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Benchmarks

Purpose: Generates a release baseline profile and compares cold-start timings with and without it. The configured generation device is a Gradle Managed Device; these tasks are not automatically run by the current CI workflows.

Key APIs

API What it does
BaselineProfileGenerator BaselineProfileRule that presses Home, starts the activity and waits for idle; no in-app screen journey
StartupBenchmark MacrobenchmarkRule comparing timeToInitialDisplayMs with CompilationMode.None() vs. Partial(baselineProfileMode = Require) 
// benchmarks/src/main/kotlin/dev/atick/benchmarks/BaselineProfileGenerator.kt
@Test
fun generate() = baselineProfileRule.collect(
    packageName = PACKAGE_NAME,
    includeInStartupProfile = true,
) {
    pressHome()
    startActivityAndWait()
    device.waitForIdle()
}

Gotchas

  • Regenerate with ./gradlew :app:generateReleaseBaselineProfile. Generation is not automatic during app builds. Add representative interaction journeys when extending the app.
  • Run only the comparison class with:
./gradlew :benchmarks:pixel6Api33BenchmarkReleaseAndroidTest -Pandroid.testInstrumentationRunnerArguments.class=dev.atick.benchmarks.StartupBenchmark
  • These tasks boot an emulator and require its SDK image and virtualization. Compare timeToInitialDisplayMs between compilation modes; improvement is not guaranteed. Use a physical device for representative timing. The build guide lists generated profiles and result locations.