~/.ceph-workbench`` directory, set its permissions to
|
|
700, and move the ``openrc.sh`` file into it. Make sure that the filename
|
|
is exactly ``~/.ceph-workbench/openrc.sh``.
|
|
|
|
Third, edit the file so it does not ask for your OpenStack password
|
|
interactively. Comment out the relevant lines and replace them with
|
|
something like::
|
|
|
|
export OS_PASSWORD="aiVeth0aejee3eep8rogho3eep7Pha6ek"
|
|
|
|
When `ceph-workbench ceph-qa-suite`_ connects to your OpenStack tenant for
|
|
the first time, it will generate two keypairs: ``teuthology-myself`` and
|
|
``teuthology``.
|
|
|
|
.. If this is not the first time you have tried to use
|
|
.. `ceph-workbench ceph-qa-suite`_ with this tenant, make sure to delete any
|
|
.. stale keypairs with these names!
|
|
|
|
Run the dummy suite
|
|
-------------------
|
|
|
|
You are now ready to take your OpenStack teuthology setup for a test
|
|
drive::
|
|
|
|
$ ceph-workbench ceph-qa-suite --suite dummy
|
|
|
|
Be forewarned that the first run of `ceph-workbench ceph-qa-suite`_ on a
|
|
pristine tenant will take a long time to complete because it downloads a VM
|
|
image and during this time the command may not produce any output.
|
|
|
|
The images are cached in OpenStack, so they are only downloaded once.
|
|
Subsequent runs of the same command will complete faster.
|
|
|
|
Although ``dummy`` suite does not run any tests, in all other respects it
|
|
behaves just like a teuthology suite and produces some of the same
|
|
artifacts.
|
|
|
|
The last bit of output should look something like this::
|
|
|
|
pulpito web interface: http://149.202.168.201:8081/
|
|
ssh access : ssh -i /home/smithfarm/.ceph-workbench/teuthology-myself.pem ubuntu@149.202.168.201 # logs in /usr/share/nginx/html
|
|
|
|
What this means is that `ceph-workbench ceph-qa-suite`_ triggered the test
|
|
suite run. It does not mean that the suite run has completed. To monitor
|
|
progress of the run, check the Pulpito web interface URL periodically, or
|
|
if you are impatient, ssh to the teuthology machine using the ssh command
|
|
shown and do::
|
|
|
|
$ tail -f /var/log/teuthology.*
|
|
|
|
The `/usr/share/nginx/html` directory contains the complete logs of the
|
|
test suite. If we had provided the ``--upload`` option to the
|
|
`ceph-workbench ceph-qa-suite`_ command, these logs would have been
|
|
uploaded to http://teuthology-logs.public.ceph.com.
|
|
|
|
Run a standalone test
|
|
---------------------
|
|
|
|
The standalone test explained in `Reading a standalone test`_ can be run
|
|
with the following command::
|
|
|
|
$ ceph-workbench ceph-qa-suite --suite rados/singleton/all/admin-socket.yaml
|
|
|
|
This will run the suite shown on the current ``master`` branch of
|
|
``ceph/ceph.git``. You can specify a different branch with the ``--ceph``
|
|
option, and even a different git repo with the ``--ceph-git-url`` option. (Run
|
|
``ceph-workbench ceph-qa-suite --help`` for an up-to-date list of available
|
|
options.)
|
|
|
|
The first run of a suite will also take a long time, because ceph packages
|
|
have to be built, first. Again, the packages so built are cached and
|
|
`ceph-workbench ceph-qa-suite`_ will not build identical packages a second
|
|
time.
|
|
|
|
Interrupt a running suite
|
|
-------------------------
|
|
|
|
Teuthology suites take time to run. From time to time one may wish to
|
|
interrupt a running suite. One obvious way to do this is::
|
|
|
|
ceph-workbench ceph-qa-suite --teardown
|
|
|
|
This destroys all VMs created by `ceph-workbench ceph-qa-suite`_ and
|
|
returns the OpenStack tenant to a "clean slate".
|
|
|
|
Sometimes you may wish to interrupt the running suite, but keep the logs,
|
|
the teuthology VM, the packages-repository VM, etc. To do this, you can
|
|
``ssh`` to the teuthology VM (using the ``ssh access`` command reported
|
|
when you triggered the suite -- see `Run the dummy suite`_) and, once
|
|
there::
|
|
|
|
sudo /etc/init.d/teuthology restart
|
|
|
|
This will keep the teuthology machine, the logs and the packages-repository
|
|
instance but nuke everything else.
|
|
|
|
Upload logs to archive server
|
|
-----------------------------
|
|
|
|
Since the teuthology instance in OpenStack is only semi-permanent, with limited
|
|
space for storing logs, ``teuthology-openstack`` provides an ``--upload``
|
|
option which, if included in the ``ceph-workbench ceph-qa-suite`` command,
|
|
will cause logs from all failed jobs to be uploaded to the log archive server
|
|
maintained by the Ceph project. The logs will appear at the URL::
|
|
|
|
http://teuthology-logs.public.ceph.com/$RUN
|
|
|
|
where ``$RUN`` is the name of the run. It will be a string like this::
|
|
|
|
ubuntu-2016-07-23_16:08:12-rados-hammer-backports---basic-openstack
|
|
|
|
Even if you don't providing the ``--upload`` option, however, all the logs can
|
|
still be found on the teuthology machine in the directory
|
|
``/usr/share/nginx/html``.
|
|
|
|
Provision VMs ad hoc
|
|
--------------------
|
|
|
|
From the teuthology VM, it is possible to provision machines on an "ad hoc"
|
|
basis, to use however you like. The magic incantation is::
|
|
|
|
teuthology-lock --lock-many $NUMBER_OF_MACHINES \
|
|
--os-type $OPERATING_SYSTEM \
|
|
--os-version $OS_VERSION \
|
|
--machine-type openstack \
|
|
--owner $EMAIL_ADDRESS
|
|
|
|
The command must be issued from the ``~/teuthology`` directory. The possible
|
|
values for ``OPERATING_SYSTEM`` AND ``OS_VERSION`` can be found by examining
|
|
the contents of the directory ``teuthology/openstack/``. For example::
|
|
|
|
teuthology-lock --lock-many 1 --os-type ubuntu --os-version 16.04 \
|
|
--machine-type openstack --owner foo@example.com
|
|
|
|
When you are finished with the machine, find it in the list of machines::
|
|
|
|
openstack server list
|
|
|
|
to determine the name or ID, and then terminate it with::
|
|
|
|
openstack server delete $NAME_OR_ID
|
|
|
|
Deploy a cluster for manual testing
|
|
-----------------------------------
|
|
|
|
The `teuthology framework`_ and `ceph-workbench ceph-qa-suite`_ are
|
|
versatile tools that automatically provision Ceph clusters in the cloud and
|
|
run various tests on them in an automated fashion. This enables a single
|
|
engineer, in a matter of hours, to perform thousands of tests that would
|
|
keep dozens of human testers occupied for days or weeks if conducted
|
|
manually.
|
|
|
|
However, there are times when the automated tests do not cover a particular
|
|
scenario and manual testing is desired. It turns out that it is simple to
|
|
adapt a test to stop and wait after the Ceph installation phase, and the
|
|
engineer can then ssh into the running cluster.
|
|
|
|
This common use case is currently provided for by the following command::
|
|
|
|
ceph-workbench ceph-qa-suite --simultaneous-jobs 9 --verbose
|
|
--teuthology-git-url http://github.com/dachary/teuthology
|
|
--teuthology-branch openstack --ceph-qa-suite-git-url
|
|
http://github.com/dachary/ceph-qa-suite --suite-branch wip-ceph-disk
|
|
--ceph-git-url http://github.com/ceph/ceph --ceph jewel --suite
|
|
ceph-disk --filter ubuntu_14
|
|
|
|
This builds packages from the Ceph git repository and branch specified in
|
|
the ``--ceph-git-url`` and ``--ceph`` options, respectively, provisions VMs
|
|
in OpenStack, installs the packages, and deploys a Ceph cluster on them.
|
|
Then, instead of running automated tests, it stops and enters a wait loop.
|
|
|
|
The VMs (or "instances" in OpenStack terminology) created by
|
|
`ceph-workbench ceph-qa-suite`_ are named as follows:
|
|
|
|
``teuthology`` - the teuthology machine
|
|
|
|
``packages-repository`` - VM where packages are stored
|
|
|
|
``ceph-*`` - VM where packages are built
|
|
|
|
``target*`` - machines where tests are run
|
|
|
|
The VMs named ``target*`` are used by tests. If you are monitoring the
|
|
teuthology log for a given test, the hostnames of these target machines can
|
|
be found out by searching for the string ``Locked targets``::
|
|
|
|
2016-03-20T11:39:06.166 INFO:teuthology.task.internal:Locked targets:
|
|
target149202171058.teuthology: null
|
|
target149202171059.teuthology: null
|
|
|
|
The IP addresses of the target machines can be found by running
|
|
``openstack server list`` on the teuthology machine.
|
|
|
|
The whole process, which takes some time to complete, can be monitored as
|
|
described in `Run the dummy suite`_. Be patient.
|
|
|
|
Once the target machines are up and running and the test enters its wait
|
|
loop, the engineer can ssh into the target machines and do whatever manual
|
|
testing is required. Use the teuthology machine as jump host.
|
|
|
|
|
|
.. WIP
|
|
.. ===
|
|
..
|
|
.. Building RPM packages
|
|
.. ---------------------
|
|
..
|
|
.. Ceph is regularly built and packaged for a number of major Linux
|
|
.. distributions. At the time of this writing, these included CentOS, Debian,
|
|
.. Fedora, openSUSE, and Ubuntu.
|
|
..
|
|
.. Architecture
|
|
.. ============
|
|
..
|
|
.. Ceph is a collection of components built on top of RADOS and provide
|
|
.. services (RBD, RGW, CephFS) and APIs (S3, Swift, POSIX) for the user to
|
|
.. store and retrieve data.
|
|
..
|
|
.. See :doc:`/architecture` for an overview of Ceph architecture. The
|
|
.. following sections treat each of the major architectural components
|
|
.. in more detail, with links to code and tests.
|
|
..
|
|
.. FIXME The following are just stubs. These need to be developed into
|
|
.. detailed descriptions of the various high-level components (RADOS, RGW,
|
|
.. etc.) with breakdowns of their respective subcomponents.
|
|
..
|
|
.. FIXME Later, in the Testing chapter I would like to take another look
|
|
.. at these components/subcomponents with a focus on how they are tested.
|
|
..
|
|
.. RADOS
|
|
.. -----
|
|
..
|
|
.. RADOS stands for "Reliable, Autonomic Distributed Object Store". In a Ceph
|
|
.. cluster, all data are stored in objects, and RADOS is the component responsible
|
|
.. for that.
|
|
..
|
|
.. RADOS itself can be further broken down into Monitors, Object Storage Daemons
|
|
.. (OSDs), and client APIs (librados). Monitors and OSDs are introduced at
|
|
.. :doc:`/start/intro`. The client library is explained at
|
|
.. :doc:`/rados/api/index`.
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..
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.. RGW
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.. ---
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..
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.. RGW stands for RADOS Gateway. Using the embedded HTTP server civetweb_ or
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.. Apache FastCGI, RGW provides a REST interface to RADOS objects.
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..
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.. .. _civetweb: https://github.com/civetweb/civetweb
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..
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.. A more thorough introduction to RGW can be found at :doc:`/radosgw/index`.
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..
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.. RBD
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.. ---
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..
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.. RBD stands for RADOS Block Device. It enables a Ceph cluster to store disk
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.. images, and includes in-kernel code enabling RBD images to be mounted.
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..
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.. To delve further into RBD, see :doc:`/rbd/rbd`.
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..
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.. CephFS
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.. ------
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..
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.. CephFS is a distributed file system that enables a Ceph cluster to be used as a NAS.
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..
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.. File system metadata is managed by Meta Data Server (MDS) daemons. The Ceph
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.. file system is explained in more detail at :doc:`/cephfs/index`.
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..
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