diff --git a/codec-http2/src/main/java/io/netty/handler/codec/http2/Http2StreamChannelBootstrap.java b/codec-http2/src/main/java/io/netty/handler/codec/http2/Http2StreamChannelBootstrap.java
index 3d966154d2..0d46699459 100644
--- a/codec-http2/src/main/java/io/netty/handler/codec/http2/Http2StreamChannelBootstrap.java
+++ b/codec-http2/src/main/java/io/netty/handler/codec/http2/Http2StreamChannelBootstrap.java
@@ -33,15 +33,19 @@ import io.netty.util.internal.logging.InternalLogger;
 import io.netty.util.internal.logging.InternalLoggerFactory;
 
 import java.nio.channels.ClosedChannelException;
-import java.util.LinkedHashMap;
 import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
 
 @UnstableApi
 public final class Http2StreamChannelBootstrap {
     private static final InternalLogger logger = InternalLoggerFactory.getInstance(Http2StreamChannelBootstrap.class);
+    @SuppressWarnings("unchecked")
+    private static final Map.Entry<ChannelOption<?>, Object>[] EMPTY_OPTION_ARRAY = new Map.Entry[0];
+    @SuppressWarnings("unchecked")
+    private static final Map.Entry<AttributeKey<?>, Object>[] EMPTY_ATTRIBUTE_ARRAY = new Map.Entry[0];
 
-    private final Map<ChannelOption<?>, Object> options = new LinkedHashMap<ChannelOption<?>, Object>();
-    private final Map<AttributeKey<?>, Object> attrs = new LinkedHashMap<AttributeKey<?>, Object>();
+    private final Map<ChannelOption<?>, Object> options = new ConcurrentHashMap<ChannelOption<?>, Object>();
+    private final Map<AttributeKey<?>, Object> attrs = new ConcurrentHashMap<AttributeKey<?>, Object>();
     private final Channel channel;
     private volatile ChannelHandler handler;
 
@@ -62,13 +66,9 @@ public final class Http2StreamChannelBootstrap {
             throw new NullPointerException("option");
         }
         if (value == null) {
-            synchronized (options) {
-                options.remove(option);
-            }
+            options.remove(option);
         } else {
-            synchronized (options) {
-                options.put(option, value);
-            }
+            options.put(option, value);
         }
         return this;
     }
@@ -83,13 +83,9 @@ public final class Http2StreamChannelBootstrap {
             throw new NullPointerException("key");
         }
         if (value == null) {
-            synchronized (attrs) {
-                attrs.remove(key);
-            }
+            attrs.remove(key);
         } else {
-            synchronized (attrs) {
-                attrs.put(key, value);
-            }
+            attrs.put(key, value);
         }
         return this;
     }
@@ -204,36 +200,29 @@ public final class Http2StreamChannelBootstrap {
         });
     }
 
-    @SuppressWarnings("unchecked")
     private void init(Channel channel) {
         ChannelPipeline p = channel.pipeline();
         ChannelHandler handler = this.handler;
         if (handler != null) {
             p.addLast(handler);
         }
-        synchronized (options) {
-            setChannelOptions(channel, options);
-        }
-
-        synchronized (attrs) {
-            for (Map.Entry<AttributeKey<?>, Object> e: attrs.entrySet()) {
-                channel.attr((AttributeKey<Object>) e.getKey()).set(e.getValue());
-            }
-        }
+        setChannelOptions(channel, options.entrySet().toArray(EMPTY_OPTION_ARRAY));
+        setAttributes(channel, attrs.entrySet().toArray(EMPTY_ATTRIBUTE_ARRAY));
     }
 
     private static void setChannelOptions(
-            Channel channel, Map<ChannelOption<?>, Object> options) {
-        for (Map.Entry<ChannelOption<?>, Object> e: options.entrySet()) {
+            Channel channel, Map.Entry<ChannelOption<?>, Object>[] options) {
+        for (Map.Entry<ChannelOption<?>, Object> e: options) {
             setChannelOption(channel, e.getKey(), e.getValue());
         }
     }
 
-    @SuppressWarnings("unchecked")
     private static void setChannelOption(
             Channel channel, ChannelOption<?> option, Object value) {
         try {
-            if (!channel.config().setOption((ChannelOption<Object>) option, value)) {
+            @SuppressWarnings("unchecked")
+            ChannelOption<Object> opt = (ChannelOption<Object>) option;
+            if (!channel.config().setOption(opt, value)) {
                 logger.warn("Unknown channel option '{}' for channel '{}'", option, channel);
             }
         } catch (Throwable t) {
@@ -241,4 +230,13 @@ public final class Http2StreamChannelBootstrap {
                     "Failed to set channel option '{}' with value '{}' for channel '{}'", option, value, channel, t);
         }
     }
+
+    private static void setAttributes(
+            Channel channel, Map.Entry<AttributeKey<?>, Object>[] options) {
+        for (Map.Entry<AttributeKey<?>, Object> e: options) {
+            @SuppressWarnings("unchecked")
+            AttributeKey<Object> key = (AttributeKey<Object>) e.getKey();
+            channel.attr(key).set(e.getValue());
+        }
+    }
 }
diff --git a/transport/src/main/java/io/netty/bootstrap/AbstractBootstrap.java b/transport/src/main/java/io/netty/bootstrap/AbstractBootstrap.java
index ab35f06504..50b929a3f7 100644
--- a/transport/src/main/java/io/netty/bootstrap/AbstractBootstrap.java
+++ b/transport/src/main/java/io/netty/bootstrap/AbstractBootstrap.java
@@ -50,6 +50,10 @@ import java.util.concurrent.ConcurrentHashMap;
  * transports such as datagram (UDP).</p>
  */
 public abstract class AbstractBootstrap<B extends AbstractBootstrap<B, C>, C extends Channel> implements Cloneable {
+    @SuppressWarnings("unchecked")
+    static final Map.Entry<ChannelOption<?>, Object>[] EMPTY_OPTION_ARRAY = new Map.Entry[0];
+    @SuppressWarnings("unchecked")
+    static final Map.Entry<AttributeKey<?>, Object>[] EMPTY_ATTRIBUTE_ARRAY = new Map.Entry[0];
 
     volatile EventLoopGroup group;
     @SuppressWarnings("deprecation")
@@ -424,16 +428,6 @@ public abstract class AbstractBootstrap<B extends AbstractBootstrap<B, C>, C ext
         }
     }
 
-    @SuppressWarnings("unchecked")
-    static Map.Entry<AttributeKey<?>, Object>[] newAttrArray(int size) {
-        return new Map.Entry[size];
-    }
-
-    @SuppressWarnings("unchecked")
-    static Map.Entry<ChannelOption<?>, Object>[] newOptionArray(int size) {
-        return new Map.Entry[size];
-    }
-
     @SuppressWarnings("unchecked")
     private static void setChannelOption(
             Channel channel, ChannelOption<?> option, Object value, InternalLogger logger) {
diff --git a/transport/src/main/java/io/netty/bootstrap/Bootstrap.java b/transport/src/main/java/io/netty/bootstrap/Bootstrap.java
index 7e3f478ae8..3822b43b0f 100644
--- a/transport/src/main/java/io/netty/bootstrap/Bootstrap.java
+++ b/transport/src/main/java/io/netty/bootstrap/Bootstrap.java
@@ -35,8 +35,6 @@ import io.netty.util.internal.logging.InternalLoggerFactory;
 import java.net.InetAddress;
 import java.net.InetSocketAddress;
 import java.net.SocketAddress;
-import java.util.Map;
-import java.util.Map.Entry;
 
 /**
  * A {@link Bootstrap} that makes it easy to bootstrap a {@link Channel} to use
@@ -258,8 +256,8 @@ public class Bootstrap extends AbstractBootstrap<Bootstrap, Channel> {
         ChannelPipeline p = channel.pipeline();
         p.addLast(config.handler());
 
-        setChannelOptions(channel, options0().entrySet().toArray(newOptionArray(0)), logger);
-        setAttributes(channel, attrs0().entrySet().toArray(newAttrArray(0)));
+        setChannelOptions(channel, options0().entrySet().toArray(EMPTY_OPTION_ARRAY), logger);
+        setAttributes(channel, attrs0().entrySet().toArray(EMPTY_ATTRIBUTE_ARRAY));
     }
 
     @Override
diff --git a/transport/src/main/java/io/netty/bootstrap/ServerBootstrap.java b/transport/src/main/java/io/netty/bootstrap/ServerBootstrap.java
index c0041936e2..a66fc30aa5 100644
--- a/transport/src/main/java/io/netty/bootstrap/ServerBootstrap.java
+++ b/transport/src/main/java/io/netty/bootstrap/ServerBootstrap.java
@@ -123,16 +123,16 @@ public class ServerBootstrap extends AbstractBootstrap<ServerBootstrap, ServerCh
 
     @Override
     void init(Channel channel) {
-        setChannelOptions(channel, options0().entrySet().toArray(newOptionArray(0)), logger);
-        setAttributes(channel, attrs0().entrySet().toArray(newAttrArray(0)));
+        setChannelOptions(channel, options0().entrySet().toArray(EMPTY_OPTION_ARRAY), logger);
+        setAttributes(channel, attrs0().entrySet().toArray(EMPTY_ATTRIBUTE_ARRAY));
 
         ChannelPipeline p = channel.pipeline();
 
         final EventLoopGroup currentChildGroup = childGroup;
         final ChannelHandler currentChildHandler = childHandler;
         final Entry<ChannelOption<?>, Object>[] currentChildOptions =
-                childOptions.entrySet().toArray(newOptionArray(0));
-        final Entry<AttributeKey<?>, Object>[] currentChildAttrs = childAttrs.entrySet().toArray(newAttrArray(0));
+                childOptions.entrySet().toArray(EMPTY_OPTION_ARRAY);
+        final Entry<AttributeKey<?>, Object>[] currentChildAttrs = childAttrs.entrySet().toArray(EMPTY_ATTRIBUTE_ARRAY);
 
         p.addLast(new ChannelInitializer<Channel>() {
             @Override