Merge "Cache least recently used output buffer." (6eb27ef9) · Commits · e / os / android_frameworks_base

apct-tests/perftests/core/src/com/android/internal/util/FastDataPerfTest.java

+7 −3

Original line number	Original line	Diff line number	Diff line
	@@ -64,9 +64,13 @@ public class FastDataPerfTest {
	final BenchmarkState state = mPerfStatusReporter.getBenchmarkState();		final BenchmarkState state = mPerfStatusReporter.getBenchmarkState();
	while (state.keepRunning()) {		while (state.keepRunning()) {
	os.reset();		os.reset();
	final FastDataOutput out = new FastDataOutput(os, BUFFER_SIZE);		final FastDataOutput out = FastDataOutput.obtain(os);
			try {
	doWrite(out);		doWrite(out);
	out.flush();		out.flush();
			} finally {
			out.release();
			}
	}		}
	}		}

core/java/com/android/internal/util/BinaryXmlSerializer.java

+7 −2

Original line number	Original line	Diff line number	Diff line
	@@ -124,7 +124,7 @@ public final class BinaryXmlSerializer implements TypedXmlSerializer {
	throw new UnsupportedOperationException();		throw new UnsupportedOperationException();
	}		}

	mOut = new FastDataOutput(os, BUFFER_SIZE);		mOut = FastDataOutput.obtain(os);
	mOut.write(PROTOCOL_MAGIC_VERSION_0);		mOut.write(PROTOCOL_MAGIC_VERSION_0);

	mTagCount = 0;		mTagCount = 0;
	@@ -138,8 +138,10 @@ public final class BinaryXmlSerializer implements TypedXmlSerializer {

	@Override		@Override
	public void flush() throws IOException {		public void flush() throws IOException {
			if (mOut != null) {
	mOut.flush();		mOut.flush();
	}		}
			}

	@Override		@Override
	public void startDocument(@Nullable String encoding, @Nullable Boolean standalone)		public void startDocument(@Nullable String encoding, @Nullable Boolean standalone)
	@@ -157,6 +159,9 @@ public final class BinaryXmlSerializer implements TypedXmlSerializer {
	public void endDocument() throws IOException {		public void endDocument() throws IOException {
	mOut.writeByte(END_DOCUMENT \| TYPE_NULL);		mOut.writeByte(END_DOCUMENT \| TYPE_NULL);
	flush();		flush();

			mOut.release();
			mOut = null;
	}		}

	@Override		@Override

core/java/com/android/internal/util/FastDataOutput.java

+50 −3

Original line number	Original line	Diff line number	Diff line
	@@ -30,6 +30,7 @@ import java.io.IOException;
	import java.io.OutputStream;		import java.io.OutputStream;
	import java.util.HashMap;		import java.util.HashMap;
	import java.util.Objects;		import java.util.Objects;
			import java.util.concurrent.atomic.AtomicReference;

	/**		/**
	* Optimized implementation of {@link DataOutput} which buffers data in memory		* Optimized implementation of {@link DataOutput} which buffers data in memory
	@@ -41,23 +42,26 @@ import java.util.Objects;
	public class FastDataOutput implements DataOutput, Flushable, Closeable {		public class FastDataOutput implements DataOutput, Flushable, Closeable {
	private static final int MAX_UNSIGNED_SHORT = 65_535;		private static final int MAX_UNSIGNED_SHORT = 65_535;

			private static final int BUFFER_SIZE = 32_768;

			private static AtomicReference<FastDataOutput> sOutCache = new AtomicReference<>();

	private final VMRuntime mRuntime;		private final VMRuntime mRuntime;
	private final OutputStream mOut;

	private final byte[] mBuffer;		private final byte[] mBuffer;
	private final long mBufferPtr;		private final long mBufferPtr;
	private final int mBufferCap;		private final int mBufferCap;

			private OutputStream mOut;
	private int mBufferPos;		private int mBufferPos;

	/**		/**
	* Values that have been "interned" by {@link #writeInternedUTF(String)}.		* Values that have been "interned" by {@link #writeInternedUTF(String)}.
	*/		*/
	private HashMap<String, Short> mStringRefs = new HashMap<>();		private final HashMap<String, Short> mStringRefs = new HashMap<>();

	public FastDataOutput(@NonNull OutputStream out, int bufferSize) {		public FastDataOutput(@NonNull OutputStream out, int bufferSize) {
	mRuntime = VMRuntime.getRuntime();		mRuntime = VMRuntime.getRuntime();
	mOut = Objects.requireNonNull(out);
	if (bufferSize < 8) {		if (bufferSize < 8) {
	throw new IllegalArgumentException();		throw new IllegalArgumentException();
	}		}
	@@ -65,6 +69,48 @@ public class FastDataOutput implements DataOutput, Flushable, Closeable {
	mBuffer = (byte[]) mRuntime.newNonMovableArray(byte.class, bufferSize);		mBuffer = (byte[]) mRuntime.newNonMovableArray(byte.class, bufferSize);
	mBufferPtr = mRuntime.addressOf(mBuffer);		mBufferPtr = mRuntime.addressOf(mBuffer);
	mBufferCap = mBuffer.length;		mBufferCap = mBuffer.length;

			setOutput(out);
			}

			/**
			* Create a new FastDataOutput object or retrieve one from cache.
			*/
			public static FastDataOutput obtain(@NonNull OutputStream out) {
			FastDataOutput instance = sOutCache.getAndSet(null);
			if (instance != null) {
			instance.setOutput(out);
			return instance;
			}
			return new FastDataOutput(out, BUFFER_SIZE);
			}

			/**
			* Put a FastDataOutput object back into the cache.
			* You must not touch the object after this call.
			*/
			public void release() {
			if (mBufferPos > 0) {
			throw new IllegalStateException("Lingering data, call flush() before releasing.");
			}

			mOut = null;
			mBufferPos = 0;
			mStringRefs.clear();

			if (mBufferCap == BUFFER_SIZE) {
			// Try to return to the cache.
			sOutCache.compareAndSet(null, this);
			}
			}

			/**
			* Re-initializes the object for the new output.
			*/
			private void setOutput(@NonNull OutputStream out) {
			mOut = Objects.requireNonNull(out);
			mBufferPos = 0;
			mStringRefs.clear();
	}		}

	private void drain() throws IOException {		private void drain() throws IOException {
	@@ -83,6 +129,7 @@ public class FastDataOutput implements DataOutput, Flushable, Closeable {
	@Override		@Override
	public void close() throws IOException {		public void close() throws IOException {
	mOut.close();		mOut.close();
			release();
	}		}

	@Override		@Override