[SPARK-4664][Core] Throw an exception when spark.akka.frameSize > 2047

If `spark.akka.frameSize` > 2047, it will overflow and become negative. Should have some assertion in `maxFrameSizeBytes` to warn people.

Author: zsxwing <[email protected]>

Closes #3527 from zsxwing/SPARK-4664 and squashes the following commits:

0089c7a [zsxwing] Throw an exception when spark.akka.frameSize > 2047

Author: zsxwing

core/src/main/scala/org/apache/spark/util/AkkaUtils.scala

@@ -134,9 +134,16 @@ private[spark] object AkkaUtils extends Logging {
     Duration.create(conf.getLong("spark.akka.lookupTimeout", 30), "seconds")
   }
 
+  private val AKKA_MAX_FRAME_SIZE_IN_MB = Int.MaxValue / 1024 / 1024
+
   /** Returns the configured max frame size for Akka messages in bytes. */
   def maxFrameSizeBytes(conf: SparkConf): Int = {
-    conf.getInt("spark.akka.frameSize", 10) * 1024 * 1024
+    val frameSizeInMB = conf.getInt("spark.akka.frameSize", 10)
+    if (frameSizeInMB > AKKA_MAX_FRAME_SIZE_IN_MB) {
+      throw new IllegalArgumentException("spark.akka.frameSize should not be greater than "
+        + AKKA_MAX_FRAME_SIZE_IN_MB + "MB")
+    }
+    frameSizeInMB * 1024 * 1024
   }
 
   /** Space reserved for extra data in an Akka message besides serialized task or task result. */