update: add extra padding and end message

build.gradle.kts

@@ -7,7 +7,7 @@ plugins {
 }
 
 group = "io.github.gc-garcol"
-version = "1.2.1"
+version = "1.3.0"
 
 java {
     withJavadocJar()

lib-benchmark/src/main/java/gc/garcol/libbenchmark/Pipeline1P3C_OneToManyRingBufferBechmark.java

@@ -14,13 +14,13 @@
 @State(Scope.Thread)
 @BenchmarkMode({ Mode.Throughput, Mode.AverageTime })
 @OutputTimeUnit(TimeUnit.MILLISECONDS)
-@Measurement(iterations = 3, time = 3)
 @Fork(1)
 public class Pipeline1P3C_OneToManyRingBufferBechmark
 {
     @Benchmark
-    @Timeout(time = 20)
-    @Warmup(iterations = 3, time = 20)
+    @Timeout(time = 60)
+    @Measurement(iterations = 1, time = 60)
+    @Warmup(iterations = 1, time = 10)
     public void publish(Pipeline1P3C_OneToManyRingBufferPlan ringBufferPlan, Blackhole blackhole) throws IOException
     {
         ringBufferPlan.writeBuffer.clear();

lib-benchmark/src/main/java/gc/garcol/libbenchmark/Pipeline1P3C_OneToManyRingBufferPlan.java

@@ -29,7 +29,7 @@ public class Pipeline1P3C_OneToManyRingBufferPlan
     @Setup(Level.Trial)
     public void setUp(Blackhole blackhole) throws InterruptedException
     {
-        ringBuffer = new OneToManyRingBuffer(16, 3);
+        ringBuffer = new OneToManyRingBuffer(18, 3);
 
         messageHandler = new MessageHandler()
         {

lib-benchmark/src/main/java/gc/garcol/libbenchmark/Unicast1P1C_OneToManyRingBufferBechmark.java

@@ -14,13 +14,13 @@
 @State(Scope.Thread)
 @BenchmarkMode({ Mode.Throughput, Mode.AverageTime })
 @OutputTimeUnit(TimeUnit.MILLISECONDS)
-@Measurement(iterations = 3, time = 3)
 @Fork(1)
 public class Unicast1P1C_OneToManyRingBufferBechmark
 {
     @Benchmark
-    @Timeout(time = 20)
-    @Warmup(iterations = 2, time = 20)
+    @Timeout(time = 60)
+    @Measurement(iterations = 1, time = 60)
+    @Warmup(iterations = 1, time = 10)
     public void publish(Unicast1P1C_OneToManyRingBufferPlan ringBufferPlan, Blackhole blackhole) throws IOException
     {
         ringBufferPlan.writeBuffer.clear();

lib-benchmark/src/main/java/gc/garcol/libbenchmark/Unicast1P1C_OneToManyRingBufferPlan.java

@@ -29,7 +29,7 @@ public class Unicast1P1C_OneToManyRingBufferPlan
     @Setup(Level.Trial)
     public void setUp(Blackhole blackhole) throws InterruptedException
     {
-        ringBuffer = new OneToManyRingBuffer(16, 1);
+        ringBuffer = new OneToManyRingBuffer(18, 1);
 
         messageHandler = new MessageHandler()
         {

lib-core/build.gradle.kts

@@ -4,7 +4,7 @@ plugins {
 }
 
 group = "io.github.gc-garcol"
-version = "1.2.1"
+version = "1.3.0"
 
 java {
     toolchain {

lib-core/src/main/java/gc/garcol/libcore/OneToManyRingBuffer.java

@@ -24,8 +24,9 @@ public class OneToManyRingBuffer
     private final UnsafeBuffer pointers;
 
     private final int capacity;
-    private final int maxMsgLength;
+    private final int maxRecordLength;
     private final int lastConsumerIndex;
+    private final int consumerSize;
 
     private final int producerPointerIndex;
     private final int[] consumerPointerIndexes;
@@ -36,6 +37,8 @@ public class OneToManyRingBuffer
      */
     public static final int HEADER_LENGTH = Integer.BYTES * 2; // length, type
 
+    public static final int EXTRA_PADDING_LENGTH = Long.BYTES * 8;
+
     /**
      * Alignment as a multiple of bytes for each record.
      * Padding to align the record in order to prevent false sharing.
@@ -61,14 +64,15 @@ public OneToManyRingBuffer(int powSize, int consumerSize)
 
         producerPointerIndex = Long.BYTES * 8;
         consumerPointerIndexes = new int[consumerSize];
+        this.consumerSize = consumerSize;
 
         consumerPointerIndexes[0] = Long.BYTES * 8 + Long.BYTES + Long.BYTES * 7; // padding + producer-pointer-block + padding
         for (int i = 1; i < consumerSize; i++)
         {
             consumerPointerIndexes[i] = consumerPointerIndexes[i - 1] + Long.BYTES + Long.BYTES * 7; // padding + consumer-pointer-block + padding
         }
 
-        maxMsgLength = capacity >> 3;
+        maxRecordLength = capacity >> 3;
     }
 
     /**
@@ -80,13 +84,15 @@ public OneToManyRingBuffer(int powSize, int consumerSize)
      */
     public boolean write(int msgTypeId, ByteBuffer message)
     {
-        int msgLength = message.limit();
-        checkMsgLength(msgLength, maxMsgLength);
+        int messageLength = message.limit();
+        final int recordLength = calculateRecordLength(messageLength);
+        final int alignedRecordLength = BitUtil.align(recordLength, ALIGNMENT);
+        checkMsgLength(alignedRecordLength, maxRecordLength);
 
         // [1] happen-before guarantee for reads
         long currentProducerPosition = pointers.getLongVolatile(producerPointerIndex);
         long firstConsumerPosition = pointers.getLongVolatile(consumerPointerIndexes[0]);
-        long lastConsumerPosition = pointers.getLongVolatile(consumerPointerIndexes[lastConsumerIndex]);
+        long lastConsumerPosition = consumerSize == 1 ? firstConsumerPosition : pointers.getLongVolatile(consumerPointerIndexes[lastConsumerIndex]);
 
         int currentProducerOffset = offset(currentProducerPosition);
         boolean currentProducerFlip = flip(currentProducerPosition);
@@ -95,9 +101,6 @@ public boolean write(int msgTypeId, ByteBuffer message)
         int lastConsumerOffset = offset(lastConsumerPosition);
         boolean lastConsumerFlip = flip(lastConsumerPosition);
 
-        final int recordLength = msgLength + HEADER_LENGTH;
-        final int alignedRecordLength = BitUtil.align(recordLength, ALIGNMENT);
-
         final int expectedEndOffsetOfRecord = currentProducerOffset + alignedRecordLength - 1;
 
         boolean sameCircleWithFirstConsumer = sameCircle(currentProducerFlip, firstConsumerFlip);
@@ -151,8 +154,8 @@ else if (!sameCircleWithLastConsumer) // !sameCircleWithFirstConsumer, the produ
         int nextProducerOffset = (realStartOfRecord + alignedRecordLength) % capacity; // maybe nextProducerOffset == 0
 
         // when [2] happened, the [2] ensures that the these instructions are synchronized into main memory as well
-        buffer.putBytes(realStartOfRecord + HEADER_LENGTH, message, 0, msgLength);
-        buffer.putInt(realStartOfRecord, msgLength);
+        buffer.putBytes(realStartOfRecord + HEADER_LENGTH, message, 0, messageLength);
+        buffer.putInt(realStartOfRecord, messageLength);
         buffer.putInt(realStartOfRecord + Integer.BYTES, msgTypeId);
 
         shouldFlip |= nextProducerOffset == 0;
@@ -284,7 +287,7 @@ public boolean readOne(int consumerIndex, final MessageHandler handler)
             return false;
         }
 
-        int recordLength = messageLength + HEADER_LENGTH;
+        int recordLength = calculateRecordLength(messageLength);
         int alignedRecordLength = BitUtil.align(recordLength, ALIGNMENT);
         int endRecordOffset = currentConsumerOffset + alignedRecordLength - 1;
 
@@ -305,4 +308,9 @@ public boolean readOne(int consumerIndex, final MessageHandler handler)
 
         return true;
     }
+
+    private int calculateRecordLength(int messageLength)
+    {
+        return messageLength + HEADER_LENGTH + EXTRA_PADDING_LENGTH;
+    }
 }

lib-core/src/test/java/gc/garcol/libcore/OneToManyRingBufferTest.java

@@ -141,12 +141,15 @@ public void shouldConsumeThreadSafe_1P2C_10()
 
         oneToManyRingBuffer = new OneToManyRingBuffer(10, 2);
 
+        int publishedMessage = 0;
         for (int i = 0; i < messages.size(); i++)
         {
             messageBufferWriter.clear();
             ByteBufferUtil.put(messageBufferWriter, 0, messages.get(i).getBytes());
             messageBufferWriter.flip();
-            oneToManyRingBuffer.write(i, messageBufferWriter);
+            if (oneToManyRingBuffer.write(i, messageBufferWriter)) {
+                publishedMessage++;
+            }
         }
 
         Function<Integer, MessageHandler> handlerSupplier = (Integer consumerId) ->
@@ -180,7 +183,8 @@ public void shouldConsumeThreadSafe_1P2C_10()
             for (int i = 0; i < messages.size(); i++)
             {
                 UncheckUtil.run(() -> Thread.sleep(15));
-                oneToManyRingBuffer.read(0, handlerSupplier.apply(0), 1);
+                int consumedMessage = oneToManyRingBuffer.read(0, handlerSupplier.apply(0), 1);
+                System.out.println("Consumer 0 consume message: " + consumedMessage);
             }
             end.set(true);
         });
@@ -197,8 +201,8 @@ public void shouldConsumeThreadSafe_1P2C_10()
         UncheckUtil.run(thread0::join);
         UncheckUtil.run(thread1::join);
 
-        Assertions.assertEquals(messages.size(), consumedIndexes.get(0).get(), "Consumer 0 not consume all messages");
-        Assertions.assertEquals(messages.size(), consumedIndexes.get(1).get(), "Consumer 1 not consume all messages");
+        Assertions.assertEquals(publishedMessage, consumedIndexes.get(0).get(), "Consumer 0 not consume all messages");
+        Assertions.assertEquals(publishedMessage, consumedIndexes.get(1).get(), "Consumer 1 not consume all messages");
     }
 
     @Test