Improving Android Build Performance

We all know a fast build makes for a happy developer. Unfortunately, it’s easy for Android builds get complex and slow. You’ve updated to the latest Android Plugin, but your still waiting more than you like, what do you do?

Recent Gradle releases give you new capabilities to improve your build speed up to an order of magnitude. This session discusses how you can :

* Identify performance bottlenecks with build scans
* Fix common problems like: slow configuration time, tasks running when they shouldn’t, and builds that don’t parallelize well.
* Use Gradle Enterprise to diagnose project-wide issues and keep your newly-performant build performant.

Transcript

1. Improving Android Build Performance Tony Robalik, Gradle Inc.
3. The Cost of Builds (#perfmatters)
4. | X Fast Builds Matter 60s waste * 50 builds per day * 10 developers > 8h wasted per day …and that’s not even considering lost focus https://gradle.com/quantifying-the-costs-of-builds/
5. | X
6. | X
7. | X Fast Builds Matter Don’t even get me started on morale…
8. General Advice
9. | X #science 1. Define scenario to improve 2. Profile scenario 3. Identify biggest bottleneck 4. Fix bottleneck 5. Verify fix by measurement 6. Repeat
10. | X Automate your measurements github.com/gradle/gradle-profiler $ gradle-profiler --benchmark --scenario-file scenarios // Scenario 1 configurationTime { tasks = ["help"] } // Scenario 2 assembleNoCache { tasks = ["clean", “assembleDebug”] gradle-args = ["--no-build-cache"] } // Scenario 3 assembleCache { tasks = ["clean", "assembleDebug"] gradle-args = ["--build-cache"] }
11. | X Automate your measurements github.com/gradle/gradle-profiler $ gradle-profiler --benchmark --scenario-file scenarios // Scenario 1 configurationTime { tasks = ["help"] } // Scenario 2 assembleNoCache { tasks = ["clean", “assembleDebug”] gradle-args = ["--no-build-cache"] } // Scenario 3 assembleCache { tasks = ["clean", "assembleDebug"] gradle-args = ["--build-cache"] }
12. | X Automate your measurements github.com/gradle/gradle-profiler $ gradle-profiler --benchmark --scenario-file scenarios // Scenario 1 configurationTime { tasks = ["help"] } // Scenario 2 assembleNoCache { tasks = ["clean", “assembleDebug”] gradle-args = ["--no-build-cache"] } // Scenario 3 assembleCache { tasks = ["clean", "assembleDebug"] gradle-args = ["--build-cache"] }
13. | X Stay Up-To-Date buildscript { repositories { google() } dependencies { classpath ‘com.android.tools.build:gradle:3.1.4’ } } $ ./gradlew wrapper --gradle-version 4.9
14. | X JVM tuning Provide enough heap space Other tweaks often do more harm than good Spend your time on structural improvements
15. | X JVM tuning Provide enough heap space Other tweaks often do more harm than good Spend your time on structural improvements # The only useful argument org.gradle.jvmargs=-Xmx4g
16. | X JVM tuning
17. Where is the Problem?
18. | X Build Scans
19. | X Build Scans $ ./gradlew assembleDebug --scan
20. | X Build Scans $ ./gradlew assembleDebug --scan
21. | X The Build Lifecycle
22. | X Red Flags Startup/Settings/buildSrc > 1s Single-line change ℳ clean build No-op build doing any work at all High GC time
23. | X Red Flags Startup/Settings/buildSrc > 1s Single-line change ℳ clean build No-op build doing any work at all High GC time
24. | X Red Flags Startup/Settings/buildSrc > 1s Single-line change ℳ clean build No-op build doing any work at all High GC time
25. | X Red Flags Startup/Settings/buildSrc > 1s Single-line change ℳ clean build No-op build doing any work at all High GC time
26. | X Red Flags Startup/Settings/buildSrc > 1s Single-line change ℳ clean build No-op build doing any work at all High GC time
27. Your Build
28. Startup, buildSrc, Settings
29. | X Startup, buildSrc, Settings Use the daemon, keep it healthy
30. | X Startup, buildSrc, Settings Don’t do this // settings.gradle rootDir.listFiles({ File dir, String name -> name.endsWith(“.gradle") } as FilenameFilter) .each { include "$it" } ? ¿
31. | X Startup, buildSrc, Settings Don’t do this // settings.gradle rootDir.listFiles({ File dir, String name -> name.endsWith(“.gradle") } as FilenameFilter) .each { include "$it" }
32. Configuration Time
33. | X Configuration Time Applying plugins Evaluating build scripts Running afterEvaluate {} blocks
34. | X Configuration Time When running any task Even `gradlew help` / `gradlew tasks` Android Studio sync
35. | X Resolution at Configuration Time
36. | X Eager resolution Resolution at Configuration Time task badTask(type: Jar) { from configurations.compile.collect { it.directory ? it : zipTree(it) } classifier “don’t do this” }
37. | X Eager resolution Resolution at Configuration Time task badTask(type: Jar) { from configurations.compile.collect { it.directory ? it : zipTree(it) } classifier “don’t do this” }
38. | X Resolution at Configuration Time task badTask(type: Jar) { from { configurations.compile.collect { it.directory ? it : zipTree(it) } } classifier “don’t do this” } Use lazy evaluation instead
39. | X Inefficient Plugins
40. | X Expensive logic for each project Inefficient Plugins // `version.gradle` def out = new ByteArrayOutputStream() exec { commandLine 'git', 'rev-parse', “HEAD” standardOutput = out workingDir = rootDir } version = new String(out.toByteArray()) // root `build.gradle` subprojects { apply from: "$rootDir/version.gradle" }
41. | X Inefficient Plugins // `version.gradle` as before // root `build.gradle` apply from: "$rootDir/version.gradle" subprojects { version = rootProject.version } Reuse expensive calculations
42. | X Variant Explosion https://developer.android.com/studio/build/build-variants#filter-variants variantFilter { variant -> def flavorName = variant.flavors[0].name def freeFlavor = flavorName == "free" if (!freeFlavor && variant.buildType.name == "release") { variant.ignore = true } }
43. | X Variant Explosion https://developer.android.com/studio/build/build-variants#filter-variants variantFilter { variant -> def flavorName = variant.flavors[0].name def freeFlavor = flavorName == "free" if (!freeFlavor && variant.buildType.name == "release") { variant.ignore = true } }
44. | X Configuration Time Avoid dependency resolution Avoid I/O Don’t repeat yourself
45. Optimizing Build Logic
46. | X Extract Script Plugins apply from: "$rootDir/static_analysis.gradle" apply from: "$rootDir/coverage.gradle" apply from: “$rootDir/spock_android_lib.gradle” apply from: "$rootDir/junit5html.gradle" if (isOnCi()) { // This plugin adds ~5s to every build apply plugin: 'com.getkeepsafe.dexcount' } Makes finding issues easier
47. | X Extract Binary Plugins Use buildSrc Use static compilation Keep build scripts declarative https://docs.gradle.org/current/userguide/organizing_gradle_projects.html#sec:build_sources
48. | X Extract Binary Plugins https://docs.gradle.org/current/userguide/organizing_gradle_projects.html#sec:build_sources $rootDir/buildSrc/ src/main/<java|kotlin|groovy>/ com/yourCompany/ all/the/things/
49. Execution Time
50. | X Execution Time Executing selected tasks Incremental Cacheable Parallelizable
51. | X Execution Time Executing selected tasks Incremental Cacheable Parallelizable
52. | X Execution Time Executing selected tasks Incremental Cacheable Parallelizable
53. | X Execution Time Executing selected tasks Incremental Cacheable Parallelizable
54. | X Incremental Builds Nothing changed? Executed tasks should be zero!
55. | X Incremental Builds Nothing changed? Executed tasks should be zero!
56. | X Incremental Builds Find volatile inputs
57. | X Incremental Builds android { defaultConfig { versionName “4.0.0-${new Date()}” } }
58. | X Example: Crashlytics Unique IDs are the bane of local dev performance
59. | X Example: Crashlytics Unique IDs are the bane of local dev performance apply plugin: 'io.fabric' android { buildTypes { debug { ext.alwaysUpdateBuildId = false } } }
60. | X Faster Compilation Modularization => Compile avoidance Decoupled code => Faster incremental compilation Careful with Kotlin annotation processing (for now)
61. | X Faster Compilation Modularization => Compile avoidance Decoupled code => Faster incremental compilation Careful with Kotlin annotation processing (for now)
62. | X Faster Compilation Modularization => Compile avoidance Decoupled code => Faster incremental compilation Careful with Kotlin annotation processing (for now)
63. | X Faster Compilation Modularization => Compile avoidance Decoupled code => Faster incremental compilation Careful with Kotlin annotation processing (for now)
64. | X Incremental Annotation Processing Since Gradle 4.7 Early adopters: Lombok & Android-State Others: github.com/gradle/gradle/issues/5277
65. | X Incremental Annotation Processing Since Gradle 4.7 Early adopters: Lombok & Android-State Others: github.com/gradle/gradle/issues/5277
66. | X Caching https://guides.gradle.org/using-build-cache/
67. | X Caching https://guides.gradle.org/using-build-cache/ Many tasks are cacheable
68. | X https://developer.android.com/studio/build/build-cache Save time for your whole team with one or more remote caches https://guides.gradle.org/using-build-cache/ Caching
69. | X Parallelism --parallel # Or in gradle.properties org.gradle.parallel=true
70. | X Parallelism Serial execution
71. | X Parallelism --parallel and small, decoupled projects
72. Keeping track of performance
73. | X Gradle Enterprise
74. | X See all Builds Find out what colleagues are struggling with
75. | X Detailed Performance Profile
76. | X Watch Performance over Time
77. | X Watch Performance over Time
78. Resources
79. | X Gradle performance guide https://guides.gradle.org/performance Android performance guide https://developer.android.com/studio/build/optimize-your-build.html Plugin development guide https://guides.gradle.org/implementing-gradle-plugins Structuring build logic guide https://docs.gradle.org/current/userguide/organizing_build_logic.html Guides
80. | X scans.gradle.com
81. w Thank you droidcon NYC 2018 tony@gradle.com @autonomousapps