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author | Marcelo Vanzin <vanzin@cloudera.com> | 2015-04-01 16:06:11 -0700 |
---|---|---|
committer | Reynold Xin <rxin@databricks.com> | 2015-04-01 16:06:11 -0700 |
commit | f084c5de14eb10a6aba82a39e03e7877926ebb9e (patch) | |
tree | 6a874a0f19171c3f6c68e4de07fa8ae7ac85c260 | |
parent | fb25e8c7f45b4f96561e3f7434a0f4dfce8ddefe (diff) | |
download | spark-f084c5de14eb10a6aba82a39e03e7877926ebb9e.tar.gz spark-f084c5de14eb10a6aba82a39e03e7877926ebb9e.tar.bz2 spark-f084c5de14eb10a6aba82a39e03e7877926ebb9e.zip |
[SPARK-6578] [core] Fix thread-safety issue in outbound path of network library.
While the inbound path of a netty pipeline is thread-safe, the outbound
path is not. That means that multiple threads can compete to write messages
to the next stage of the pipeline.
The network library sometimes breaks a single RPC message into multiple
buffers internally to avoid copying data (see MessageEncoder). This can
result in the following scenario (where "FxBy" means "frame x, buffer y"):
T1 F1B1 F1B2
\ \
\ \
socket F1B1 F2B1 F1B2 F2B2
/ /
/ /
T2 F2B1 F2B2
And the frames now cannot be rebuilt on the receiving side because the
different messages have been mixed up on the wire.
The fix wraps these multi-buffer messages into a `FileRegion` object
so that these messages are written "atomically" to the next pipeline handler.
Author: Marcelo Vanzin <vanzin@cloudera.com>
Closes #5234 from vanzin/SPARK-6578 and squashes the following commits:
16b2d70 [Marcelo Vanzin] Forgot to update a type.
c9c2e4e [Marcelo Vanzin] Review comments: simplify some code.
9c888ac [Marcelo Vanzin] Small style nits.
8474bab [Marcelo Vanzin] Fix multiple calls to MessageWithHeader.transferTo().
e26509f [Marcelo Vanzin] Merge branch 'master' into SPARK-6578
c503f6c [Marcelo Vanzin] Implement a custom FileRegion instead of using locks.
84aa7ce [Marcelo Vanzin] Rename handler to the correct name.
432f3bd [Marcelo Vanzin] Remove unneeded method.
8d70e60 [Marcelo Vanzin] Fix thread-safety issue in outbound path of network library.
7 files changed, 364 insertions, 10 deletions
diff --git a/network/common/pom.xml b/network/common/pom.xml index 7b51845206..22c738bde6 100644 --- a/network/common/pom.xml +++ b/network/common/pom.xml @@ -80,6 +80,11 @@ <artifactId>mockito-all</artifactId> <scope>test</scope> </dependency> + <dependency> + <groupId>org.slf4j</groupId> + <artifactId>slf4j-log4j12</artifactId> + <scope>test</scope> + </dependency> </dependencies> <build> diff --git a/network/common/src/main/java/org/apache/spark/network/protocol/MessageEncoder.java b/network/common/src/main/java/org/apache/spark/network/protocol/MessageEncoder.java index 91d1e8a538..0f999f5dfe 100644 --- a/network/common/src/main/java/org/apache/spark/network/protocol/MessageEncoder.java +++ b/network/common/src/main/java/org/apache/spark/network/protocol/MessageEncoder.java @@ -72,9 +72,11 @@ public final class MessageEncoder extends MessageToMessageEncoder<Message> { in.encode(header); assert header.writableBytes() == 0; - out.add(header); if (body != null && bodyLength > 0) { - out.add(body); + out.add(new MessageWithHeader(header, body, bodyLength)); + } else { + out.add(header); } } + } diff --git a/network/common/src/main/java/org/apache/spark/network/protocol/MessageWithHeader.java b/network/common/src/main/java/org/apache/spark/network/protocol/MessageWithHeader.java new file mode 100644 index 0000000000..215a8517e8 --- /dev/null +++ b/network/common/src/main/java/org/apache/spark/network/protocol/MessageWithHeader.java @@ -0,0 +1,106 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF 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.apache.spark.network.protocol; + +import java.io.IOException; +import java.nio.channels.WritableByteChannel; + +import com.google.common.base.Preconditions; +import com.google.common.primitives.Ints; +import io.netty.buffer.ByteBuf; +import io.netty.channel.FileRegion; +import io.netty.util.AbstractReferenceCounted; +import io.netty.util.ReferenceCountUtil; + +/** + * A wrapper message that holds two separate pieces (a header and a body) to avoid + * copying the body's content. + */ +class MessageWithHeader extends AbstractReferenceCounted implements FileRegion { + + private final ByteBuf header; + private final int headerLength; + private final Object body; + private final long bodyLength; + private long totalBytesTransferred; + + MessageWithHeader(ByteBuf header, Object body, long bodyLength) { + Preconditions.checkArgument(body instanceof ByteBuf || body instanceof FileRegion, + "Body must be a ByteBuf or a FileRegion."); + this.header = header; + this.headerLength = header.readableBytes(); + this.body = body; + this.bodyLength = bodyLength; + } + + @Override + public long count() { + return headerLength + bodyLength; + } + + @Override + public long position() { + return 0; + } + + @Override + public long transfered() { + return totalBytesTransferred; + } + + @Override + public long transferTo(WritableByteChannel target, long position) throws IOException { + Preconditions.checkArgument(position == totalBytesTransferred, "Invalid position."); + long written = 0; + + if (position < headerLength) { + written += copyByteBuf(header, target); + if (header.readableBytes() > 0) { + totalBytesTransferred += written; + return written; + } + } + + if (body instanceof FileRegion) { + // Adjust the position. If the write is happening as part of the same call where the header + // (or some part of it) is written, `position` will be less than the header size, so we want + // to start from position 0 in the FileRegion object. Otherwise, we start from the position + // requested by the caller. + long bodyPos = position > headerLength ? position - headerLength : 0; + written += ((FileRegion)body).transferTo(target, bodyPos); + } else if (body instanceof ByteBuf) { + written += copyByteBuf((ByteBuf) body, target); + } + + totalBytesTransferred += written; + return written; + } + + @Override + protected void deallocate() { + header.release(); + ReferenceCountUtil.release(body); + } + + private int copyByteBuf(ByteBuf buf, WritableByteChannel target) throws IOException { + int written = target.write(buf.nioBuffer()); + buf.skipBytes(written); + return written; + } + +} diff --git a/network/common/src/test/java/org/apache/spark/network/ByteArrayWritableChannel.java b/network/common/src/test/java/org/apache/spark/network/ByteArrayWritableChannel.java new file mode 100644 index 0000000000..b525ed69fc --- /dev/null +++ b/network/common/src/test/java/org/apache/spark/network/ByteArrayWritableChannel.java @@ -0,0 +1,55 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF 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.apache.spark.network; + +import java.nio.ByteBuffer; +import java.nio.channels.WritableByteChannel; + +public class ByteArrayWritableChannel implements WritableByteChannel { + + private final byte[] data; + private int offset; + + public ByteArrayWritableChannel(int size) { + this.data = new byte[size]; + this.offset = 0; + } + + public byte[] getData() { + return data; + } + + @Override + public int write(ByteBuffer src) { + int available = src.remaining(); + src.get(data, offset, available); + offset += available; + return available; + } + + @Override + public void close() { + + } + + @Override + public boolean isOpen() { + return true; + } + +} diff --git a/network/common/src/test/java/org/apache/spark/network/ProtocolSuite.java b/network/common/src/test/java/org/apache/spark/network/ProtocolSuite.java index 43dc0cf8c7..860dd6d9b3 100644 --- a/network/common/src/test/java/org/apache/spark/network/ProtocolSuite.java +++ b/network/common/src/test/java/org/apache/spark/network/ProtocolSuite.java @@ -17,26 +17,34 @@ package org.apache.spark.network; +import java.util.List; + +import com.google.common.primitives.Ints; +import io.netty.buffer.Unpooled; +import io.netty.channel.ChannelHandlerContext; +import io.netty.channel.FileRegion; import io.netty.channel.embedded.EmbeddedChannel; +import io.netty.handler.codec.MessageToMessageEncoder; import org.junit.Test; import static org.junit.Assert.assertEquals; -import org.apache.spark.network.protocol.Message; -import org.apache.spark.network.protocol.StreamChunkId; -import org.apache.spark.network.protocol.ChunkFetchRequest; import org.apache.spark.network.protocol.ChunkFetchFailure; +import org.apache.spark.network.protocol.ChunkFetchRequest; import org.apache.spark.network.protocol.ChunkFetchSuccess; -import org.apache.spark.network.protocol.RpcRequest; -import org.apache.spark.network.protocol.RpcFailure; -import org.apache.spark.network.protocol.RpcResponse; +import org.apache.spark.network.protocol.Message; import org.apache.spark.network.protocol.MessageDecoder; import org.apache.spark.network.protocol.MessageEncoder; +import org.apache.spark.network.protocol.RpcFailure; +import org.apache.spark.network.protocol.RpcRequest; +import org.apache.spark.network.protocol.RpcResponse; +import org.apache.spark.network.protocol.StreamChunkId; import org.apache.spark.network.util.NettyUtils; public class ProtocolSuite { private void testServerToClient(Message msg) { - EmbeddedChannel serverChannel = new EmbeddedChannel(new MessageEncoder()); + EmbeddedChannel serverChannel = new EmbeddedChannel(new FileRegionEncoder(), + new MessageEncoder()); serverChannel.writeOutbound(msg); EmbeddedChannel clientChannel = new EmbeddedChannel( @@ -51,7 +59,8 @@ public class ProtocolSuite { } private void testClientToServer(Message msg) { - EmbeddedChannel clientChannel = new EmbeddedChannel(new MessageEncoder()); + EmbeddedChannel clientChannel = new EmbeddedChannel(new FileRegionEncoder(), + new MessageEncoder()); clientChannel.writeOutbound(msg); EmbeddedChannel serverChannel = new EmbeddedChannel( @@ -83,4 +92,25 @@ public class ProtocolSuite { testServerToClient(new RpcFailure(0, "this is an error")); testServerToClient(new RpcFailure(0, "")); } + + /** + * Handler to transform a FileRegion into a byte buffer. EmbeddedChannel doesn't actually transfer + * bytes, but messages, so this is needed so that the frame decoder on the receiving side can + * understand what MessageWithHeader actually contains. + */ + private static class FileRegionEncoder extends MessageToMessageEncoder<FileRegion> { + + @Override + public void encode(ChannelHandlerContext ctx, FileRegion in, List<Object> out) + throws Exception { + + ByteArrayWritableChannel channel = new ByteArrayWritableChannel(Ints.checkedCast(in.count())); + while (in.transfered() < in.count()) { + in.transferTo(channel, in.transfered()); + } + out.add(Unpooled.wrappedBuffer(channel.getData())); + } + + } + } diff --git a/network/common/src/test/java/org/apache/spark/network/protocol/MessageWithHeaderSuite.java b/network/common/src/test/java/org/apache/spark/network/protocol/MessageWithHeaderSuite.java new file mode 100644 index 0000000000..ff985096d7 --- /dev/null +++ b/network/common/src/test/java/org/apache/spark/network/protocol/MessageWithHeaderSuite.java @@ -0,0 +1,129 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF 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.apache.spark.network.protocol; + +import java.io.IOException; +import java.nio.ByteBuffer; +import java.nio.channels.WritableByteChannel; + +import io.netty.buffer.ByteBuf; +import io.netty.buffer.Unpooled; +import io.netty.channel.FileRegion; +import io.netty.util.AbstractReferenceCounted; +import org.junit.Test; + +import static org.junit.Assert.*; + +import org.apache.spark.network.ByteArrayWritableChannel; + +public class MessageWithHeaderSuite { + + @Test + public void testSingleWrite() throws Exception { + testFileRegionBody(8, 8); + } + + @Test + public void testShortWrite() throws Exception { + testFileRegionBody(8, 1); + } + + @Test + public void testByteBufBody() throws Exception { + ByteBuf header = Unpooled.copyLong(42); + ByteBuf body = Unpooled.copyLong(84); + MessageWithHeader msg = new MessageWithHeader(header, body, body.readableBytes()); + + ByteBuf result = doWrite(msg, 1); + assertEquals(msg.count(), result.readableBytes()); + assertEquals(42, result.readLong()); + assertEquals(84, result.readLong()); + } + + private void testFileRegionBody(int totalWrites, int writesPerCall) throws Exception { + ByteBuf header = Unpooled.copyLong(42); + int headerLength = header.readableBytes(); + TestFileRegion region = new TestFileRegion(totalWrites, writesPerCall); + MessageWithHeader msg = new MessageWithHeader(header, region, region.count()); + + ByteBuf result = doWrite(msg, totalWrites / writesPerCall); + assertEquals(headerLength + region.count(), result.readableBytes()); + assertEquals(42, result.readLong()); + for (long i = 0; i < 8; i++) { + assertEquals(i, result.readLong()); + } + } + + private ByteBuf doWrite(MessageWithHeader msg, int minExpectedWrites) throws Exception { + int writes = 0; + ByteArrayWritableChannel channel = new ByteArrayWritableChannel((int) msg.count()); + while (msg.transfered() < msg.count()) { + msg.transferTo(channel, msg.transfered()); + writes++; + } + assertTrue("Not enough writes!", minExpectedWrites <= writes); + return Unpooled.wrappedBuffer(channel.getData()); + } + + private static class TestFileRegion extends AbstractReferenceCounted implements FileRegion { + + private final int writeCount; + private final int writesPerCall; + private int written; + + TestFileRegion(int totalWrites, int writesPerCall) { + this.writeCount = totalWrites; + this.writesPerCall = writesPerCall; + } + + @Override + public long count() { + return 8 * writeCount; + } + + @Override + public long position() { + return 0; + } + + @Override + public long transfered() { + return 8 * written; + } + + @Override + public long transferTo(WritableByteChannel target, long position) throws IOException { + for (int i = 0; i < writesPerCall; i++) { + ByteBuf buf = Unpooled.copyLong((position / 8) + i); + ByteBuffer nio = buf.nioBuffer(); + while (nio.remaining() > 0) { + target.write(nio); + } + buf.release(); + written++; + } + return 8 * writesPerCall; + } + + @Override + protected void deallocate() { + } + + } + +} diff --git a/network/common/src/test/resources/log4j.properties b/network/common/src/test/resources/log4j.properties new file mode 100644 index 0000000000..e8da774f7c --- /dev/null +++ b/network/common/src/test/resources/log4j.properties @@ -0,0 +1,27 @@ +# +# Licensed to the Apache Software Foundation (ASF) under one or more +# contributor license agreements. See the NOTICE file distributed with +# this work for additional information regarding copyright ownership. +# The ASF 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. +# + +# Set everything to be logged to the file target/unit-tests.log +log4j.rootCategory=DEBUG, file +log4j.appender.file=org.apache.log4j.FileAppender +log4j.appender.file.append=true +log4j.appender.file.file=target/unit-tests.log +log4j.appender.file.layout=org.apache.log4j.PatternLayout +log4j.appender.file.layout.ConversionPattern=%d{yy/MM/dd HH:mm:ss.SSS} %t %p %c{1}: %m%n + +# Silence verbose logs from 3rd-party libraries. +log4j.logger.io.netty=INFO |