如何应用Kotlin Compiler 2并结合Gradle 1.8.+提升构建速度？

Why K2 Compiler Didn't Show Improvement #

Kotlin Compiler 2 (K2) is an experimental feature introduced in Kotlin 1.9.0. Your current setup uses Kotlin Gradle Plugin 1.8.10, which has no official support for K2—enabling the experimental flag here won't actually activate the K2 compiler, hence no speed difference. To leverage K2, you need to upgrade to Kotlin 1.9.0 or later, paired with a compatible Android Gradle Plugin (AGP) version.

Feasible Build Speed Improvement Steps #

1. Upgrade to Compatible Toolchain Versions #

• Kotlin Gradle Plugin: Upgrade to 1.9.0+ (e.g., 1.9.20) to access K2 and latest compilation optimizations.
• Android Gradle Plugin: Pair Kotlin 1.9+ with AGP 8.0+ (e.g., 8.2.0) for better compatibility and build performance.
• Gradle Wrapper: Use Gradle 8.x (matching AGP's required Gradle version) to benefit from Gradle's latest build cache and configuration optimizations.

2. Enable Gradle's Core Optimization Features #

Add these settings to your gradle.properties file:

# Enable build cache (reuses outputs from previous builds)
org.gradle.caching=true

# Enable configuration cache (speeds up build configuration phase)
org.gradle.configuration-cache=true
org.gradle.configuration-cache.problems=warn

# Increase JVM heap size for Gradle daemon
org.gradle.jvmargs=-Xmx4096m -XX:MaxMetaspaceSize=1024m -XX:+HeapDumpOnOutOfMemoryError -Dfile.encoding=UTF-8

# Enable parallel execution of independent tasks
org.gradle.parallel=true

# Enable daemon mode (keeps Gradle running in background)
org.gradle.daemon=true

3. Optimize Kotlin Compilation #

• Incremental Compilation: Ensure it's enabled (default for Kotlin 1.3+), verify in your module-level build.gradle.kts:

  tasks.withType<KotlinCompile> {
      kotlinOptions.incremental = true
  }
  

• Use K2 Compiler (After Upgrade): Once on Kotlin 1.9+, enable K2 globally in gradle.properties:

  kotlin.experimental.tryK2=true
  

  (No need for the task-level configuration you added earlier.)

4. Reduce Unnecessary Build Work #

• Disable Unused Build Variants: Filter out non-debug/release variants in your module build.gradle.kts:

  android {
      variantFilter { variant ->
          val buildType = variant.buildType?.name
          if (buildType != "debug" && buildType != "release") {
              setIgnore(true)
          }
      }
  }
  

• Skip Lint for Debug Builds: Avoid lint checks during debug builds to save time:

  android {
      lint {
          checkReleaseBuilds false
          abortOnError false
      }
  }
  

5. Module and Dependency Optimization #

• Split Large Modules: Break monolithic modules into smaller, focused feature modules to reduce compilation scope.
• Dependency Locking: Lock dependencies to avoid repeated resolution on every build:

  dependencyLocking {
      lockAllConfigurations()
  }
  

• Trim Transitive Dependencies: Use exclude to remove unused transitive dependencies where possible.

6. Environment Tweaks #

• Use an SSD for faster file access (Gradle builds are I/O-intensive).
• Close unnecessary background applications to free up CPU and memory resources.

内容的提问来源于stack exchange，提问作者c-an