diff --git a/src/main/java/biz/paluch/logging/gelf/intern/sender/GelfTCPSender.java b/src/main/java/biz/paluch/logging/gelf/intern/sender/GelfTCPSender.java
index 166b682b3..41b2f1a93 100644
--- a/src/main/java/biz/paluch/logging/gelf/intern/sender/GelfTCPSender.java
+++ b/src/main/java/biz/paluch/logging/gelf/intern/sender/GelfTCPSender.java
@@ -3,6 +3,7 @@
 import java.io.IOException;
 import java.net.ConnectException;
 import java.net.InetSocketAddress;
+import java.net.SocketException;
 import java.nio.ByteBuffer;
 import java.nio.channels.SocketChannel;
 import java.util.concurrent.TimeUnit;
@@ -28,7 +29,7 @@ public class GelfTCPSender extends AbstractNioSender<SocketChannel> implements G
     private final boolean keepAlive;
     private final int deliveryAttempts;
 
-    private final Object connectLock = new Object();
+    private final Object ioLock = new Object();
 
     private final ThreadLocal<ByteBuffer> writeBuffers = new ThreadLocal<ByteBuffer>() {
         @Override
@@ -75,7 +76,7 @@ public GelfTCPSender(String host, int port, int connectTimeoutMs, int readTimeou
         this.setChannel(createSocketChannel(readTimeoutMs, keepAlive));
     }
 
-    private SocketChannel createSocketChannel(int readTimeoutMs, boolean keepAlive) throws IOException {
+    protected SocketChannel createSocketChannel(int readTimeoutMs, boolean keepAlive) throws IOException {
         SocketChannel socketChannel = SocketChannel.open();
         socketChannel.configureBlocking(false);
         socketChannel.socket().setKeepAlive(keepAlive);
@@ -100,15 +101,26 @@ public boolean sendMessage(GelfMessage message) {
 
                 // (re)-connect if necessary
                 if (!isConnected()) {
-                    synchronized (connectLock) {
+                    synchronized (ioLock) {
                         connect();
                     }
                 }
-
+                ByteBuffer buffer;
                 if (BUFFER_SIZE == 0) {
-                    channel().write(message.toTCPBuffer());
+                    buffer = message.toTCPBuffer();
                 } else {
-                    channel().write(message.toTCPBuffer(getByteBuffer()));
+                    buffer = message.toTCPBuffer(getByteBuffer());
+                }
+
+                synchronized (ioLock) {
+                    while (buffer.hasRemaining()) {
+                        int written = channel().write(buffer);
+                        if (written < 0) {
+                            // indicator the socket was closed
+                            Closer.close(channel());
+                            throw new SocketException("Cannot write buffer to channel");
+                        }
+                    }
                 }
 
                 return true;
diff --git a/src/main/java/biz/paluch/logging/gelf/intern/sender/GelfUDPSender.java b/src/main/java/biz/paluch/logging/gelf/intern/sender/GelfUDPSender.java
index 889cea07a..69dfb59cd 100644
--- a/src/main/java/biz/paluch/logging/gelf/intern/sender/GelfUDPSender.java
+++ b/src/main/java/biz/paluch/logging/gelf/intern/sender/GelfUDPSender.java
@@ -17,7 +17,7 @@
  */
 public class GelfUDPSender extends AbstractNioSender<DatagramChannel> implements GelfSender {
 
-    private final Object connectLock = new Object();
+    private final Object ioLock = new Object();
 
     private final ThreadLocal<ByteBuffer> writeBuffers = new ThreadLocal<ByteBuffer>() {
         @Override
@@ -60,13 +60,18 @@ private boolean sendDatagrams(ByteBuffer[] bytesList) {
         try {
             // (re)-connect if necessary
             if (!isConnected()) {
-                synchronized (connectLock) {
+                synchronized (ioLock) {
                     connect();
                 }
             }
 
             for (ByteBuffer buffer : bytesList) {
-                channel().write(buffer);
+
+                synchronized (ioLock) {
+                    while (buffer.hasRemaining()) {
+                        channel().write(buffer);
+                    }
+                }
             }
         } catch (IOException e) {
             reportError(e.getMessage(), new IOException("Cannot send data to " + getHost() + ":" + getPort(), e));
@@ -99,7 +104,6 @@ protected void connect() throws IOException {
         } catch (SocketException e) {
             reportError(e.getMessage(), e);
         }
-
     }
 
     @Override
diff --git a/src/test/java/biz/paluch/logging/gelf/intern/sender/GelfTCPSenderIntegrationTest.java b/src/test/java/biz/paluch/logging/gelf/intern/sender/GelfTCPSenderIntegrationTest.java
new file mode 100644
index 000000000..77a06f4ae
--- /dev/null
+++ b/src/test/java/biz/paluch/logging/gelf/intern/sender/GelfTCPSenderIntegrationTest.java
@@ -0,0 +1,104 @@
+package biz.paluch.logging.gelf.intern.sender;
+
+import static org.fest.assertions.Assertions.assertThat;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.ServerSocket;
+import java.net.Socket;
+import java.nio.ByteBuffer;
+import java.nio.channels.SocketChannel;
+import java.util.concurrent.CountDownLatch;
+
+import org.apache.commons.io.IOUtils;
+import org.apache.commons.lang.StringUtils;
+import org.junit.Test;
+
+import biz.paluch.logging.gelf.intern.ErrorReporter;
+import biz.paluch.logging.gelf.intern.GelfMessage;
+
+/**
+ * @author <a href="mailto:mpaluch@paluch.biz">Mark Paluch</a>
+ */
+public class GelfTCPSenderIntegrationTest {
+
+    private ByteArrayOutputStream out = new ByteArrayOutputStream();
+
+    @Test(timeout = 10000)
+    public void name() throws Exception {
+
+        final ServerSocket serverSocket = new ServerSocket(1234);
+        final CountDownLatch latch = new CountDownLatch(1);
+        serverSocket.setSoTimeout(1000);
+
+        Thread thread = new Thread("GelfTCPSenderIntegrationTest-server") {
+
+            @Override
+            public void run() {
+
+                try {
+                    Socket socket = serverSocket.accept();
+                    socket.setKeepAlive(true);
+                    InputStream inputStream = socket.getInputStream();
+
+                    while (!socket.isClosed()) {
+                        IOUtils.copy(inputStream, out);
+                        Thread.sleep(1);
+
+                        if (latch.getCount() == 0) {
+                            socket.close();
+                        }
+                    }
+
+                } catch (IOException e) {
+                    e.printStackTrace();
+                } catch (InterruptedException e) {
+                }
+            }
+        };
+
+        try {
+            thread.start();
+
+            SmallBufferTCPSender sender = new SmallBufferTCPSender("localhost", 1234, 1000, 1000, new ErrorReporter() {
+                @Override
+                public void reportError(String message, Exception e) {
+                }
+            });
+
+            GelfMessage gelfMessage = new GelfMessage("hello", StringUtils.repeat("hello", 100000), 1234, "7");
+            ByteBuffer byteBuffer = gelfMessage.toTCPBuffer();
+            int size = byteBuffer.remaining();
+
+            sender.sendMessage(gelfMessage);
+            sender.close();
+
+            latch.countDown();
+            thread.join();
+
+            assertThat(out.size()).isEqualTo(size);
+
+        } finally {
+            thread.interrupt();
+        }
+
+    }
+
+    static class SmallBufferTCPSender extends GelfTCPSender {
+
+        public SmallBufferTCPSender(String host, int port, int connectTimeoutMs, int readTimeoutMs, ErrorReporter errorReporter)
+                throws IOException {
+            super(host, port, connectTimeoutMs, readTimeoutMs, errorReporter);
+        }
+
+        @Override
+        protected SocketChannel createSocketChannel(int readTimeoutMs, boolean keepAlive) throws IOException {
+            SocketChannel socketChannel = super.createSocketChannel(readTimeoutMs, keepAlive);
+
+            socketChannel.socket().setSendBufferSize(100);
+
+            return socketChannel;
+        }
+    }
+}