Merge "Add sharding to Binder Latency collection and make it configurable. The... (34c549c7) · Commits · e / os / android_frameworks_base

core/java/com/android/internal/os/BinderCallsStats.java

+6 −1

Original line number	Diff line number	Diff line
		@@ -1105,9 +1105,11 @@ public class BinderCallsStats implements BinderInternal.Observer {
		public static final String SETTINGS_MAX_CALL_STATS_KEY = "max_call_stats_count";
		public static final String SETTINGS_IGNORE_BATTERY_STATUS_KEY = "ignore_battery_status";
		// Settings for BinderLatencyObserver.
		public static final String SETTINGS_COLLECT_LATENCY_DATA_KEY = "collect_Latency_data";
		public static final String SETTINGS_COLLECT_LATENCY_DATA_KEY = "collect_latency_data";
		public static final String SETTINGS_LATENCY_OBSERVER_SAMPLING_INTERVAL_KEY =
		"latency_observer_sampling_interval";
		public static final String SETTINGS_LATENCY_OBSERVER_SHARDING_MODULO_KEY =
		"latency_observer_sharding_modulo";
		public static final String SETTINGS_LATENCY_OBSERVER_PUSH_INTERVAL_MINUTES_KEY =
		"latency_observer_push_interval_minutes";
		public static final String SETTINGS_LATENCY_HISTOGRAM_BUCKET_COUNT_KEY =
		@@ -1187,6 +1189,9 @@ public class BinderCallsStats implements BinderInternal.Observer {
		binderLatencyObserver.setSamplingInterval(mParser.getInt(
		SETTINGS_LATENCY_OBSERVER_SAMPLING_INTERVAL_KEY,
		BinderLatencyObserver.PERIODIC_SAMPLING_INTERVAL_DEFAULT));
		binderLatencyObserver.setShardingModulo(mParser.getInt(
		SETTINGS_LATENCY_OBSERVER_SHARDING_MODULO_KEY,
		BinderLatencyObserver.SHARDING_MODULO_DEFAULT));
		binderLatencyObserver.setHistogramBucketsParams(
		mParser.getInt(
		SETTINGS_LATENCY_HISTOGRAM_BUCKET_COUNT_KEY,

core/java/com/android/internal/os/BinderLatencyObserver.java

+42 −4

Original line number	Diff line number	Diff line
		@@ -44,6 +44,7 @@ public class BinderLatencyObserver {

		// Latency observer parameters.
		public static final int PERIODIC_SAMPLING_INTERVAL_DEFAULT = 10;
		public static final int SHARDING_MODULO_DEFAULT = 1;
		public static final int STATSD_PUSH_INTERVAL_MINUTES_DEFAULT = 360;

		// Histogram buckets parameters.
		@@ -58,6 +59,11 @@ public class BinderLatencyObserver {
		// Sampling period to control how often to track CPU usage. 1 means all calls, 100 means ~1 out
		// of 100 requests.
		private int mPeriodicSamplingInterval = PERIODIC_SAMPLING_INTERVAL_DEFAULT;
		// Controls how many APIs will be collected per device. 1 means all APIs, 10 means every 10th
		// API will be collected.
		private int mShardingModulo = SHARDING_MODULO_DEFAULT;
		// Controls which shards will be collected on this device.
		private int mShardingOffset;

		private int mBucketCount = BUCKET_COUNT_DEFAULT;
		private int mFirstBucketSize = FIRST_BUCKET_SIZE_DEFAULT;
		@@ -156,7 +162,7 @@ public class BinderLatencyObserver {
		FrameworkStatsLog.BINDER_LATENCY_REPORTED,
		atom.getBytes(),
		mPeriodicSamplingInterval,
		1,
		mShardingModulo,
		mBucketCount,
		mFirstBucketSize,
		mBucketScaleFactor);
		@@ -185,6 +191,7 @@ public class BinderLatencyObserver {
		mLatencyBuckets = new BinderLatencyBuckets(
		mBucketCount, mFirstBucketSize, mBucketScaleFactor);
		mProcessSource = processSource;
		mShardingOffset = mRandom.nextInt(mShardingModulo);
		noteLatencyDelayed();
		}

		@@ -194,7 +201,12 @@ public class BinderLatencyObserver {
		return;
		}

		LatencyDims dims = new LatencyDims(s.binderClass, s.transactionCode);
		LatencyDims dims = LatencyDims.create(s.binderClass, s.transactionCode);

		if (!shouldCollect(dims)) {
		return;
		}

		long elapsedTimeMicro = getElapsedRealtimeMicro();
		long callDuration = elapsedTimeMicro - s.timeStarted;

		@@ -220,6 +232,10 @@ public class BinderLatencyObserver {
		return SystemClock.elapsedRealtimeNanos() / 1000;
		}

		protected boolean shouldCollect(LatencyDims dims) {
		return (dims.hashCode() + mShardingOffset) % mShardingModulo == 0;
		}

		protected boolean shouldKeepSample() {
		return mRandom.nextInt() % mPeriodicSamplingInterval == 0;
		}
		@@ -240,6 +256,23 @@ public class BinderLatencyObserver {
		}
		}

		/** Updates the sharding modulo. */
		public void setShardingModulo(int shardingModulo) {
		if (shardingModulo <= 0) {
		Slog.w(TAG, "Ignored invalid sharding modulo (value must be positive): "
		+ shardingModulo);
		return;
		}

		synchronized (mLock) {
		if (shardingModulo != mShardingModulo) {
		mShardingModulo = shardingModulo;
		mShardingOffset = mRandom.nextInt(shardingModulo);
		reset();
		}
		}
		}

		/** Updates the statsd push interval. */
		public void setPushInterval(int pushIntervalMinutes) {
		if (pushIntervalMinutes <= 0) {
		@@ -289,7 +322,12 @@ public class BinderLatencyObserver {
		// Cached hash code, 0 if not set yet.
		private int mHashCode = 0;

		public LatencyDims(Class<? extends Binder> binderClass, int transactionCode) {
		/** Creates a new instance of LatencyDims. */
		public static LatencyDims create(Class<? extends Binder> binderClass, int transactionCode) {
		return new LatencyDims(binderClass, transactionCode);
		}

		private LatencyDims(Class<? extends Binder> binderClass, int transactionCode) {
		this.mBinderClass = binderClass;
		this.mTransactionCode = transactionCode;
		}
		@@ -317,7 +355,7 @@ public class BinderLatencyObserver {
		return mHashCode;
		}
		int hash = mTransactionCode;
		hash = 31 * hash + mBinderClass.hashCode();
		hash = 31 * hash + mBinderClass.getName().hashCode();
		mHashCode = hash;
		return hash;
		}

core/tests/coretests/src/com/android/internal/os/BinderLatencyObserverTest.java

+64 −4

Original line number	Diff line number	Diff line
		@@ -41,6 +41,7 @@ import org.junit.runner.RunWith;

		import java.util.ArrayList;
		import java.util.Arrays;
		import java.util.Iterator;
		import java.util.Random;

		@SmallTest
		@@ -71,9 +72,9 @@ public class BinderLatencyObserverTest {

		ArrayMap<LatencyDims, int[]> latencyHistograms = blo.getLatencyHistograms();
		assertEquals(2, latencyHistograms.keySet().size());
		assertThat(latencyHistograms.get(new LatencyDims(binder.getClass(), 1)))
		assertThat(latencyHistograms.get(LatencyDims.create(binder.getClass(), 1)))
		.asList().containsExactly(2, 0, 1, 0, 0).inOrder();
		assertThat(latencyHistograms.get(new LatencyDims(binder.getClass(), 2)))
		assertThat(latencyHistograms.get(LatencyDims.create(binder.getClass(), 2)))
		.asList().containsExactly(0, 0, 0, 0, 2).inOrder();
		}

		@@ -115,7 +116,7 @@ public class BinderLatencyObserverTest {

		// The long call should be capped to maxint (to not overflow) and placed in the last bucket.
		assertThat(blo.getLatencyHistograms()
		.get(new LatencyDims(binder.getClass(), 1)))
		.get(LatencyDims.create(binder.getClass(), 1)))
		.asList().containsExactly(0, 0, 0, 0, 1)
		.inOrder();
		}
		@@ -132,7 +133,7 @@ public class BinderLatencyObserverTest {
		blo.setElapsedTime(2);
		blo.callEnded(callSession);

		LatencyDims dims = new LatencyDims(binder.getClass(), 1);
		LatencyDims dims = LatencyDims.create(binder.getClass(), 1);
		// Fill the buckets with maxint.
		Arrays.fill(blo.getLatencyHistograms().get(dims), Integer.MAX_VALUE);
		assertThat(blo.getLatencyHistograms().get(dims))
		@@ -240,6 +241,61 @@ public class BinderLatencyObserverTest {
		.inOrder();
		}

		@Test
		public void testSharding() {
		TestBinderLatencyObserver blo = new TestBinderLatencyObserver();
		blo.setShardingModulo(2);
		blo.setHistogramBucketsParams(5, 5, 1.125f);

		Binder binder = new Binder();
		CallSession callSession = new CallSession();
		callSession.binderClass = binder.getClass();
		callSession.transactionCode = 1;
		blo.setElapsedTime(2);
		blo.callEnded(callSession);
		callSession.transactionCode = 2;
		blo.setElapsedTime(4);
		blo.callEnded(callSession);
		callSession.transactionCode = 3;
		blo.setElapsedTime(2);
		blo.callEnded(callSession);
		callSession.transactionCode = 4;
		blo.setElapsedTime(4);
		blo.callEnded(callSession);

		ArrayMap<LatencyDims, int[]> latencyHistograms = blo.getLatencyHistograms();
		Iterator<LatencyDims> iterator = latencyHistograms.keySet().iterator();
		LatencyDims dims;

		// Hash codes are not consistent per device and not mockable so the test needs to consider
		// whether the hashCode of LatencyDims is odd or even and test accordingly.
		if (LatencyDims.create(binder.getClass(), 0).hashCode() % 2 == 0) {
		assertEquals(2, latencyHistograms.size());
		dims = iterator.next();
		assertEquals(binder.getClass(), dims.getBinderClass());
		assertEquals(1, dims.getTransactionCode());
		assertThat(latencyHistograms.get(dims)).asList().containsExactly(1, 0, 0, 0, 0)
		.inOrder();
		dims = iterator.next();
		assertEquals(binder.getClass(), dims.getBinderClass());
		assertEquals(3, dims.getTransactionCode());
		assertThat(latencyHistograms.get(dims)).asList().containsExactly(1, 0, 0, 0, 0)
		.inOrder();
		} else {
		assertEquals(2, latencyHistograms.size());
		dims = iterator.next();
		assertEquals(binder.getClass(), dims.getBinderClass());
		assertEquals(2, dims.getTransactionCode());
		assertThat(latencyHistograms.get(dims)).asList().containsExactly(1, 0, 0, 0, 0)
		.inOrder();
		dims = iterator.next();
		assertEquals(binder.getClass(), dims.getBinderClass());
		assertEquals(4, dims.getTransactionCode());
		assertThat(latencyHistograms.get(dims)).asList().containsExactly(1, 0, 0, 0, 0)
		.inOrder();
		}
		}

		public static class TestBinderLatencyObserver extends BinderLatencyObserver {
		private long mElapsedTime = 0;
		private ArrayList<String> mWrittenAtoms;
		@@ -259,6 +315,10 @@ public class BinderLatencyObserverTest {
		public int nextInt() {
		return mCallCount++;
		}

		public int nextInt(int x) {
		return 1;
		}
		};
		}
		},