merge in master

Author: holdenk

core/pom.xml

@@ -361,6 +361,16 @@
       <artifactId>junit</artifactId>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>org.hamcrest</groupId>
+      <artifactId>hamcrest-core</artifactId>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.hamcrest</groupId>
+      <artifactId>hamcrest-library</artifactId>
+      <scope>test</scope>
+    </dependency>
     <dependency>
       <groupId>com.novocode</groupId>
       <artifactId>junit-interface</artifactId>

core/src/main/java/org/apache/spark/shuffle/unsafe/DummySerializerInstance.java

@@ -0,0 +1,93 @@
+/*
+ * 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.shuffle.unsafe;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.nio.ByteBuffer;
+
+import scala.reflect.ClassTag;
+
+import org.apache.spark.serializer.DeserializationStream;
+import org.apache.spark.serializer.SerializationStream;
+import org.apache.spark.serializer.SerializerInstance;
+import org.apache.spark.unsafe.PlatformDependent;
+
+/**
+ * Unfortunately, we need a serializer instance in order to construct a DiskBlockObjectWriter.
+ * Our shuffle write path doesn't actually use this serializer (since we end up calling the
+ * `write() OutputStream methods), but DiskBlockObjectWriter still calls some methods on it. To work
+ * around this, we pass a dummy no-op serializer.
+ */
+final class DummySerializerInstance extends SerializerInstance {
+
+  public static final DummySerializerInstance INSTANCE = new DummySerializerInstance();
+
+  private DummySerializerInstance() { }
+
+  @Override
+  public SerializationStream serializeStream(final OutputStream s) {
+    return new SerializationStream() {
+      @Override
+      public void flush() {
+        // Need to implement this because DiskObjectWriter uses it to flush the compression stream
+        try {
+          s.flush();
+        } catch (IOException e) {
+          PlatformDependent.throwException(e);
+        }
+      }
+
+      @Override
+      public <T> SerializationStream writeObject(T t, ClassTag<T> ev1) {
+        throw new UnsupportedOperationException();
+      }
+
+      @Override
+      public void close() {
+        // Need to implement this because DiskObjectWriter uses it to close the compression stream
+        try {
+          s.close();
+        } catch (IOException e) {
+          PlatformDependent.throwException(e);
+        }
+      }
+    };
+  }
+
+  @Override
+  public <T> ByteBuffer serialize(T t, ClassTag<T> ev1) {
+    throw new UnsupportedOperationException();
+  }
+
+  @Override
+  public DeserializationStream deserializeStream(InputStream s) {
+    throw new UnsupportedOperationException();
+  }
+
+  @Override
+  public <T> T deserialize(ByteBuffer bytes, ClassLoader loader, ClassTag<T> ev1) {
+    throw new UnsupportedOperationException();
+  }
+
+  @Override
+  public <T> T deserialize(ByteBuffer bytes, ClassTag<T> ev1) {
+    throw new UnsupportedOperationException();
+  }
+}

core/src/main/java/org/apache/spark/shuffle/unsafe/PackedRecordPointer.java

@@ -0,0 +1,92 @@
+/*
+ * 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.shuffle.unsafe;
+
+/**
+ * Wrapper around an 8-byte word that holds a 24-bit partition number and 40-bit record pointer.
+ * <p>
+ * Within the long, the data is laid out as follows:
+ * <pre>
+ *   [24 bit partition number][13 bit memory page number][27 bit offset in page]
+ * </pre>
+ * This implies that the maximum addressable page size is 2^27 bits = 128 megabytes, assuming that
+ * our offsets in pages are not 8-byte-word-aligned. Since we have 2^13 pages (based off the
+ * 13-bit page numbers assigned by {@link org.apache.spark.unsafe.memory.TaskMemoryManager}), this
+ * implies that we can address 2^13 * 128 megabytes = 1 terabyte of RAM per task.
+ * <p>
+ * Assuming word-alignment would allow for a 1 gigabyte maximum page size, but we leave this
+ * optimization to future work as it will require more careful design to ensure that addresses are
+ * properly aligned (e.g. by padding records).
+ */
+final class PackedRecordPointer {
+
+  static final int MAXIMUM_PAGE_SIZE_BYTES = 1 << 27;  // 128 megabytes
+
+  /**
+   * The maximum partition identifier that can be encoded. Note that partition ids start from 0.
+   */
+  static final int MAXIMUM_PARTITION_ID = (1 << 24) - 1;  // 16777215
+
+  /** Bit mask for the lower 40 bits of a long. */
+  private static final long MASK_LONG_LOWER_40_BITS = (1L << 40) - 1;
+
+  /** Bit mask for the upper 24 bits of a long */
+  private static final long MASK_LONG_UPPER_24_BITS = ~MASK_LONG_LOWER_40_BITS;
+
+  /** Bit mask for the lower 27 bits of a long. */
+  private static final long MASK_LONG_LOWER_27_BITS = (1L << 27) - 1;
+
+  /** Bit mask for the lower 51 bits of a long. */
+  private static final long MASK_LONG_LOWER_51_BITS = (1L << 51) - 1;
+
+  /** Bit mask for the upper 13 bits of a long */
+  private static final long MASK_LONG_UPPER_13_BITS = ~MASK_LONG_LOWER_51_BITS;
+
+  /**
+   * Pack a record address and partition id into a single word.
+   *
+   * @param recordPointer a record pointer encoded by TaskMemoryManager.
+   * @param partitionId a shuffle partition id (maximum value of 2^24).
+   * @return a packed pointer that can be decoded using the {@link PackedRecordPointer} class.
+   */
+  public static long packPointer(long recordPointer, int partitionId) {
+    assert (partitionId <= MAXIMUM_PARTITION_ID);
+    // Note that without word alignment we can address 2^27 bytes = 128 megabytes per page.
+    // Also note that this relies on some internals of how TaskMemoryManager encodes its addresses.
+    final long pageNumber = (recordPointer & MASK_LONG_UPPER_13_BITS) >>> 24;
+    final long compressedAddress = pageNumber | (recordPointer & MASK_LONG_LOWER_27_BITS);
+    return (((long) partitionId) << 40) | compressedAddress;
+  }
+
+  private long packedRecordPointer;
+
+  public void set(long packedRecordPointer) {
+    this.packedRecordPointer = packedRecordPointer;
+  }
+
+  public int getPartitionId() {
+    return (int) ((packedRecordPointer & MASK_LONG_UPPER_24_BITS) >>> 40);
+  }
+
+  public long getRecordPointer() {
+    final long pageNumber = (packedRecordPointer << 24) & MASK_LONG_UPPER_13_BITS;
+    final long offsetInPage = packedRecordPointer & MASK_LONG_LOWER_27_BITS;
+    return pageNumber | offsetInPage;
+  }
+
+}

core/src/main/java/org/apache/spark/shuffle/unsafe/SpillInfo.java

@@ -0,0 +1,37 @@
+/*
+ * 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.shuffle.unsafe;
+
+import java.io.File;
+
+import org.apache.spark.storage.TempShuffleBlockId;
+
+/**
+ * Metadata for a block of data written by {@link UnsafeShuffleExternalSorter}.
+ */
+final class SpillInfo {
+  final long[] partitionLengths;
+  final File file;
+  final TempShuffleBlockId blockId;
+
+  public SpillInfo(int numPartitions, File file, TempShuffleBlockId blockId) {
+    this.partitionLengths = new long[numPartitions];
+    this.file = file;
+    this.blockId = blockId;
+  }
+}