Merge pull request #5364 from eclipse-vertx/franz1981-4.x_unified_all…

…ocator

Franz1981 4.x unified allocator

pom.xml

@@ -755,6 +755,21 @@
               </additionalClasspathElements>
             </configuration>
           </execution>
+          <execution>
+            <id>reuse-netty-allocators</id>
+            <goals>
+              <goal>integration-test</goal>
+              <goal>verify</goal>
+            </goals>
+            <configuration>
+              <includes>
+                <include>io/vertx/it/ReuseNettyAllocatorsTest.java</include>
+              </includes>
+              <systemProperties>
+                <vertx.reuseNettyAllocators>true</vertx.reuseNettyAllocators>
+              </systemProperties>
+            </configuration>
+          </execution>
         </executions>
       </plugin>
 
@@ -986,4 +1001,4 @@
 
   </profiles>
 
-</project>
+</project>

src/main/java/io/vertx/core/buffer/impl/VertxByteBufAllocator.java

@@ -19,12 +19,15 @@
 
 public abstract class VertxByteBufAllocator extends AbstractByteBufAllocator {
 
+  private static final boolean REUSE_NETTY_ALLOCATOR = Boolean.getBoolean("vertx.reuseNettyAllocators");
+
   /**
-   * Vert.x pooled allocator.
+   * Vert.x pooled allocator. It should prefers direct buffers, unless {@link PlatformDependent#hasUnsafe()} is {@code false}.
    */
-  public static final ByteBufAllocator POOLED_ALLOCATOR = new PooledByteBufAllocator(true);
+  public static final ByteBufAllocator POOLED_ALLOCATOR = (REUSE_NETTY_ALLOCATOR && PooledByteBufAllocator.defaultPreferDirect()) ?
+    PooledByteBufAllocator.DEFAULT : new PooledByteBufAllocator(true);
   /**
-   * Vert.x shared unpooled allocator.
+   * Vert.x shared unpooled allocator. It prefers non-direct buffers.
    */
   public static final ByteBufAllocator UNPOOLED_ALLOCATOR = new UnpooledByteBufAllocator(false);
 
@@ -42,6 +45,10 @@ protected ByteBuf newHeapBuffer(int initialCapacity, int maxCapacity) {
     }
   };
 
+  /**
+   * Vert.x shared unpooled heap buffers allocator.<br>
+   * Differently from {@link #UNPOOLED_ALLOCATOR}, its buffers are not reference-counted and array-backed.
+   */
   public static final VertxByteBufAllocator DEFAULT = PlatformDependent.hasUnsafe() ? UNSAFE_IMPL : IMPL;
 
   @Override

src/test/java/io/vertx/core/buffer/impl/VertxByteBufAllocatorTest.java

@@ -0,0 +1,29 @@
+/*
+ * Copyright (c) 2011-2024 Contributors to the Eclipse Foundation
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0, or the Apache License, Version 2.0
+ * which is available at https://www.apache.org/licenses/LICENSE-2.0.
+ *
+ * SPDX-License-Identifier: EPL-2.0 OR Apache-2.0
+ */
+
+package io.vertx.core.buffer.impl;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+import io.netty.buffer.ByteBufAllocator;
+import io.netty.buffer.PooledByteBufAllocator;
+
+public class VertxByteBufAllocatorTest {
+
+  @Test
+  public void defaultShouldNotReuseExistingNettyPooledAllocators() {
+    Assert.assertNull(System.getProperty("vertx.reuseNettyAllocators"));
+    Assert.assertNotSame(PooledByteBufAllocator.DEFAULT, VertxByteBufAllocator.POOLED_ALLOCATOR);
+    Assert.assertNotSame(ByteBufAllocator.DEFAULT, VertxByteBufAllocator.POOLED_ALLOCATOR);
+    Assert.assertSame(ByteBufAllocator.DEFAULT, PooledByteBufAllocator.DEFAULT);
+  }
+}

src/test/java/io/vertx/it/ReuseNettyAllocatorsTest.java

@@ -0,0 +1,29 @@
+/*
+ * Copyright (c) 2011-2024 Contributors to the Eclipse Foundation
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0, or the Apache License, Version 2.0
+ * which is available at https://www.apache.org/licenses/LICENSE-2.0.
+ *
+ * SPDX-License-Identifier: EPL-2.0 OR Apache-2.0
+ */
+
+package io.vertx.it;
+
+import io.netty.buffer.ByteBufAllocator;
+import io.netty.buffer.PooledByteBufAllocator;
+import io.vertx.core.buffer.impl.VertxByteBufAllocator;
+import org.junit.Assert;
+import org.junit.Test;
+
+public class ReuseNettyAllocatorsTest {
+
+  @Test
+  public void testVertxAllocatorsReuseNettyAllocators() {
+    Assert.assertEquals("true", System.getProperty("vertx.reuseNettyAllocators"));
+    Assert.assertSame(PooledByteBufAllocator.DEFAULT, VertxByteBufAllocator.POOLED_ALLOCATOR);
+    Assert.assertSame(ByteBufAllocator.DEFAULT, VertxByteBufAllocator.POOLED_ALLOCATOR);
+    Assert.assertSame(ByteBufAllocator.DEFAULT, PooledByteBufAllocator.DEFAULT);
+  }
+}