Fast and reliable builds with Gradle and Maven

Having fast and reliable builds has a major influence on developer productivity. Faster builds make feedback cycles shorter by reducing wait times and context switches for developers. If a build is unreliable, developers may re-run the same build over and over again and when that fails, run a clean build and/or clear all the caches. Doing so removes many of the performance optimizations of the build tool, forcing every step of the build to be recomputed which takes much longer than an incremental build.

In this session, we will show you how Gradle Enterprise can be used for both Gradle and Maven to make builds faster and more reliable through build caching and build scans, respectively. The build cache, very different from the m2 cache, stores the outputs of each step of the build on a remote server. These cached outputs can then be used by both developer and CI builds. We’ll also dive into ways to increase the speed and reliability of each step of the build using build scans. Build scans provide insights into where bottlenecks occur and provide the data to optimize problems specific to your build.

Transcript

1. Fast and reliable builds with
   Gradle and Maven
   Marc Philipp (@marcphilipp), Gradle Inc.
   1
   

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2. About me
   speaker {
   name = "Marc Philipp"
   home = "Karlsruhe, Germany"
   company = "Gradle Inc."
   title = "Senior Software Engineer"
   openSourceRoles = [
   "JUnit team lead"
   ]
   twitter = "@marcphilipp"
   github = "marcphilipp"
   web = uri("https://www.marcphilipp.de")
   }
   2 . 1
   

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3. Gradle Inc.
   Build Happiness
   Products
   Gradle Build Tool
   Gradle Enterprise
   2 . 2
   

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4. How do builds affect
   developer produc vity?
   failures: about 20% of builds fail due to code defects
   5‑10% of a team’s capacity is spent on fixing
   slowness: a team’s capacity is reduced by 4% for
   each extra minute of build me
   unreliability: 5% of a team’s capacity goes into
   debugging build problems
   2 . 3
   

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5. Fast builds
   3 . 1
   

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6. Fast builds
   faster = avoid doing needless work
   reuse results!
   incremental builds
   build cache
   3 . 2
   

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7. Incremental builds
   Gradle
   Maven
   3 . 3
   

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8. Incremental builds
   Gradle can reuse results
   of the last me
   this build ran
   on this machine.
   3 . 4
   

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9. We can do be er!
   3 . 5
   

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10. Why not…
    of any me
    and any build
    that ran anywhere.
    3 . 6
    

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11. Even be er
    For Maven and Gradle builds!
    3 . 7
    

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12. 3 . 8
    

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13. Build Cache for Gradle
    $> gradle ­­build­cache assemble
    :compileJava FROM­CACHE
    :processResources
    :classes
    :jar
    :assemble
    BUILD SUCCESSFUL
    3 . 9
    

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14. Build Cache for Gradle
    out‑of‑the‑box for Java, Groovy, Scala, C++ and
    Swi projects
    supports compile, test and verifica on tasks
    high‑performance remote backend from Gradle
    Docker Hub: gradle/build‑cache‑node
    3 . 10
    

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15. Build Cache for Maven
    custom extension (part of Gradle Enterprise)
    ini al release: March 2019
    supported plugins: Java Compiler, Surefire/Failsafe,
    Javadoc, JAXB, Checkstyle
    3 . 11
    

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16. Build Cache – Demo
    3 . 12
    

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17. How does it work?
    Calculate cacheKey of a task/goal from its inputs:
    cacheKey(javaCompile) = hash(sourceFiles, … )
    Store its outputs under cacheEntry:
    cacheEntry(javaCompile) = fileTree(classFiles)
    Gradle task
    Inputs Outputs
    3 . 13
    

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18. Local and remote cache
    3 . 14
    

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19. 3 . 15
    

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20. 3 . 16
    

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21. 3 . 17
    

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22. 3 . 18
    

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23. 3 . 19
    

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24. 3 . 20
    

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25. 3 . 21
    

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26. 3 . 22
    

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27. 3 . 23
    

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28. 3 . 24
    

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29. Reliable builds
    4 . 1
    

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30. Requirements
    monitoring of builds to discover
    regressions/improvements
    both builds by developers and CI
    reliability
    performance
    4 . 2
    

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31. What are Build Scans?
    persistent record of what happened during a build
    permanent and shareable URL
    for developers and build engineers
    4 . 3
    

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32. Gradle
    $> gradle build ­­scan
    ...
    BUILD SUCCESSFUL in 8m 22s
    418 actionable tasks: 112 executed, 48 from cache, 258 up­
    Publishing build scan...
    https://scans.gradle.com/s/lbmn7n4dngqgq
    4 . 4
    

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33. Maven
    (with extension registered in .mvn/extensions.xml)
    $> mvn clean verify
    ...
    [INFO] ­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
    [INFO] BUILD SUCCESS
    [INFO] ­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
    [INFO] Total time: 5.262 s
    [INFO] Finished at: 2019­04­23T09:55:36+02:00
    [INFO] ­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
    [INFO] 13 goals, 8 executed, 5 from cache, saving at least
    [INFO]
    [INFO] Publishing build scan...
    [INFO] https://gradle.com/s/ypgljbvelzxzs
    [INFO]
    4 . 5
    

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34. Build Scans – Demo
    4 . 6
    

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35. Build Scans
    support Gradle and Maven
    public scans are free on
    without build comparison, performance
    dashboard etc.
    Gradle Enterprise provides addi onal features and
    on‑premise hos ng
    scans.gradle.com
    h ps:/
    /scans.gradle.com/s/nq7w6cjm72mak/
    4 . 7
    

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36. Custom analyses
    use Export API
    h ps:/
    /github.com/gradle/build‑analysis‑demo
    4 . 8
    

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37. 4 . 9
    

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38. 4 . 10
    

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39. Resources
    Free trainings on , e.g.
    Build Cache Deep Dive
    Maven + Gradle Enterprise
    Gradle Build Tool:
    Gradle Enterprise:
    h ps:/
    /gradle.com/training/
    YouTube channel
    h ps:/
    /gradle.org
    h ps:/
    /gradle.com
    5 . 1
    

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40. Дякую!
    See you tomorrow?
    5
    From Revolu on to Con nuous Evolu on
    Tomorrow, 16:10, Track C
    News from JUnit 5.x
    5 . 2
    

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