Remove netty BytesReference implementations (#54355)

Elasticsearch has a number of different BytesReference implementations.
These implementations can all implement the interface in different ways
with subtly different behavior and performance characteristics. On the
other-hand, the JVM only represents bytes as an array or a direct byte
buffer. This commit deletes the specialized Netty implementations and
moves to using a generic ByteBuffer reference type. This will allow us
to focus on standardizing performance and behave around a smaller number
of implementations that can be used by all components in Elasticsearch.

modules/transport-netty4/src/main/java/org/elasticsearch/transport/netty4/ByteBufBytesReference.java

@@ -1,104 +0,0 @@
-/*
- * Licensed to Elasticsearch under one or more contributor
- * license agreements. See the NOTICE file distributed with
- * this work for additional information regarding copyright
- * ownership. Elasticsearch licenses this file to you under
- * the Apache License, Version 2.0 (the "License"); you may
- * not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *    http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing,
- * software distributed under the License is distributed on an
- * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
- * KIND, either express or implied.  See the License for the
- * specific language governing permissions and limitations
- * under the License.
- */
-package org.elasticsearch.transport.netty4;
-
-import io.netty.buffer.ByteBuf;
-import org.apache.lucene.util.BytesRef;
-import org.elasticsearch.common.bytes.AbstractBytesReference;
-import org.elasticsearch.common.bytes.BytesReference;
-import org.elasticsearch.common.io.stream.StreamInput;
-
-import java.io.IOException;
-import java.io.OutputStream;
-import java.nio.charset.StandardCharsets;
-
-final class ByteBufBytesReference extends AbstractBytesReference {
-
-    private final ByteBuf buffer;
-    private final int length;
-    private final int offset;
-
-    ByteBufBytesReference(ByteBuf buffer, int length) {
-        this.buffer = buffer;
-        this.length = length;
-        this.offset = buffer.readerIndex();
-        assert length <= buffer.readableBytes() : "length[" + length +"] > " + buffer.readableBytes();
-    }
-
-    @Override
-    public byte get(int index) {
-        return buffer.getByte(offset + index);
-    }
-
-    @Override
-    public int getInt(int index) {
-        return buffer.getInt(offset + index);
-    }
-
-    @Override
-    public int indexOf(byte marker, int from) {
-        final int start = offset + from;
-        return buffer.forEachByte(start, length - start, value -> value != marker);
-    }
-
-    @Override
-    public int length() {
-        return length;
-    }
-
-    @Override
-    public BytesReference slice(int from, int length) {
-        return new ByteBufBytesReference(buffer.slice(offset + from, length), length);
-    }
-
-    @Override
-    public StreamInput streamInput() {
-        return new ByteBufStreamInput(buffer.duplicate(), length);
-    }
-
-    @Override
-    public void writeTo(OutputStream os) throws IOException {
-        buffer.getBytes(offset, os, length);
-    }
-
-    ByteBuf toByteBuf() {
-        return buffer.duplicate();
-    }
-
-    @Override
-    public String utf8ToString() {
-        return buffer.toString(offset, length, StandardCharsets.UTF_8);
-    }
-
-    @Override
-    public BytesRef toBytesRef() {
-        if (buffer.hasArray()) {
-            return new BytesRef(buffer.array(), buffer.arrayOffset() + offset, length);
-        }
-        final byte[] copy = new byte[length];
-        buffer.getBytes(offset, copy);
-        return new BytesRef(copy);
-    }
-
-    @Override
-    public long ramBytesUsed() {
-        return buffer.capacity();
-    }
-
-}

modules/transport-netty4/src/main/java/org/elasticsearch/transport/netty4/Netty4Utils.java

@@ -30,6 +30,7 @@ import org.elasticsearch.common.bytes.BytesArray;
 import org.elasticsearch.common.bytes.BytesReference;
 
 import java.io.IOException;
+import java.nio.ByteBuffer;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Locale;
@@ -80,9 +81,6 @@ public class Netty4Utils {
         if (reference.length() == 0) {
             return Unpooled.EMPTY_BUFFER;
         }
-        if (reference instanceof ByteBufBytesReference) {
-            return ((ByteBufBytesReference) reference).toByteBuf();
-        } else {
         final BytesRefIterator iterator = reference.iterator();
         // usually we have one, two, or three components from the header, the message, and a buffer
         final List<ByteBuf> buffers = new ArrayList<>(3);
@@ -103,7 +101,6 @@ public class Netty4Utils {
             throw new AssertionError("no IO happens here", ex);
         }
     }
-    }
 
     /**
      * Wraps the given ChannelBuffer with a BytesReference
@@ -112,7 +109,9 @@ public class Netty4Utils {
         final int readableBytes = buffer.readableBytes();
         if (readableBytes == 0) {
             return BytesArray.EMPTY;
-        }
+        } else {
-        return new ByteBufBytesReference(buffer, buffer.readableBytes());
+            final ByteBuffer[] byteBuffers = buffer.nioBuffers();
+            return BytesReference.fromByteBuffers(byteBuffers);
+        }
     }
 }

modules/transport-netty4/src/test/java/org/elasticsearch/transport/netty4/ByteBufBytesReferenceTests.java

@@ -1,84 +0,0 @@
-/*
- * Licensed to Elasticsearch under one or more contributor
- * license agreements. See the NOTICE file distributed with
- * this work for additional information regarding copyright
- * ownership. Elasticsearch licenses this file to you under
- * the Apache License, Version 2.0 (the "License"); you may
- * not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *    http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing,
- * software distributed under the License is distributed on an
- * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
- * KIND, either express or implied.  See the License for the
- * specific language governing permissions and limitations
- * under the License.
- */
-package org.elasticsearch.transport.netty4;
-
-import io.netty.buffer.ByteBuf;
-import io.netty.buffer.Unpooled;
-import org.apache.lucene.util.BytesRef;
-import org.elasticsearch.common.bytes.AbstractBytesReferenceTestCase;
-import org.elasticsearch.common.bytes.BytesReference;
-import org.elasticsearch.common.io.stream.ReleasableBytesStreamOutput;
-
-import java.io.IOException;
-
-public class ByteBufBytesReferenceTests extends AbstractBytesReferenceTestCase {
-
-    @Override
-    protected BytesReference newBytesReference(int length) throws IOException {
-        return newBytesReferenceWithOffsetOfZero(length);
-    }
-
-    @Override
-    protected BytesReference newBytesReferenceWithOffsetOfZero(int length) throws IOException {
-        ReleasableBytesStreamOutput out = new ReleasableBytesStreamOutput(length, bigarrays);
-        for (int i = 0; i < length; i++) {
-            out.writeByte((byte) random().nextInt(1 << 8));
-        }
-        assertEquals(out.size(), length);
-        BytesReference ref = out.bytes();
-        assertEquals(ref.length(), length);
-        BytesRef bytesRef = ref.toBytesRef();
-        final ByteBuf buffer = Unpooled.wrappedBuffer(bytesRef.bytes, bytesRef.offset, bytesRef.length);
-        return Netty4Utils.toBytesReference(buffer);
-    }
-
-    public void testSliceOnAdvancedBuffer() throws IOException {
-        BytesReference bytesReference = newBytesReference(randomIntBetween(10, 3 * PAGE_SIZE));
-        BytesRef bytesRef = bytesReference.toBytesRef();
-        ByteBuf channelBuffer = Unpooled.wrappedBuffer(bytesRef.bytes, bytesRef.offset,
-            bytesRef.length);
-        int numBytesToRead = randomIntBetween(1, 5);
-        for (int i = 0; i < numBytesToRead; i++) {
-            channelBuffer.readByte();
-        }
-        BytesReference other = Netty4Utils.toBytesReference(channelBuffer);
-        BytesReference slice = bytesReference.slice(numBytesToRead, bytesReference.length() - numBytesToRead);
-        assertEquals(other, slice);
-        assertEquals(other.slice(3, 1), slice.slice(3, 1));
-    }
-
-    public void testImmutable() throws IOException {
-        BytesReference bytesReference = newBytesReference(randomIntBetween(10, 3 * PAGE_SIZE));
-        BytesRef bytesRef = BytesRef.deepCopyOf(bytesReference.toBytesRef());
-        ByteBuf channelBuffer = Unpooled.wrappedBuffer(bytesRef.bytes, bytesRef.offset,
-            bytesRef.length);
-        ByteBufBytesReference byteBufBytesReference = new ByteBufBytesReference(channelBuffer, bytesRef.length);
-        assertEquals(byteBufBytesReference, bytesReference);
-        channelBuffer.readInt(); // this advances the index of the channel buffer
-        assertEquals(byteBufBytesReference, bytesReference);
-        assertEquals(bytesRef, byteBufBytesReference.toBytesRef());
-
-        BytesRef unicodeBytes = new BytesRef(randomUnicodeOfCodepointLength(100));
-        channelBuffer = Unpooled.wrappedBuffer(unicodeBytes.bytes, unicodeBytes.offset, unicodeBytes.length);
-        byteBufBytesReference = new ByteBufBytesReference(channelBuffer, unicodeBytes.length);
-        String utf8ToString = byteBufBytesReference.utf8ToString();
-        channelBuffer.readInt(); // this advances the index of the channel buffer
-        assertEquals(utf8ToString, byteBufBytesReference.utf8ToString());
-    }
-}

modules/transport-netty4/src/test/java/org/elasticsearch/transport/netty4/Netty4UtilsTests.java

@@ -69,9 +69,7 @@ public class Netty4UtilsTests extends ESTestCase {
         BytesReference ref = getRandomizedBytesReference(randomIntBetween(1, 3 * PAGE_SIZE));
         ByteBuf buffer = Netty4Utils.toByteBuf(ref);
         BytesReference bytesReference = Netty4Utils.toBytesReference(buffer);
-        if (ref instanceof ByteBufBytesReference) {
+        if (AbstractBytesReferenceTestCase.getNumPages(ref) > 1) { // we gather the buffers into a channel buffer
-            assertEquals(buffer, ((ByteBufBytesReference) ref).toByteBuf());
-        } else if (AbstractBytesReferenceTestCase.getNumPages(ref) > 1) { // we gather the buffers into a channel buffer
             assertTrue(buffer instanceof CompositeByteBuf);
         }
         assertArrayEquals(BytesReference.toBytes(ref), BytesReference.toBytes(bytesReference));

plugins/transport-nio/src/main/java/org/elasticsearch/http/nio/ByteBufUtils.java

@@ -23,15 +23,11 @@ import io.netty.buffer.CompositeByteBuf;
 import io.netty.buffer.Unpooled;
 import org.apache.lucene.util.BytesRef;
 import org.apache.lucene.util.BytesRefIterator;
-import org.elasticsearch.common.bytes.AbstractBytesReference;
 import org.elasticsearch.common.bytes.BytesArray;
 import org.elasticsearch.common.bytes.BytesReference;
-import org.elasticsearch.common.io.stream.StreamInput;
 
-import java.io.EOFException;
 import java.io.IOException;
-import java.io.OutputStream;
+import java.nio.ByteBuffer;
-import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -45,9 +41,6 @@ class ByteBufUtils {
         if (reference.length() == 0) {
             return Unpooled.EMPTY_BUFFER;
         }
-        if (reference instanceof ByteBufBytesReference) {
-            return ((ByteBufBytesReference) reference).toByteBuf();
-        } else {
         final BytesRefIterator iterator = reference.iterator();
         // usually we have one, two, or three components from the header, the message, and a buffer
         final List<ByteBuf> buffers = new ArrayList<>(3);
@@ -68,243 +61,14 @@ class ByteBufUtils {
             throw new AssertionError("no IO happens here", ex);
         }
     }
-    }
 
     static BytesReference toBytesReference(final ByteBuf buffer) {
         final int readableBytes = buffer.readableBytes();
-        return readableBytes == 0 ? BytesArray.EMPTY : new ByteBufBytesReference(buffer, readableBytes);
+        if (readableBytes == 0) {
-    }
+            return BytesArray.EMPTY;
-
-    private static class ByteBufBytesReference extends AbstractBytesReference {
-
-        private final ByteBuf buffer;
-        private final int length;
-        private final int offset;
-
-        ByteBufBytesReference(ByteBuf buffer, int length) {
-            this.buffer = buffer;
-            this.length = length;
-            this.offset = buffer.readerIndex();
-            assert length <= buffer.readableBytes() : "length[" + length +"] > " + buffer.readableBytes();
-        }
-
-        @Override
-        public byte get(int index) {
-            return buffer.getByte(offset + index);
-        }
-
-        @Override
-        public int getInt(int index) {
-            return buffer.getInt(offset + index);
-        }
-
-        @Override
-        public int indexOf(byte marker, int from) {
-            final int start = offset + from;
-            return buffer.forEachByte(start, length - start, value -> value != marker);
-        }
-
-        @Override
-        public int length() {
-            return length;
-        }
-
-        @Override
-        public BytesReference slice(int from, int length) {
-            return new ByteBufBytesReference(buffer.slice(offset + from, length), length);
-        }
-
-        @Override
-        public StreamInput streamInput() {
-            return new ByteBufStreamInput(buffer.duplicate(), length);
-        }
-
-        @Override
-        public void writeTo(OutputStream os) throws IOException {
-            buffer.getBytes(offset, os, length);
-        }
-
-        ByteBuf toByteBuf() {
-            return buffer.duplicate();
-        }
-
-        @Override
-        public String utf8ToString() {
-            return buffer.toString(offset, length, StandardCharsets.UTF_8);
-        }
-
-        @Override
-        public BytesRef toBytesRef() {
-            if (buffer.hasArray()) {
-                return new BytesRef(buffer.array(), buffer.arrayOffset() + offset, length);
-            }
-            final byte[] copy = new byte[length];
-            buffer.getBytes(offset, copy);
-            return new BytesRef(copy);
-        }
-
-        @Override
-        public long ramBytesUsed() {
-            return buffer.capacity();
-        }
-
-    }
-
-    private static class ByteBufStreamInput extends StreamInput {
-
-        private final ByteBuf buffer;
-        private final int endIndex;
-
-        ByteBufStreamInput(ByteBuf buffer, int length) {
-            if (length > buffer.readableBytes()) {
-                throw new IndexOutOfBoundsException();
-            }
-            this.buffer = buffer;
-            int startIndex = buffer.readerIndex();
-            endIndex = startIndex + length;
-            buffer.markReaderIndex();
-        }
-
-        @Override
-        public BytesReference readBytesReference(int length) throws IOException {
-            // NOTE: It is unsafe to share a reference of the internal structure, so we
-            // use the default implementation which will copy the bytes. It is unsafe because
-            // a netty ByteBuf might be pooled which requires a manual release to prevent
-            // memory leaks.
-            return super.readBytesReference(length);
-        }
-
-        @Override
-        public BytesRef readBytesRef(int length) throws IOException {
-            // NOTE: It is unsafe to share a reference of the internal structure, so we
-            // use the default implementation which will copy the bytes. It is unsafe because
-            // a netty ByteBuf might be pooled which requires a manual release to prevent
-            // memory leaks.
-            return super.readBytesRef(length);
-        }
-
-        @Override
-        public int available() throws IOException {
-            return endIndex - buffer.readerIndex();
-        }
-
-        @Override
-        protected void ensureCanReadBytes(int length) throws EOFException {
-            int bytesAvailable = endIndex - buffer.readerIndex();
-            if (bytesAvailable < length) {
-                throw new EOFException("tried to read: " + length + " bytes but only " + bytesAvailable + " remaining");
-            }
-        }
-
-        @Override
-        public void mark(int readlimit) {
-            buffer.markReaderIndex();
-        }
-
-        @Override
-        public boolean markSupported() {
-            return true;
-        }
-
-        @Override
-        public int read() throws IOException {
-            if (available() == 0) {
-                return -1;
-            }
-            return buffer.readByte() & 0xff;
-        }
-
-        @Override
-        public int read(byte[] b, int off, int len) throws IOException {
-            if (len == 0) {
-                return 0;
-            }
-            int available = available();
-            if (available == 0) {
-                return -1;
-            }
-
-            len = Math.min(available, len);
-            buffer.readBytes(b, off, len);
-            return len;
-        }
-
-        @Override
-        public short readShort() throws IOException {
-            try {
-                return buffer.readShort();
-            } catch (IndexOutOfBoundsException ex) {
-                EOFException eofException = new EOFException();
-                eofException.initCause(ex);
-                throw eofException;
-            }
-        }
-
-        @Override
-        public int readInt() throws IOException {
-            try {
-                return buffer.readInt();
-            } catch (IndexOutOfBoundsException ex) {
-                EOFException eofException = new EOFException();
-                eofException.initCause(ex);
-                throw eofException;
-            }
-        }
-
-        @Override
-        public long readLong() throws IOException {
-            try {
-                return buffer.readLong();
-            } catch (IndexOutOfBoundsException ex) {
-                EOFException eofException = new EOFException();
-                eofException.initCause(ex);
-                throw eofException;
-            }
-        }
-
-        @Override
-        public void reset() throws IOException {
-            buffer.resetReaderIndex();
-        }
-
-        @Override
-        public long skip(long n) throws IOException {
-            if (n > Integer.MAX_VALUE) {
-                return skipBytes(Integer.MAX_VALUE);
         } else {
-                return skipBytes((int) n);
+            final ByteBuffer[] byteBuffers = buffer.nioBuffers();
-            }
+            return BytesReference.fromByteBuffers(byteBuffers);
-        }
-
-        public int skipBytes(int n) throws IOException {
-            int nBytes = Math.min(available(), n);
-            buffer.skipBytes(nBytes);
-            return nBytes;
-        }
-
-
-        @Override
-        public byte readByte() throws IOException {
-            try {
-                return buffer.readByte();
-            } catch (IndexOutOfBoundsException ex) {
-                EOFException eofException = new EOFException();
-                eofException.initCause(ex);
-                throw eofException;
-            }
-        }
-
-        @Override
-        public void readBytes(byte[] b, int offset, int len) throws IOException {
-            int read = read(b, offset, len);
-            if (read < len) {
-                throw new IndexOutOfBoundsException();
-            }
-        }
-
-        @Override
-        public void close() throws IOException {
-            // nothing to do here
         }
     }
 }

server/src/main/java/org/elasticsearch/common/bytes/ByteBufferReference.java

@@ -51,6 +51,25 @@ public class ByteBufferReference extends AbstractBytesReference {
         return buffer.getInt(index);
     }
 
+    @Override
+    public int indexOf(byte marker, int from) {
+        final int remainingBytes = Math.max(length - from, 0);
+        FutureObjects.checkFromIndexSize(from, remainingBytes, length);
+        if (buffer.hasArray()) {
+            int startIndex = from + buffer.arrayOffset();
+            int endIndex = startIndex + remainingBytes;
+            final byte[] array = buffer.array();
+            for (int i = startIndex; i < endIndex; i++) {
+                if (array[i] == marker) {
+                    return (i - buffer.arrayOffset());
+                }
+            }
+            return -1;
+        } else {
+            return super.indexOf(marker, from);
+        }
+    }
+
     @Override
     public int length() {
         return length;

server/src/main/java/org/elasticsearch/common/bytes/CompositeBytesReference.java

@@ -71,6 +71,34 @@ public final class CompositeBytesReference extends AbstractBytesReference {
         return references[i].get(index - offsets[i]);
     }
 
+    @Override
+    public int indexOf(byte marker, int from) {
+        final int remainingBytes = Math.max(length - from, 0);
+        FutureObjects.checkFromIndexSize(from, remainingBytes, length);
+
+        int result = -1;
+        if (length == 0) {
+            return result;
+        }
+
+        final int firstReferenceIndex = getOffsetIndex(from);
+        for (int i = firstReferenceIndex; i < references.length; ++i) {
+            final BytesReference reference = references[i];
+            final int internalFrom;
+            if (i == firstReferenceIndex) {
+                internalFrom = from - offsets[firstReferenceIndex];
+            } else {
+                internalFrom = 0;
+            }
+            result = reference.indexOf(marker, internalFrom);
+            if (result != -1) {
+                result += offsets[i];
+                break;
+            }
+        }
+        return result;
+    }
+
     @Override
     public int length() {
         return length;