androidx.benchmark.junit4

Kotlin |Java

Classes

`AndroidBenchmarkRunner`	Instrumentation runner for benchmarks, used to increase stability of measurements and minimize interference.
`BenchmarkRule`	JUnit rule for benchmarking code on an Android device.
`BenchmarkRule.Scope`	Handle used for controlling measurement during `measureRepeated`.
`PerfettoTraceRule`	Add this rule to record a Perfetto trace for each test on Android Lollipop (API 21)+ devices.

Extension functions summary

`inline Unit`	`BenchmarkRule.measureRepeated(crossinline block: BenchmarkRule.Scope.() -> Unit)` Benchmark a block of code.
`inline Unit`	`BenchmarkRule.measureRepeatedOnMainThread(crossinline block: BenchmarkRule.Scope.() -> Unit)` Benchmark a block of code, which runs on the main thread, and can safely interact with UI.

Extension functions

measureRepeated

Artifact: androidx.benchmark:benchmark-junit4

View Source

Added in 1.0.0

inline fun BenchmarkRule.measureRepeated(crossinline block: BenchmarkRule.Scope.() -> Unit): Unit

Benchmark a block of code.

import androidx.benchmark.junit4.BenchmarkRule
import androidx.benchmark.junit4.measureRepeated
import androidx.test.ext.junit.runners.AndroidJUnit4

@RunWith(AndroidJUnit4::class)
class MyBenchmark {
    @get:Rule val benchmarkRule = BenchmarkRule()

    @Test
    fun measureWork() {
        benchmarkRule.measureRepeated { doSomeWork() }
    }
}

Parameters
`crossinline block: BenchmarkRule.Scope.() -> Unit`	The block of code to benchmark.

measureRepeatedOnMainThread

Artifact: androidx.benchmark:benchmark-junit4

View Source

Added in 1.3.0

inline fun BenchmarkRule.measureRepeatedOnMainThread(crossinline block: BenchmarkRule.Scope.() -> Unit): Unit

Benchmark a block of code, which runs on the main thread, and can safely interact with UI.

While @UiThreadRule works for a standard test, it doesn't work for benchmarks of arbitrary duration, as they may run for much more than 5 seconds and suffer ANRs, especially in continuous runs.

import androidx.benchmark.junit4.BenchmarkRule
import androidx.benchmark.junit4.measureRepeated
import androidx.benchmark.junit4.measureRepeatedOnMainThread
import androidx.test.ext.junit.runners.AndroidJUnit4

@RunWith(AndroidJUnit4::class)
class MainThreadBenchmark {
    @get:Rule val benchmarkRule = BenchmarkRule()

    @Test
    fun measureWork() {
        benchmarkRule.measureRepeatedOnMainThread {
            // this block is run on the main thread
            doSomeWorkOnMainThread()
        }
    }
}

Parameters
`crossinline block: BenchmarkRule.Scope.() -> Unit`	The block of code to benchmark.

Throws
`java.lang.Throwable`	when an exception is thrown on the main thread.
`kotlin.IllegalStateException`	if a hard deadline is exceeded while the block is running on the main thread.