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diff --git a/poky/documentation/test-manual/test-manual-understand-autobuilder.xml b/poky/documentation/test-manual/test-manual-understand-autobuilder.xml new file mode 100644 index 000000000..a04006605 --- /dev/null +++ b/poky/documentation/test-manual/test-manual-understand-autobuilder.xml @@ -0,0 +1,314 @@ +<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" +"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd" +[<!ENTITY % poky SYSTEM "../poky.ent"> %poky; ] > +<!--SPDX-License-Identifier: CC-BY-2.0-UK--> + +<chapter id='test-manual-understand-autobuilder'> + +<title>Understanding the Yocto Project Autobuilder</title> + <section> + <title>Execution Flow within the Autobuilder</title> + <para>The “a-full” and “a-quick” targets are the usual entry points into the Autobuilder and + it makes sense to follow the process through the system starting there. This is best + visualised from the Autobuilder Console view (<link linkend="" + >https://autobuilder.yoctoproject.org/typhoon/#/console</link>). </para> + <para>Each item along the top of that view represents some “target build” and these targets + are all run in parallel. The ‘full’ build will trigger the majority of them, the “quick” + build will trigger some subset of them. The Autobuilder effectively runs whichever + configuration is defined for each of those targets on a seperate buildbot worker. To + understand the configuration, you need to look at the entry on + <filename>config.json</filename> file within the + <filename>yocto-autobuilder-helper</filename> repository. The targets are defined in + the ‘overrides’ section, a quick example could be qemux86-64 which looks + like:<literallayout class="monospaced"> + "qemux86-64" : { + "MACHINE" : "qemux86-64", + "TEMPLATE" : "arch-qemu", + "step1" : { + "extravars" : [ + "IMAGE_FSTYPES_append = ' wic wic.bmap'" + ] + } + }, + </literallayout>And + to expand that, you need the “arch-qemu” entry from the “templates” section, which looks + like:<literallayout class="monospaced"> + "arch-qemu" : { + "BUILDINFO" : true, + "BUILDHISTORY" : true, + "step1" : { + "BBTARGETS" : "core-image-sato core-image-sato-dev core-image-sato-sdk core-image-minimal core-image-minimal-dev core-image-sato:do_populate_sdk", + "SANITYTARGETS" : "core-image-minimal:do_testimage core-image-sato:do_testimage core-image-sato-sdk:do_testimage core-image-sato:do_testsdk" + }, + "step2" : { + "SDKMACHINE" : "x86_64", + "BBTARGETS" : "core-image-sato:do_populate_sdk core-image-minimal:do_populate_sdk_ext core-image-sato:do_populate_sdk_ext", + "SANITYTARGETS" : "core-image-sato:do_testsdk core-image-minimal:do_testsdkext core-image-sato:do_testsdkext" + }, + "step3" : { + "BUILDHISTORY" : false, + "EXTRACMDS" : ["${SCRIPTSDIR}/checkvnc; DISPLAY=:1 oe-selftest ${HELPERSTMACHTARGS} -j 15"], + "ADDLAYER" : ["${BUILDDIR}/../meta-selftest"] + } + }, + </literallayout>Combining + these two entries you can see that “qemux86-64” is a three step build where the + <filename>bitbake BBTARGETS</filename> would be run, then <filename>bitbake + SANITYTARGETS</filename> for each step; all for + <filename>MACHINE=”qemx86-64”</filename> but with differing SDKMACHINE settings. In + step 1 an extra variable is added to the <filename>auto.conf</filename> file to enable + wic image generation.</para> + <para>While not every detail of this is covered here, you can see how the templating + mechanism allows quite complex configurations to be built up yet allows duplication and + repetition to be kept to a minimum.</para> + <para>The different build targets are designed to allow for parallelisation, so different + machines are usually built in parallel, operations using the same machine and metadata + are built sequentially, with the aim of trying to optimise build efficiency as much as + possible.</para> + <para>The <filename>config.json</filename> file is processed by the scripts in the Helper + repository in the <filename>scripts</filename> directory. The following section details + how this works.</para> + </section> + + <section id='test-autobuilder-target-exec-overview'> + <title>Autobuilder Target Execution Overview</title> + + <para>For each given target in a build, the Autobuilder executes several steps. These are + configured in <filename>yocto-autobuilder2/builders.py</filename> and roughly consist + of: <orderedlist> + <listitem id='test-list-tgt-exec-clobberdir'> + <para><emphasis>Run <filename>clobberdir</filename></emphasis></para> + <para>This cleans out any previous build. Old builds are left around to allow + easier debugging of failed builds. For additional information, see <link + linkend="test-clobberdir"><filename>clobberdir</filename></link>.</para> + </listitem> + <listitem> + <para><emphasis>Obtain yocto-autobuilder-helper</emphasis></para> + <para>This step clones the <filename>yocto-autobuilder-helper</filename> git + repository. This is necessary to prevent the requirement to maintain all the + release or project-specific code within Buildbot. The branch chosen matches + the release being built so we can support older releases and still make + changes in newer ones.</para> + </listitem> + <listitem> + <para><emphasis>Write layerinfo.json</emphasis></para> + <para>This transfers data in the Buildbot UI when the build was configured to + the Helper.</para> + </listitem> + <listitem> + <para><emphasis>Call scripts/shared-repo-unpack</emphasis></para> + <para>This is a call into the Helper scripts to set up a checkout of all the + pieces this build might need. It might clone the BitBake repository and the + OpenEmbedded-Core repository. It may clone the Poky repository, as well as + additional layers. It will use the data from the + <filename>layerinfo.json</filename> file to help understand the + configuration. It will also use a local cache of repositories to speed up + the clone checkouts. For additional information, see <link + linkend="test-autobuilder-clone-cache">Autobuilder Clone + Cache</link>.</para> + <para>This step has two possible modes of operation. If the build is part of a + parent build, its possible that all the repositories needed may already be + available, ready in a pre-prepared directory. An "a-quick" or "a-full" build + would prepare this before starting the other sub-target builds. This is done + for two reasons:<itemizedlist> + <listitem> + <para>the upstream may change during a build, for example, from a + forced push and this ensures we have matching content for the + whole build</para> + </listitem> + <listitem> + <para>if 15 Workers all tried to pull the same data from the same + repos, we can hit resource limits on upstream servers as they + can think they are under some kind of network attack</para> + </listitem> + </itemizedlist>This pre-prepared directory is shared among the Workers over + NFS. If the build is an individual build and there is no "shared" directory + available, it would clone from the cache and the upstreams as necessary. + This is considered the fallback mode.</para> + </listitem> + <listitem> + <para><emphasis>Call scripts/run-config</emphasis></para> + <para>This is another call into the Helper scripts where its expected that the + main functionality of this target will be executed.</para> + </listitem> + </orderedlist></para> + </section> + <section id='test-autobuilder-tech'> + <title>Autobuilder Technology</title> + <para>The Autobuilder has Yocto Project-specific functionality to allow builds to operate + with increased efficiency and speed.</para> + <section id='test-clobberdir'> + <title>clobberdir</title> + <para>When deleting files, the Autobuilder uses <filename>clobberdir</filename>, which + is a special script that moves files to a special location, rather than deleting + them. Files in this location are deleted by an <filename>rm</filename> command, + which is run under <filename>ionice -c 3</filename>. For example, the deletion only + happens when there is idle IO capacity on the Worker. The Autobuilder Worker Janitor + runs this deletion. See <link linkend="test-autobuilder-worker-janitor">Autobuilder + Worker Janitor</link>.</para> + </section> + <section id='test-autobuilder-clone-cache'> + <title>Autobuilder Clone Cache</title> + <para>Cloning repositories from scratch each time they are required was slow on the + Autobuilder. We therefore have a stash of commonly used repositories pre-cloned on + the Workers. Data is fetched from these during clones first, then "topped up" with + later revisions from any upstream when necesary. The cache is maintained by the + Autobuilder Worker Janitor. See <link linkend="test-autobuilder-worker-janitor" + >Autobuilder Worker Janitor</link>.</para> + </section> + <section id='test-autobuilder-worker-janitor'> + <title>Autobuilder Worker Janitor</title> + <para>This is a process running on each Worker that performs two basic operations, + including background file deletion at IO idle (see <link + linkend="test-list-tgt-exec-clobberdir">Target Execution: clobberdir</link>) and + maintainenance of a cache of cloned repositories to improve the speed the system can + checkout repositories.</para> + </section> + <section id='test-shared-dl-dir'> + <title>Shared DL_DIR</title> + <para>The Workers are all connected over NFS which allows DL_DIR to be shared between + them. This reduces network accesses from the system and allows the build to be sped + up. Usage of the directory within the build system is designed to be able to be + shared over NFS.</para> + </section> + <section id='test-shared-sstate-cache'> + <title>Shared SSTATE_DIR</title> + <para>The Workers are all connected over NFS which allows the + <filename>sstate</filename> directory to be shared between them. This means once + a Worker has built an artefact, all the others can benefit from it. Usage of the + directory within the directory is designed for sharing over NFS.</para> + </section> + <section id='test-resulttool'> + <title>Resulttool</title> + <para>All of the different tests run as part of the build generate output into + <filename>testresults.json</filename> files. This allows us to determine which + tests ran in a given build and their status. Additional information, such as failure + logs or the time taken to run the tests, may also be included.</para> + <para>Resulttool is part of OpenEmbedded-Core and is used to manipulate these json + results files. It has the ability to merge files together, display reports of the + test results and compare different result files.</para> + <para>For details, see <link linkend="" + >https://wiki.yoctoproject.org/wiki/Resulttool</link>.</para> + </section> + </section> + <section id='test-run-config-tgt-execution'> + <title>run-config Target Execution</title> + <para>The <filename>scripts/run-config</filename> execution is where most of the work within + the Autobuilder happens. It runs through a number of steps; the first are general setup + steps that are run once and include:<orderedlist> + <listitem> + <para>Set up any <filename>buildtools-tarball</filename> if configured.</para> + </listitem> + <listitem> + <para>Call "buildhistory-init" if buildhistory is configured.</para> + </listitem> + </orderedlist></para> + <para>For each step that is configured in <filename>config.json</filename>, it will perform + the following:</para> + <para> + <remark>## WRITER's question: What does "logging in as stepXa" and others refer to + below? ##</remark> + <orderedlist> + <listitem id="test-run-config-add-layers-step"> + <para dir="ltr">Add any layers that are specified using the + <filename>bitbake-layers add-layer</filename> command (logging as + stepXa)</para> + </listitem> + <listitem> + <para dir="ltr">Call the <filename>scripts/setup-config</filename> script to + generate the necessary <filename>auto.conf</filename> configuration file for + the build</para> + </listitem> + <listitem> + <para dir="ltr">Run the <filename>bitbake BBTARGETS</filename> command (logging + as stepXb)</para> + </listitem> + <listitem> + <para dir="ltr">Run the <filename>bitbake SANITYTARGETS</filename> command + (logging as stepXc)</para> + </listitem> + <listitem> + <para dir="ltr">Run the <filename>EXTRACMDS</filename> command, which are run + within the BitBake build environment (logging as stepXd)</para> + </listitem> + <listitem> + <para dir="ltr">Run the <filename>EXTRAPLAINCMDS</filename> command(s), which + are run outside the BitBake build environment (logging as stepXd)</para> + </listitem> + <listitem> + <para dir="ltr">Remove any layers added in <link + linkend="test-run-config-add-layers-step">step 1</link> using the + <filename>bitbake-layers remove-layer</filename> command (logging as + stepXa)</para> + </listitem> + </orderedlist> + </para> + <para>Once the execution steps above complete, <filename>run-config</filename> executes a + set of post-build steps, including:<orderedlist> + <listitem> + <para dir="ltr">Call <filename>scripts/publish-artifacts</filename> to collect + any output which is to be saved from the build.</para> + </listitem> + <listitem> + <para dir="ltr">Call <filename>scripts/collect-results</filename> to collect any + test results to be saved from the build.</para> + </listitem> + <listitem> + <para dir="ltr">Call <filename>scripts/upload-error-reports</filename> to send + any error reports generated to the remote server.</para> + </listitem> + <listitem> + <para dir="ltr">Cleanup the build directory using <link + linkend="test-clobberdir"><filename>clobberdir</filename></link> if the + build was successful, else rename it to “build-renamed” for potential future + debugging.</para> + </listitem> + </orderedlist></para> + </section> + <section id='test-deploying-yp-autobuilder'> + <title>Deploying Yocto Autobuilder</title> + <para>The most up to date information about how to setup and deploy your own Autbuilder can + be found in README.md in the <filename>yocto-autobuilder2</filename> repository.</para> + <para>We hope that people can use the <filename>yocto-autobuilder2</filename> code directly + but it is inevitable that users will end up needing to heavily customise the + <filename>yocto-autobuilder-helper</filename> repository, particularly the + <filename>config.json</filename> file as they will want to define their own test + matrix.</para> + <para>The Autobuilder supports wo customization options: <itemizedlist> + <listitem> + <para>variable substitution</para> + </listitem> + <listitem> + <para>overlaying configuration files</para> + </listitem> + </itemizedlist>The standard <filename>config.json</filename> minimally attempts to allow + substitution of the paths. The Helper script repository includes a + <filename>local-example.json</filename> file to show how you could override these + from a separate configuration file. Pass the following into the environment of the + Autobuilder:<literallayout class="monospaced"> + $ ABHELPER_JSON="config.json local-example.json" + </literallayout>As + another example, you could also pass the following into the + environment:<literallayout class="monospaced"> + $ ABHELPER_JSON="config.json <replaceable>/some/location/</replaceable>local.json" + </literallayout>One + issue users often run into is validation of the <filename>config.json</filename> files. + A tip for minimizing issues from invalid json files is to use a Git + <filename>pre-commit-hook.sh</filename> script to verify the JSON file before + committing it. Create a symbolic link as + follows:<literallayout class="monospaced"> + $ ln -s ../../scripts/pre-commit-hook.sh .git/hooks/pre-commit + </literallayout></para> + </section> + + + + + + + + +</chapter> +<!-- +vim: expandtab tw=80 ts=4 +--> |