diff --git a/common/src/main/java/io/netty/util/internal/PlatformDependent.java b/common/src/main/java/io/netty/util/internal/PlatformDependent.java
index 2450c34a77..c50e7606a9 100644
--- a/common/src/main/java/io/netty/util/internal/PlatformDependent.java
+++ b/common/src/main/java/io/netty/util/internal/PlatformDependent.java
@@ -16,6 +16,8 @@
 package io.netty.util.internal;
 
 import io.netty.util.internal.chmv8.ConcurrentHashMapV8;
+import io.netty.util.internal.logging.InternalLogger;
+import io.netty.util.internal.logging.InternalLoggerFactory;
 
 import java.lang.reflect.Field;
 import java.net.InetSocketAddress;
@@ -56,6 +58,16 @@ public final class PlatformDependent {
 
     private static final boolean HAS_JAVASSIST = hasJavassist0();
 
+    static {
+        InternalLogger logger = InternalLoggerFactory.getInstance(PlatformDependent.class);
+        if (!hasUnsafe()) {
+            logger.warn(
+                    "Your platform does not provide complete low-level API for accessing direct buffers reliably. " +
+                    "Unless explicitly requested, heap buffer will always be preferred " +
+                    "to avoid potential risk of getting OutOfMemoryError.");
+        }
+    }
+
     /**
      * Returns {@code true} if and only if the current platform is Android
      */