diff --git a/broker/src/main/java/io/moquette/spi/impl/ProtocolProcessor.java b/broker/src/main/java/io/moquette/spi/impl/ProtocolProcessor.java
index 6320861b..5199b19c 100644
--- a/broker/src/main/java/io/moquette/spi/impl/ProtocolProcessor.java
+++ b/broker/src/main/java/io/moquette/spi/impl/ProtocolProcessor.java
@@ -571,10 +571,12 @@ public class ProtocolProcessor {
         Channel channel = m_clientIDs.get(clientId).channel;
         LOG.trace("Session for clientId {}", clientId);
         if (channel.isWritable()) {
+            LOG.debug("channel is writable");
             //if channel is writable don't enqueue
-            channel.write(pubMessage);
+            channel.writeAndFlush(pubMessage);
         } else {
             //enqueue to the client session
+            LOG.debug("enqueue to client session");
             clientsession.enqueue(pubMessage);
         }
     }
diff --git a/tools_scripts/benchmark/conSubPubUnsub_issue204.groovy b/tools_scripts/benchmark/conSubPubUnsub_issue204.groovy
new file mode 100644
index 00000000..fc9f0c45
--- /dev/null
+++ b/tools_scripts/benchmark/conSubPubUnsub_issue204.groovy
@@ -0,0 +1,115 @@
+@GrabResolver(name='Paho', root='https://repo.eclipse.org/content/repositories/paho-releases/')
+@Grab(group='org.eclipse.paho', module='mqtt-client', version='0.4.0')
+@Grab(group='org.eclipse.jetty.toolchain', module='jetty-perf-helper', version='1.0.5')
+
+import org.eclipse.paho.client.mqttv3.MqttAsyncClient
+import org.eclipse.paho.client.mqttv3.MqttMessage
+import org.eclipse.paho.client.mqttv3.MqttException
+import org.eclipse.paho.client.mqttv3.MqttCallback
+import org.eclipse.paho.client.mqttv3.IMqttDeliveryToken
+import org.eclipse.paho.client.mqttv3.persist.MqttDefaultFilePersistence
+import org.HdrHistogram.Histogram
+import org.eclipse.jetty.toolchain.perf.PlatformTimer
+
+import java.nio.ByteBuffer
+import java.util.concurrent.Semaphore
+
+/**
+ * Performance metric test for issue 204.
+ * One topic per client
+ * Flow:
+ * [MEASURE START]
+ * - connect
+ * - subscribe to topic "test"+i
+ * - publish something on "test"+i
+ * - unsubscribe from "test"+i
+ * - disconnect
+ * [MEASURE STOP]
+ * */
+
+class WorkflowTask implements MqttCallback {
+    private MqttAsyncClient client
+    private int clientCounter
+    private long startTime
+    private long numOfIterations
+    Histogram histogram
+    private int pauseMicroseconds
+    private PlatformTimer timer = PlatformTimer.detect()
+    private Semaphore disconnectReceived = new Semaphore(0)
+
+    void execute() {
+        client.callback = this
+
+        (1..numOfIterations).each { it ->
+            startTime = System.nanoTime()
+            client.connect().waitForCompletion(1000)
+            println "connected ${it}"
+            client.subscribe("/topic${clientCounter}", 0)
+            println "subscribed to /topic${clientCounter}"
+            //byte[] bytes = ByteBuffer.allocate(8).putLong(System.currentTimeMillis()).array()
+            byte[] bytes = "TestPayload".bytes
+            client.publish("/topic${clientCounter}", bytes, 0, false)
+            println "published to /topic${clientCounter}..wait for receive of message"
+
+            disconnectReceived.acquire()
+            println "Acquired semaphore, value ${disconnectReceived.availablePermits()}"
+            client.disconnect().waitForCompletion(1000)
+            println "Disconnected"
+            long stopTime = System.nanoTime()
+            long spentNanoSeconds = stopTime - startTime
+            histogram.recordValue(spentNanoSeconds)
+
+            //timer.sleep(pauseMicroseconds)
+        }
+        println "Latency diagram (micro secs):\n"
+        histogram.outputPercentileDistribution(System.out, 1000.0)
+    }
+
+    public void messageArrived(String topic, MqttMessage message) throws Exception {
+        println "Received published"
+        if (topic != "/topic${clientCounter}".toString()) {
+            println "Error received a publish on not matching topic ${topic}"
+            return
+        }
+        long stopTime = System.nanoTime()
+        long spentNanoSeconds = stopTime - startTime
+
+        disconnectReceived.release()
+        println "Released semaphore, value ${disconnectReceived.availablePermits()}"
+    }
+
+    public void connectionLost(Throwable cause) {
+//        println "Client ${clientCounter} lost connection"
+    }
+
+    public void deliveryComplete(IMqttDeliveryToken token) {
+
+    }
+
+}
+
+MqttAsyncClient createClient(int i) {
+    String tmpDir = System.getProperty("java.io.tmpdir")
+    MqttDefaultFilePersistence dataStore = new MqttDefaultFilePersistence(tmpDir)
+    new MqttAsyncClient("tcp://localhost:1883", "TestClient${i}", dataStore)
+}
+
+Histogram histogram = new Histogram(5)
+if (args.size() != 2) {
+    println "Usage:"
+    println "\n groovy conSubPubUnsub_issue204.groovy <num of iterations per second> <seconds>"
+    return 1
+}
+int numOfIterationsPerSecond = args[0] as int
+int duration = args[1] as int
+long pauseMicroseconds = (1 / numOfIterationsPerSecond) * 1000 * 1000
+long numOfIterations = numOfIterationsPerSecond * duration
+
+MqttAsyncClient client = createClient(0)
+def task = new WorkflowTask(client: client, clientCounter: 0, histogram: histogram,
+        pauseMicroseconds: pauseMicroseconds, numOfIterations: numOfIterations)
+
+task.execute()
+
+//println "Latency diagram:\n"
+//histogram.outputPercentileDistribution(System.out, 1000.0)
\ No newline at end of file