Greatly reduce BenchmarkState overhead (62e5fea8) · Commits · e / os / android_frameworks_base

apct-tests/perftests/core/src/java/lang/perftests/SystemPerfTest.java

+6 −0

Original line number	Diff line number	Diff line
		@@ -37,4 +37,10 @@ public class SystemPerfTest {
		System.nanoTime();
		}
		}

		@Test
		public void testBenchmarkOverhead() {
		BenchmarkState state = mPerfStatusReporter.getBenchmarkState();
		while (state.keepRunning()) {}
		}
		}

apct-tests/perftests/multiuser/src/android/multiuser/UserLifecycleTest.java

+1 −4

Original line number	Diff line number	Diff line
		@@ -57,8 +57,6 @@ import java.util.concurrent.TimeUnit;
		@LargeTest
		@RunWith(AndroidJUnit4.class)
		public class UserLifecycleTest {
		private final int MIN_REPEAT_TIMES = 4;

		private final int TIMEOUT_REMOVE_USER_MS = 4 * 1000; // 4 sec
		private final int CHECK_USER_REMOVED_INTERVAL_MS = 200; // 0.2 sec

		@@ -90,7 +88,6 @@ public class UserLifecycleTest {
		mAm = context.getSystemService(ActivityManager.class);
		mIam = ActivityManagerNative.getDefault();
		mState = mPerfStatusReporter.getBenchmarkState();
		mState.setMinRepeatTimes(MIN_REPEAT_TIMES);
		mUsersToRemove = new ArrayList<>();
		}

apct-tests/perftests/utils/src/android/perftests/utils/BenchmarkState.java

+91 −37

Original line number	Diff line number	Diff line
		@@ -23,6 +23,7 @@ import android.util.Log;

		import java.util.ArrayList;
		import java.util.Collections;
		import java.util.concurrent.TimeUnit;

		/**
		* Provides a benchmark framework.
		@@ -41,39 +42,47 @@ import java.util.Collections;
		* System.out.println(state.summaryLine());
		* }
		*/
		public class BenchmarkState {
		public final class BenchmarkState {
		private static final String TAG = "BenchmarkState";

		private static final int NOT_STARTED = 1; // The benchmark has not started yet.
		private static final int NOT_STARTED = 0; // The benchmark has not started yet.
		private static final int WARMUP = 1; // The benchmark is warming up.
		private static final int RUNNING = 2; // The benchmark is running.
		private static final int RUNNING_PAUSED = 3; // The benchmark is temporary paused.
		private static final int FINISHED = 4; // The benchmark has stopped.

		private int mState = NOT_STARTED; // Current benchmark state.

		private long mNanoPreviousTime = 0; // Previously captured System.nanoTime().
		private long mNanoFinishTime = 0; // Finish if System.nanoTime() returns after than this value.
		private long mNanoPausedTime = 0; // The System.nanoTime() when the pauseTiming() is called.
		private long mNanoPausedDuration = 0; // The duration of paused state in nano sec.
		private long mNanoTimeLimit = 1 * 1000 * 1000 * 1000; // 1 sec. Default time limit.
		private static final long WARMUP_DURATION_NS = ms2ns(250); // warm-up for at least 250ms
		private static final int WARMUP_MIN_ITERATIONS = 16; // minimum iterations to warm-up for

		// TODO: Tune these values.
		private static final long TARGET_TEST_DURATION_NS = ms2ns(500); // target testing for 500 ms
		private static final int MAX_TEST_ITERATIONS = 1000000;
		private static final int MIN_TEST_ITERATIONS = 100;
		private static final int REPEAT_COUNT = 5;

		private long mStartTimeNs = 0; // Previously captured System.nanoTime().
		private long mPausedTimeNs = 0; // The System.nanoTime() when the pauseTiming() is called.
		private long mPausedDurationNs = 0; // The duration of paused state in nano sec.

		private int mIteration = 0;
		private int mMaxIterations = 0;

		private int mRepeatCount = 0;

		// Statistics. These values will be filled when the benchmark has finished.
		// The computation needs double precision, but long int is fine for final reporting.
		private long mMedian = 0;
		private double mMean = 0.0;
		private double mStandardDeviation = 0.0;

		// Number of iterations needed for calculating the stats.
		private int mMinRepeatTimes = 16;
		private long mMin = 0;

		// Individual duration in nano seconds.
		private ArrayList<Long> mResults = new ArrayList<>();

		/**
		* Sets the number of iterations needed for calculating the stats. Default is 16.
		*/
		public void setMinRepeatTimes(int minRepeatTimes) {
		mMinRepeatTimes = minRepeatTimes;
		private static final long ms2ns(long ms) {
		return TimeUnit.MILLISECONDS.toNanos(ms);
		}

		/**
		@@ -89,8 +98,13 @@ public class BenchmarkState {
		mMedian = size % 2 == 0 ? (mResults.get(size / 2) + mResults.get(size / 2 + 1)) / 2 :
		mResults.get(size / 2);

		mMin = mResults.get(0);
		for (int i = 0; i < size; ++i) {
		mMean += mResults.get(i);
		long result = mResults.get(i);
		mMean += result;
		if (result < mMin) {
		mMin = result;
		}
		}
		mMean /= (double) size;

		@@ -108,7 +122,7 @@ public class BenchmarkState {
		throw new IllegalStateException(
		"Unable to pause the benchmark. The benchmark has already paused.");
		}
		mNanoPausedTime = System.nanoTime();
		mPausedTimeNs = System.nanoTime();
		mState = RUNNING_PAUSED;
		}

		@@ -119,9 +133,41 @@ public class BenchmarkState {
		throw new IllegalStateException(
		"Unable to resume the benchmark. The benchmark is already running.");
		}
		mNanoPausedDuration += System.nanoTime() - mNanoPausedTime;
		mNanoPausedTime = 0;
		mPausedDurationNs += System.nanoTime() - mPausedTimeNs;
		mPausedTimeNs = 0;
		mState = RUNNING;
		}

		private void beginWarmup() {
		mStartTimeNs = System.nanoTime();
		mIteration = 0;
		mState = WARMUP;
		}

		private void beginBenchmark(long warmupDuration, int iterations) {
		mMaxIterations = (int) (TARGET_TEST_DURATION_NS / (warmupDuration / iterations));
		mMaxIterations = Math.min(MAX_TEST_ITERATIONS,
		Math.max(mMaxIterations, MIN_TEST_ITERATIONS));
		mPausedDurationNs = 0;
		mIteration = 0;
		mRepeatCount = 0;
		mState = RUNNING;
		mStartTimeNs = System.nanoTime();
		}

		private boolean startNextTestRun() {
		final long currentTime = System.nanoTime();
		mResults.add((currentTime - mStartTimeNs - mPausedDurationNs) / mMaxIterations);
		mRepeatCount++;
		if (mRepeatCount >= REPEAT_COUNT) {
		calculateSatistics();
		mState = FINISHED;
		return false;
		}
		mPausedDurationNs = 0;
		mIteration = 0;
		mStartTimeNs = System.nanoTime();
		return true;
		}

		/**
		@@ -132,23 +178,22 @@ public class BenchmarkState {
		public boolean keepRunning() {
		switch (mState) {
		case NOT_STARTED:
		mNanoPreviousTime = System.nanoTime();
		mNanoFinishTime = mNanoPreviousTime + mNanoTimeLimit;
		mState = RUNNING;
		beginWarmup();
		return true;
		case WARMUP:
		mIteration++;
		// Only check nanoTime on every iteration in WARMUP since we
		// don't yet have a target iteration count.
		final long duration = System.nanoTime() - mStartTimeNs;
		if (mIteration >= WARMUP_MIN_ITERATIONS && duration >= WARMUP_DURATION_NS) {
		beginBenchmark(duration, mIteration);
		}
		return true;
		case RUNNING:
		final long currentTime = System.nanoTime();
		mResults.add(currentTime - mNanoPreviousTime - mNanoPausedDuration);
		mNanoPausedDuration = 0;

		// To calculate statistics, needs two or more samples.
		if (mResults.size() > mMinRepeatTimes && currentTime > mNanoFinishTime) {
		calculateSatistics();
		mState = FINISHED;
		return false;
		mIteration++;
		if (mIteration >= mMaxIterations) {
		return startNextTestRun();
		}

		mNanoPreviousTime = currentTime;
		return true;
		case RUNNING_PAUSED:
		throw new IllegalStateException(
		@@ -161,21 +206,28 @@ public class BenchmarkState {
		}
		}

		public long mean() {
		private long mean() {
		if (mState != FINISHED) {
		throw new IllegalStateException("The benchmark hasn't finished");
		}
		return (long) mMean;
		}

		public long median() {
		private long median() {
		if (mState != FINISHED) {
		throw new IllegalStateException("The benchmark hasn't finished");
		}
		return mMedian;
		}

		public long standardDeviation() {
		private long min() {
		if (mState != FINISHED) {
		throw new IllegalStateException("The benchmark hasn't finished");
		}
		return mMin;
		}

		private long standardDeviation() {
		if (mState != FINISHED) {
		throw new IllegalStateException("The benchmark hasn't finished");
		}
		@@ -187,10 +239,11 @@ public class BenchmarkState {
		sb.append("Summary: ");
		sb.append("median=").append(median()).append("ns, ");
		sb.append("mean=").append(mean()).append("ns, ");
		sb.append("min=").append(min()).append("ns, ");
		sb.append("sigma=").append(standardDeviation()).append(", ");
		sb.append("iteration=").append(mResults.size()).append(", ");
		// print out the first few iterations' number for double checking.
		int sampleNumber = Math.min(mResults.size(), mMinRepeatTimes);
		int sampleNumber = Math.min(mResults.size(), 16);
		for (int i = 0; i < sampleNumber; i++) {
		sb.append("No ").append(i).append(" result is ").append(mResults.get(i)).append(", ");
		}
		@@ -202,6 +255,7 @@ public class BenchmarkState {
		Bundle status = new Bundle();
		status.putLong(key + "_median", median());
		status.putLong(key + "_mean", mean());
		status.putLong(key + "_min", min());
		status.putLong(key + "_standardDeviation", standardDeviation());
		instrumentation.sendStatus(Activity.RESULT_OK, status);
		}