From 4fb536dcd38b21d5844611c03e436edff996006f Mon Sep 17 00:00:00 2001
From: Reynold Xin <rxin@databricks.com>
Date: Thu, 13 Aug 2015 01:27:03 -0700
Subject: [PATCH] [SPARK-9934] Deprecate NIO ConnectionManager.

---
 core/src/main/scala/org/apache/spark/SparkEnv.scala | 2 ++
 docs/configuration.md                               | 3 ++-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/core/src/main/scala/org/apache/spark/SparkEnv.scala b/core/src/main/scala/org/apache/spark/SparkEnv.scala
index a796e72850191..0f1e2e069568d 100644
--- a/core/src/main/scala/org/apache/spark/SparkEnv.scala
+++ b/core/src/main/scala/org/apache/spark/SparkEnv.scala
@@ -331,6 +331,8 @@ object SparkEnv extends Logging {
         case "netty" =>
           new NettyBlockTransferService(conf, securityManager, numUsableCores)
         case "nio" =>
+          logWarning("NIO-based block transfer service is deprecated, " +
+            "and will be removed in Spark 1.6.0.")
           new NioBlockTransferService(conf, securityManager)
       }
 
diff --git a/docs/configuration.md b/docs/configuration.md
index c60dd16839c02..32147098ae64a 100644
--- a/docs/configuration.md
+++ b/docs/configuration.md
@@ -389,7 +389,8 @@ Apart from these, the following properties are also available, and may be useful
     Implementation to use for transferring shuffle and cached blocks between executors. There
     are two implementations available: <code>netty</code> and <code>nio</code>. Netty-based
     block transfer is intended to be simpler but equally efficient and is the default option
-    starting in 1.2.
+    starting in 1.2, and <code>nio</code> block transfer is deprecated in Spark 1.5.0 and will
+    be removed in Spark 1.6.0.
   </td>
 </tr>
 <tr>