Deadlock in Rendering stage #2926
Description
Describe the bug
When running Dokka on machines with less than two CPU cores, certain projects end up causing a deadlock during the rendering stage.
Expected behaviour
Dokka should continue building documentation without any issue, and not cause a deadlock.
To Reproduce
It seems to occur specifically in our firebase-common artifact over at firebase-android-sdk when building our docs.
If you clone our repo in a VM or Docker container that is limited to two CPU cores- and run ./gradlew :firebase-common:kotlindoc, it will freeze during the rendering stage.
Dokka configuration
I've uploaded it as a gist since it's a bit lengthy.
Installation
- Operating system: Linux
- Build tool: Gradle v7.6.0
- Dokka version: 1.8.10-dev-203
Additional context
After getting copies of Github's runner images, and simulating the environment in a docker image- I've managed to reproduce the issue. This occurs when the CPUs are limited to 2 cores; as is the case with standard github runner machines. It seems to be a deadlock. Logging into the deadlocked container, I've managed to get stack traces.
Relevant Running Processes:
root 205 199 1 20:12 pts/1 00:00:13 /opt/hostedtoolcache/Java_Zulu_jdk/11.0.18-10/x64/bin/java -Xmx64m -Xms64m -Dorg.gradle.appname=gradlew -classpath /usr/local/google/home/daymxn/Documents/repos/firebase-android-sdk/gradle/wrapper/gradle-wrapper.jar org.gradle.wrapper.GradleWrapperMain --no-daem
on :firebase-common:kotlindoc
root 241 205 25 20:13 ? 00:05:42 /opt/hostedtoolcache/Java_Zulu_jdk/11.0.18-10/x64/bin/java -XX:MaxPermSize=8g --add-opens=java.base/java.util=ALL-UNNAMED --add-opens=java.base/java.lang=ALL-UNNAMED --add-opens=java.base/java.lang.invoke=ALL-UNNAMED --add-opens=java.prefs/java.util.prefs=ALL-UN
NAMED --add-opens=java.base/java.nio.charset=ALL-UNNAMED --add-opens=java.base/java.net=ALL-UNNAMED --add-opens=java.base/java.util.concurrent.atomic=ALL-UNNAMED -Xms2g -Xmx8g -Dfile.encoding=UTF-8 -Duser.country -Duser.language=en -Duser.variant -cp /root/.gradle/wrapper/dists/gradle-7.6-all/9f832ih6bniajn45pbmq
hk2cw/gradle-7.6/lib/gradle-launcher-7.6.jar org.gradle.launcher.daemon.bootstrap.GradleDaemon 7.6
root 343 241 3 20:14 ? 00:00:39 /opt/hostedtoolcache/Java_Zulu_jdk/11.0.18-10/x64/bin/java -cp /root/.gradle/caches/modules-2/files-2.1/org.jetbrains.kotlin/kotlin-compiler-embeddable/1.7.10/909803167c98606fcf22b4c848647c68e351d48d/kotlin-compiler-embeddable-1.7.10.jar:/root/.gradle/caches/mod
ules-2/files-2.1/org.jetbrains.kotlin/kotlin-reflect/1.7.10/165e600dfea6185cf5efa700756294cc4904dbeb/kotlin-reflect-1.7.10.jar:/root/.gradle/caches/modules-2/files-2.1/org.jetbrains.kotlin/kotlin-stdlib/1.7.10/d2abf9e77736acc4450dc4a3f707fa2c10f5099d/kotlin-stdlib-1.7.10.jar:/root/.gradle/caches/modules-2/files-2
.1/org.jetbrains.kotlin/kotlin-script-runtime/1.7.10/c99c87a6988d8fd8d5142e9ed5c9f34a7cf561ee/kotlin-script-runtime-1.7.10.jar:/root/.gradle/caches/modules-2/files-2.1/org.jetbrains.kotlin/kotlin-daemon-embeddable/1.7.10/3a9f7aef7080d3ae63126cbba4f827ed664f32fa/kotlin-daemon-embeddable-1.7.10.jar:/root/.gradle/ca
ches/modules-2/files-2.1/org.jetbrains.intellij.deps/trove4j/1.0.20200330/3afb14d5f9ceb459d724e907a21145e8ff394f02/trove4j-1.0.20200330.jar:/root/.gradle/caches/modules-2/files-2.1/net.java.dev.jna/jna/5.6.0/330f2244e9030119ab3030fc3fededc86713d9cc/jna-5.6.0.jar:/root/.gradle/caches/modules-2/files-2.1/org.jetbra
ins.kotlin/kotlin-stdlib-common/1.7.10/bac80c520d0a9e3f3673bc2658c6ed02ef45a76a/kotlin-stdlib-common-1.7.10.jar:/root/.gradle/caches/modules-2/files-2.1/org.jetbrains/annotations/13.0/919f0dfe192fb4e063e7dacadee7f8bb9a2672a9/annotations-13.0.jar -Djava.awt.headless=true -D$java.rmi.server.hostname=127.0.0.1 -Xmx8
g -Dkotlin.environment.keepalive -ea org.jetbrains.kotlin.daemon.KotlinCompileDaemon --daemon-runFilesPath /root/.local/share/kotlin/daemon --daemon-autoshutdownIdleSeconds=7200 --daemon-compilerClasspath /root/.gradle/caches/modules-2/files-2.1/org.jetbrains.kotlin/kotlin-compiler-embeddable/1.7.10/909803167c986
06fcf22b4c848647c68e351d48d/kotlin-compiler-embeddable-1.7.10.jar:/root/.gradle/caches/modules-2/files-2.1/org.jetbrains.kotlin/kotlin-reflect/1.7.10/165e600dfea6185cf5efa700756294cc4904dbeb/kotlin-reflect-1.7.10.jar:/root/.gradle/caches/modules-2/files-2.1/org.jetbrains.kotlin/kotlin-stdlib/1.7.10/d2abf9e77736ac
c4450dc4a3f707fa2c10f5099d/kotlin-stdlib-1.7.10.jar:/root/.gradle/caches/modules-2/files-2.1/org.jetbrains.kotlin/kotlin-script-runtime/1.7.10/c99c87a6988d8fd8d5142e9ed5c9f34a7cf561ee/kotlin-script-runtime-1.7.10.jar:/root/.gradle/caches/modules-2/files-2.1/org.jetbrains.kotlin/kotlin-daemon-embeddable/1.7.10/3a9
f7aef7080d3ae63126cbba4f827ed664f32fa/kotlin-daemon-embeddable-1.7.10.jar:/root/.gradle/caches/modules-2/files-2.1/org.jetbrains.intellij.deps/trove4j/1.0.20200330/3afb14d5f9ceb459d724e907a21145e8ff394f02/trove4j-1.0.20200330.jar:/root/.gradle/caches/modules-2/files-2.1/net.java.dev.jna/jna/5.6.0/330f2244e9030119
ab3030fc3fededc86713d9cc/jna-5.6.0.jar:/root/.gradle/caches/modules-2/files-2.1/org.jetbrains.kotlin/kotlin-stdlib-common/1.7.10/bac80c520d0a9e3f3673bc2658c6ed02ef45a76a/kotlin-stdlib-common-1.7.10.jar:/root/.gradle/caches/modules-2/files-2.1/org.jetbrains/annotations/13.0/919f0dfe192fb4e063e7dacadee7f8bb9a2672a9
/annotations-13.0.jar
root 411 241 1 20:17 ? 00:00:19 /opt/hostedtoolcache/Java_Zulu_jdk/11.0.18-10/x64/bin/java -Dfile.encoding=UTF-8 -Duser.country -Duser.language=en -Duser.variant -cp /root/.gradle/caches/modules-2/files-2.1/com.google.devsite/dackka-fat/10.10.12/5e0c3f42dd2a1b638dcbda274bcad90dcc3d11a5/dackka-
fat-10.10.12.jar org.jetbrains.dokka.MainKt /tmp/dackkaArgs2855163529207012510.json -loggingLevel DEBUG
Extended Thread dumps:
CC @owengray-google for visibility