ARROW-8481: [Java] Provide an allocation manager based on Unsafe API

java/memory/src/main/java/org/apache/arrow/memory/BaseAllocator.java

@@ -763,7 +763,7 @@ abstract static class Config {
      */
     @Value.Default
     AllocationManager.Factory getAllocationManagerFactory() {
-      return NettyAllocationManager.FACTORY;
+      return DefaultAllocationManagerOption.DEFAULT_ALLOCATION_MANAGER_FACTORY;
     }
 
     /**

java/memory/src/main/java/org/apache/arrow/memory/DefaultAllocationManagerOption.java

@@ -0,0 +1,98 @@
+/*
+ * 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.arrow.memory;
+
+/**
+ * A class for choosing the default allocation manager.
+ */
+public class DefaultAllocationManagerOption {
+
+  /**
+   * The environmental variable to set the default allocation manager type.
+   */
+  public static final String ALLOCATION_MANAGER_TYPE_ENV_NAME = "ARROW_ALLOCATION_MANAGER_TYPE";
+
+  /**
+   * The system property to set the default allocation manager type.
+   */
+  public static final String ALLOCATION_MANAGER_TYPE_PROPERTY_NAME = "arrow.allocation.manager.type";
+
+  static final org.slf4j.Logger LOGGER = org.slf4j.LoggerFactory.getLogger(DefaultAllocationManagerOption.class);
+
+  /**
+   * The default allocation manager factory.
+   */
+  public static final AllocationManager.Factory DEFAULT_ALLOCATION_MANAGER_FACTORY =
+      getDefaultAllocationManagerFactory();
+
+  /**
+   * The allocation manager type.
+   */
+  public enum AllocationManagerType {
+    /**
+     * Netty based allocation manager.
+     */
+    Netty,
+
+    /**
+     * Unsafe based allocation manager.
+     */
+    Unsafe,
+
+    /**
+     * Unknown type.
+     */
+    Unknown,
+  }
+
+  static AllocationManagerType getDefaultAllocationManagerType() {
+    AllocationManagerType ret = AllocationManagerType.Unknown;
+
+    try {
+      String envValue = System.getenv(ALLOCATION_MANAGER_TYPE_ENV_NAME);
+      ret = AllocationManagerType.valueOf(envValue);
+    } catch (IllegalArgumentException | NullPointerException e) {
+      // ignore the exception, and make the allocation manager type remain unchanged
+    }
+
+    // system property takes precedence
+    try {
+      String propValue = System.getProperty(ALLOCATION_MANAGER_TYPE_PROPERTY_NAME);
+      ret = AllocationManagerType.valueOf(propValue);
+    } catch (IllegalArgumentException | NullPointerException e) {
+      // ignore the exception, and make the allocation manager type remain unchanged
+    }
+    return ret;
+  }
+
+  static AllocationManager.Factory getDefaultAllocationManagerFactory() {
+    AllocationManagerType type = getDefaultAllocationManagerType();
+
+    switch (type) {
+      case Netty:
+        return NettyAllocationManager.FACTORY;
+      case Unsafe:
+        return UnsafeAllocationManager.FACTORY;
+      case Unknown:
+        LOGGER.info("allocation manager type not specified, using netty as the default type");
+        return NettyAllocationManager.FACTORY;
+      default:
+        throw new IllegalStateException("Unknown allocation manager type: " + type);
+    }
+  }
+}

java/memory/src/main/java/org/apache/arrow/memory/UnsafeAllocationManager.java

@@ -0,0 +1,65 @@
+/*
+ * 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.arrow.memory;
+
+import org.apache.arrow.memory.util.MemoryUtil;
+
+/**
+ * Allocation manager based on unsafe API.
+ */
+public final class UnsafeAllocationManager extends AllocationManager {
+
+  public static final Factory FACTORY = new Factory();
+
+  private final long allocatedSize;
+
+  private final long allocatedAddress;
+
+  UnsafeAllocationManager(BaseAllocator accountingAllocator, long requestedSize) {
+    super(accountingAllocator);
+    allocatedAddress = MemoryUtil.UNSAFE.allocateMemory(requestedSize);
+    allocatedSize = requestedSize;
+  }
+
+  @Override
+  public long getSize() {
+    return allocatedSize;
+  }
+
+  @Override
+  protected long memoryAddress() {
+    return allocatedAddress;
+  }
+
+  @Override
+  protected void release0() {
+    MemoryUtil.UNSAFE.freeMemory(allocatedAddress);
+  }
+
+  /**
+   * Factory for creating {@link UnsafeAllocationManager}.
+   */
+  public static class Factory implements AllocationManager.Factory {
+    private Factory() {}
+
+    @Override
+    public AllocationManager create(BaseAllocator accountingAllocator, long size) {
+      return new UnsafeAllocationManager(accountingAllocator, size);
+    }
+  }
+}

java/memory/src/test/java/org/apache/arrow/memory/TestAllocationManager.java

@@ -0,0 +1,52 @@
+/*
+ * 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.arrow.memory;
+
+import static org.junit.Assert.assertEquals;
+
+import org.junit.Test;
+
+/**
+ * Test cases for {@link AllocationManager}.
+ */
+public class TestAllocationManager {
+
+  @Test
+  public void testAllocationManagerType() {
+    // test netty allocation manager type
+    System.setProperty(
+        DefaultAllocationManagerOption.ALLOCATION_MANAGER_TYPE_PROPERTY_NAME, "Netty");
+    DefaultAllocationManagerOption.AllocationManagerType mgrType =
+        DefaultAllocationManagerOption.getDefaultAllocationManagerType();
+
+    assertEquals(DefaultAllocationManagerOption.AllocationManagerType.Netty, mgrType);
+
+    // test unsafe allocation manager type
+    System.setProperty(
+        DefaultAllocationManagerOption.ALLOCATION_MANAGER_TYPE_PROPERTY_NAME, "Unsafe");
+    mgrType = DefaultAllocationManagerOption.getDefaultAllocationManagerType();
+
+    assertEquals(DefaultAllocationManagerOption.AllocationManagerType.Unsafe, mgrType);
+
+    // test unknown allocation manager type
+    System.clearProperty(DefaultAllocationManagerOption.ALLOCATION_MANAGER_TYPE_PROPERTY_NAME);
+    mgrType = DefaultAllocationManagerOption.getDefaultAllocationManagerType();
+
+    assertEquals(DefaultAllocationManagerOption.AllocationManagerType.Unknown, mgrType);
+  }
+}

java/memory/src/test/java/org/apache/arrow/memory/TestUnsafeAllocationManager.java

@@ -0,0 +1,70 @@
+/*
+ * 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.arrow.memory;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+import org.junit.Test;
+
+/**
+ * Test cases for {@link UnsafeAllocationManager}.
+ */
+public class TestUnsafeAllocationManager {
+
+  private BaseAllocator createUnsafeAllocator() {
+    return new RootAllocator(BaseAllocator.configBuilder()
+        .allocationManagerFactory((accountingAllocator, requestedSize) ->
+            new UnsafeAllocationManager(
+                accountingAllocator, requestedSize)).build());
+  }
+
+  private void readWriteArrowBuf(ArrowBuf buffer) {
+    // write buffer
+    for (long i = 0; i < buffer.capacity() / 8; i++) {
+      buffer.setLong(i * 8, i);
+    }
+
+    // read buffer
+    for (long i = 0; i < buffer.capacity() / 8; i++) {
+      long val = buffer.getLong(i * 8);
+      assertEquals(i, val);
+    }
+  }
+
+  /**
+   * Test the memory allocation for {@link UnsafeAllocationManager}.
+   */
+  @Test
+  public void testBufferAllocation() {
+    final long bufSize = 4096L;
+    try (BaseAllocator allocator = createUnsafeAllocator();
+         ArrowBuf buffer = allocator.buffer(bufSize)) {
+      assertTrue(buffer.getReferenceManager() instanceof BufferLedger);
+      BufferLedger bufferLedger = (BufferLedger) buffer.getReferenceManager();
+
+      // make sure we are using unsafe allocation manager
+      AllocationManager allocMgr = bufferLedger.getAllocationManager();
+      assertTrue(allocMgr instanceof UnsafeAllocationManager);
+      UnsafeAllocationManager unsafeMgr = (UnsafeAllocationManager) allocMgr;
+
+      assertEquals(bufSize, unsafeMgr.getSize());
+      readWriteArrowBuf(buffer);
+    }
+  }
+}