summaryrefslogtreecommitdiffstats
path: root/documentation/test-manual/test-manual-understand-autobuilder.xml
diff options
context:
space:
mode:
Diffstat (limited to 'documentation/test-manual/test-manual-understand-autobuilder.xml')
-rw-r--r--documentation/test-manual/test-manual-understand-autobuilder.xml312
1 files changed, 312 insertions, 0 deletions
diff --git a/documentation/test-manual/test-manual-understand-autobuilder.xml b/documentation/test-manual/test-manual-understand-autobuilder.xml
new file mode 100644
index 0000000000..7541305350
--- /dev/null
+++ b/documentation/test-manual/test-manual-understand-autobuilder.xml
@@ -0,0 +1,312 @@
1<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
2"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
3[<!ENTITY % poky SYSTEM "../poky.ent"> %poky; ] >
4
5<chapter id='test-manual-understand-autobuilder'>
6
7<title>Understanding the Yocto Project Autobuilder</title>
8 <section>
9 <title>Execution Flow within the Autobuilder</title>
10 <para>The “a-full” and “a-quick” targets are the usual entry points into the Autobuilder and
11 it makes sense to follow the process through the system starting there. This is best
12 visualised from the Autobuilder Console view (<link linkend=""
13 >https://autobuilder.yoctoproject.org/typhoon/#/console</link>). </para>
14 <para>Each item along the top of that view represents some “target build” and these targets
15 are all run in parallel. The ‘full’ build will trigger the majority of them, the “quick”
16 build will trigger some subset of them. The Autobuilder effectively runs whichever
17 configuration is defined for each of those targets on a seperate buildbot worker. To
18 understand the configuration, you need to look at the entry on
19 <filename>config.json</filename> file within the
20 <filename>yocto-autobuilder-helper</filename> repository. The targets are defined in
21 the ‘overrides’ section, a quick example could be qemux86-64 which looks
22 like:<literallayout>
23 "qemux86-64" : {
24 "MACHINE" : "qemux86-64",
25 "TEMPLATE" : "arch-qemu",
26 "step1" : {
27 "extravars" : [
28 "IMAGE_FSTYPES_append = ' wic wic.bmap'"
29 ]
30 }
31 },
32 </literallayout>And
33 to expand that, you need the “arch-qemu” entry from the “templates” section, which looks
34 like:<literallayout>
35 "arch-qemu" : {
36 "BUILDINFO" : true,
37 "BUILDHISTORY" : true,
38 "step1" : {
39 "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",
40 "SANITYTARGETS" : "core-image-minimal:do_testimage core-image-sato:do_testimage core-image-sato-sdk:do_testimage core-image-sato:do_testsdk"
41 },
42 "step2" : {
43 "SDKMACHINE" : "x86_64",
44 "BBTARGETS" : "core-image-sato:do_populate_sdk core-image-minimal:do_populate_sdk_ext core-image-sato:do_populate_sdk_ext",
45 "SANITYTARGETS" : "core-image-sato:do_testsdk core-image-minimal:do_testsdkext core-image-sato:do_testsdkext"
46 },
47 "step3" : {
48 "BUILDHISTORY" : false,
49 "EXTRACMDS" : ["${SCRIPTSDIR}/checkvnc; DISPLAY=:1 oe-selftest ${HELPERSTMACHTARGS} -j 15"],
50 "ADDLAYER" : ["${BUILDDIR}/../meta-selftest"]
51 }
52 },
53 </literallayout>Combining
54 these two entries you can see that “qemux86-64” is a three step build where the “bitbake
55 BBTARGETS” would be run, then “bitbake SANITYTARGETS” for each step; all for
56 MACHINE=”qemx86-64” but with differing SDKMACHINE settings. In step 1 an extra variable
57 is added to the <filename>auto.conf</filename> file to enable wic image
58 generation.</para>
59 <para>While not every detail of this is covered here, you can see how the templating
60 mechanism allows quite complex configurations to be built up yet allows duplication and
61 repetition to be kept to a minimum.</para>
62 <para>The different build targets are designed to allow for parallelisation, so different
63 machines are usually built in parallel, operations using the same machine and metadata
64 are built sequentially, with the aim of trying to optimise build efficiency as much as
65 possible.</para>
66 <para>The <filename>config.json</filename> file is processed by the scripts in the Helper
67 repository in the <filename>scripts</filename> directory. The following section details
68 how this works.</para>
69 </section>
70
71 <section id='test-autobuilder-target-exec-overview'>
72 <title>Autobuilder Target Execution Overview</title>
73
74 <para>For each given target in a build, the Autobuilder executes several steps. These are
75 configured in <filename>yocto-autobuilder2/builders.py</filename> and roughly consist
76 of: <orderedlist>
77 <listitem id='test-list-tgt-exec-clobberdir'>
78 <para><emphasis>Run <filename>clobberdir</filename></emphasis></para>
79 <para>This cleans out any previous build. Old builds are left around to allow
80 easier debugging of failed builds. For additional information, see <link
81 linkend="test-clobberdir"><filename>clobberdir</filename></link>.</para>
82 </listitem>
83 <listitem>
84 <para><emphasis>Obtain yocto-autobuilder-helper</emphasis></para>
85 <para>This step clones the <filename>yocto-autobuilder-helper</filename> git
86 repository. This is necessary to prevent the requirement to maintain all the
87 release or project-specific code within Buildbot. The branch chosen matches
88 the release being built so we can support older releases and still make
89 changes in newer ones.</para>
90 </listitem>
91 <listitem>
92 <para><emphasis>Write layerinfo.json</emphasis></para>
93 <para>This transfers data in the Buildbot UI when the build was configured to
94 the Helper.</para>
95 </listitem>
96 <listitem>
97 <para><emphasis>Call scripts/shared-repo-unpack</emphasis></para>
98 <para>This is a call into the Helper scripts to set up a checkout of all the
99 pieces this build might need. It might clone the BitBake repository and the
100 OpenEmbedded-Core repository. It may clone the Poky repository, as well as
101 additional layers. It will use the data from the
102 <filename>layerinfo.json</filename> file to help understand the
103 configuration. It will also use a local cache of repositories to speed up
104 the clone checkouts. For additional information, see <link
105 linkend="test-autobuilder-clone-cache">Autobuilder Clone
106 Cache</link>.</para>
107 <para>This step has two possible modes of operation. If the build is part of a
108 parent build, its possible that all the repositories needed may already be
109 available, ready in a pre-prepared directory. An "a-quick" or "a-full" build
110 would prepare this before starting the other sub-target builds. This is done
111 for two reasons:<itemizedlist>
112 <listitem>
113 <para>the upstream may change during a build, for example, from a
114 forced push and this ensures we have matching content for the
115 whole build</para>
116 </listitem>
117 <listitem>
118 <para>if 15 Workers all tried to pull the same data from the same
119 repos, we can hit resource limits on upstream servers as they
120 can think they are under some kind of network attack</para>
121 </listitem>
122 </itemizedlist>This pre-prepared directory is shared among the Workers over
123 NFS. If the build is an individual build and there is no "shared" directory
124 available, it would clone from the cache and the upstreams as necessary.
125 This is considered the fallback mode.</para>
126 </listitem>
127 <listitem>
128 <para><emphasis>Call scripts/run-config</emphasis></para>
129 <para>This is another call into the Helper scripts where its expected that the
130 main functionality of this target will be executed.</para>
131 </listitem>
132 </orderedlist></para>
133 </section>
134 <section id='test-autobuilder-tech'>
135 <title>Autobuilder Technology</title>
136 <para>The Autobuilder has Yocto Project-specific functionality to allow builds to operate
137 with increased efficiency and speed.</para>
138 <section id='test-clobberdir'>
139 <title>clobberdir</title>
140 <para>When deleting files, the Autobuilder uses <filename>clobberdir</filename>, which
141 is a special script that moves files to a special location, rather than deleting
142 them. Files in this location are deleted by an <filename>rm</filename> command,
143 which is run under <filename>ionice -c 3</filename>. For example, the deletion only
144 happens when there is idle IO capacity on the Worker. The Autobuilder Worker Janitor
145 runs this deletion. See <link linkend="test-autobuilder-worker-janitor">Autobuilder
146 Worker Janitor</link>.</para>
147 </section>
148 <section id='test-autobuilder-clone-cache'>
149 <title>Autobuilder Clone Cache</title>
150 <para>Cloning repositories from scratch each time they are required was slow on the
151 Autobuilder. We therefore have a stash of commonly used repositories pre-cloned on
152 the Workers. Data is fetched from these during clones first, then "topped up" with
153 later revisions from any upstream when necesary. The cache is maintained by the
154 Autobuilder Worker Janitor. See <link linkend="test-autobuilder-worker-janitor"
155 >Autobuilder Worker Janitor</link>.</para>
156 </section>
157 <section id='test-autobuilder-worker-janitor'>
158 <title>Autobuilder Worker Janitor</title>
159 <para>This is a process running on each Worker that performs two basic operations,
160 including background file deletion at IO idle (see <link
161 linkend="test-list-tgt-exec-clobberdir">Target Execution: clobberdir</link>) and
162 maintainenance of a cache of cloned repositories to improve the speed the system can
163 checkout repositories.</para>
164 </section>
165 <section id='test-shared-dl-dir'>
166 <title>Shared DL_DIR</title>
167 <para>The Workers are all connected over NFS which allows DL_DIR to be shared between
168 them. This reduces network accesses from the system and allows the build to be sped
169 up. Usage of the directory within the build system is designed to be able to be
170 shared over NFS.</para>
171 </section>
172 <section id='test-shared-sstate-cache'>
173 <title>Shared SSTATE_DIR</title>
174 <para>The Workers are all connected over NFS which allows the
175 <filename>sstate</filename> directory to be shared between them. This means once
176 a Worker has built an artefact, all the others can benefit from it. Usage of the
177 directory within the directory is designed for sharing over NFS.</para>
178 </section>
179 <section id='test-resulttool'>
180 <title>Resulttool</title>
181 <para>All of the different tests run as part of the build generate output into
182 <filename>testresults.json</filename> files. This allows us to determine which
183 tests ran in a given build and their status. Additional information, such as failure
184 logs or the time taken to run the tests, may also be included.</para>
185 <para>Resulttool is part of OpenEmbedded-Core and is used to manipulate these json
186 results files. It has the ability to merge files together, display reports of the
187 test results and compare different result files.</para>
188 <para>For details, see <link linkend=""
189 >https://wiki.yoctoproject.org/wiki/Resulttool</link>.</para>
190 </section>
191 </section>
192 <section id='test-run-config-tgt-execution'>
193 <title>run-config Target Execution</title>
194 <para>The <filename>scripts/run-config</filename> execution is where most of the work within
195 the Autobuilder happens. It runs through a number of steps; the first are general setup
196 steps that are run once and include:<orderedlist>
197 <listitem>
198 <para>Set up any <filename>buildtools-tarball</filename> if configured.</para>
199 </listitem>
200 <listitem>
201 <para>Call "buildhistory-init" if buildhistory is configured.</para>
202 </listitem>
203 </orderedlist></para>
204 <para>For each step that is configured in <filename>config.json</filename>, it will perform
205 the following:</para>
206 <para>
207 <remark>## WRITER's question: What does "logging in as stepXa" and others refer to
208 below? ##</remark>
209 <orderedlist>
210 <listitem id="test-run-config-add-layers-step">
211 <para dir="ltr">Add any layers that are specified using the
212 <filename>bitbake-layers add-layer</filename> command (logging as
213 stepXa)</para>
214 </listitem>
215 <listitem>
216 <para dir="ltr">Call the <filename>scripts/setup-config</filename> script to
217 generate the necessary <filename>auto.conf</filename> configuration file for
218 the build</para>
219 </listitem>
220 <listitem>
221 <para dir="ltr">Run the <filename>bitbake BBTARGETS</filename> command (logging
222 as stepXb)</para>
223 </listitem>
224 <listitem>
225 <para dir="ltr">Run the <filename>bitbake SANITYTARGETS</filename> command
226 (logging as stepXc)</para>
227 </listitem>
228 <listitem>
229 <para dir="ltr">Run the <filename>EXTRACMDS</filename> command, which are run
230 within the BitBake build environment (logging as stepXd)</para>
231 </listitem>
232 <listitem>
233 <para dir="ltr">Run the <filename>EXTRAPLAINCMDS</filename> command(s), which
234 are run outside the BitBake build environment (logging as stepXd)</para>
235 </listitem>
236 <listitem>
237 <para dir="ltr">Remove any layers added in <link
238 linkend="test-run-config-add-layers-step">step 1</link> using the
239 <filename>bitbake-layers remove-layer</filename> command (logging as
240 stepXa)</para>
241 </listitem>
242 </orderedlist>
243 </para>
244 <para>Once the execution steps above complete, <filename>run-config</filename> executes a
245 set of post-build steps, including:<orderedlist>
246 <listitem>
247 <para dir="ltr">Call <filename>scripts/publish-artifacts</filename> to collect
248 any output which is to be saved from the build.</para>
249 </listitem>
250 <listitem>
251 <para dir="ltr">Call <filename>scripts/collect-results</filename> to collect any
252 test results to be saved from the build.</para>
253 </listitem>
254 <listitem>
255 <para dir="ltr">Call <filename>scripts/upload-error-reports</filename> to send
256 any error reports generated to the remote server.</para>
257 </listitem>
258 <listitem>
259 <para dir="ltr">Cleanup the build directory using <link
260 linkend="test-clobberdir"><filename>clobberdir</filename></link> if the
261 build was successful, else rename it to “build-renamed” for potential future
262 debugging.</para>
263 </listitem>
264 </orderedlist></para>
265 </section>
266 <section id='test-deploying-yp-autobuilder'>
267 <title>Deploying Yocto Autobuilder</title>
268 <para>The most up to date information about how to setup and deploy your own Autbuilder can
269 be found in README.md in the <filename>yocto-autobuilder2</filename> repository.</para>
270 <para>We hope that people can use the <filename>yocto-autobuilder2</filename> code directly
271 but it is inevitable that users will end up needing to heavily customise the
272 <filename>yocto-autobuilder-helper</filename> repository, particularly the
273 <filename>config.json</filename> file as they will want to define their own test
274 matrix.</para>
275 <para>The Autobuilder supports wo customization options: <itemizedlist>
276 <listitem>
277 <para>variable substitution</para>
278 </listitem>
279 <listitem>
280 <para>overlaying configuration files</para>
281 </listitem>
282 </itemizedlist>The standard <filename>config.json</filename> minimally attempts to allow
283 substitution of the paths. The Helper script repository includes a
284 <filename>local-example.json</filename> file to show how you could override these
285 from a separate configuration file. Pass the following into the environment of the
286 Autobuilder:<literallayout>
287 $ ABHELPER_JSON="config.json local-example.json"
288 </literallayout>As
289 another example, you could also pass the following into the
290 environment:<literallayout>
291 $ ABHELPER_JSON="config.json <replaceable>/some/location/</replaceable>local.json"
292 </literallayout>One
293 issue users often run into is validation of the <filename>config.json</filename> files.
294 A tip for minimizing issues from invalid json files is to use a Git
295 <filename>pre-commit-hook.sh</filename> script to verify the JSON file before
296 committing it. Create a symbolic link as
297 follows:<literallayout>
298 $ ln -s ../../scripts/pre-commit-hook.sh .git/hooks/pre-commit
299 </literallayout></para>
300 </section>
301
302
303
304
305
306
307
308
309</chapter>
310<!--
311vim: expandtab tw=80 ts=4
312-->
generated by cgit v1.2.3-54-g00ecf (git 2.39.0) at 2024-05-26 02:25:18 +0000